Back contact battery and photovoltaic module

Abstract

The invention discloses a back contact battery and a photovoltaic module, relates to the technical field of photovoltaic, and aims to effectively control the leakage loss of the back contact battery while reducing the reverse breakdown voltage of the back contact battery. The back contact battery comprises a semiconductor substrate, a first doped region, a second doped region and at least one conductive semiconductor structure. Each conductive semiconductor structure is at least partially located between the first doped region and the second doped region, and only a partial region of the first doped region and only a partial region of the second doped region are in electrical contact with at least one conductive semiconductor structure. Each of the first doped region and the second doped region comprises a plurality of strip-shaped doped regions and at least one connecting region. The strip-shaped doped regions included in the first doped region and the second doped region are parallel and alternately distributed on one side of the backlight surface of the semiconductor substrate at intervals. The at least one conductive semiconductor structure is at least partially located between one strip-shaped doped region included in one of the first doped region and the second doped region and an adjacent connection region included in the other one of the first doped region and the second doped region.

Description

[0001] This application is a divisional application of application number 202410175657.5, and the invention title is "A back contact battery and photovoltaic module". The application date of the patent application with application number 202410175657.5 is February 7, 2024. Technical Field

[0002] The present invention relates to the field of photovoltaic technology, and in particular to a back contact cell and a photovoltaic module. Background Art

[0003] Back-contact cells refer to solar cells with no electrodes on the light-facing side of the cell, and both the positive and negative electrodes are arranged on the back-light side of the cell, thereby reducing the shading of the cell by the electrodes, increasing the short-circuit current of the cell, and improving the energy conversion efficiency of the cell. Specifically, in existing back-contact cells, the two doping layers of opposite conductivity types that are co-located on the back-light side of the cell are partially isolated by intermittent spacing areas to reduce the reverse breakdown voltage of the back-contact cell and reduce the risk of hot spots from the component end.

[0004] However, the width of the unbroken portion of the spacing area in the existing back-contact battery along its own extension direction is set unreasonably, resulting in a large leakage current of the back-contact battery from the battery end, thereby making the working efficiency of the back-contact battery poor. Summary of the invention

[0005] The object of the present invention is to provide a back-contact cell and a photovoltaic module, so that a first doping region and a second doping region of opposite conductivity types are locally electrically connected through a conductive semiconductor structure, thereby effectively reducing the reverse breakdown voltage of the back-contact cell, and at the same time reasonably setting the width of each conductive semiconductor structure along the extension direction of the spacing region, effectively controlling the leakage loss of the back-contact cell, thereby making the back-contact cell have a higher working efficiency.

[0006] In order to achieve the above-mentioned object, in the first aspect, the present invention provides a back contact battery, which includes: a semiconductor substrate, a first doping region, a second doping region and at least one conductive semiconductor structure. Each conductive semiconductor structure is at least partially located between the first doping region and the second doping region, and only a part of the first doping region and only a part of the second doping region are respectively electrically in contact with at least one conductive semiconductor structure. The first doping region and the second doping region have opposite conductivity types, and the conductivity type of the conductive semiconductor structure is opposite to the conductivity type of one of the first doping region and the second doping region. Wherein, the first doping region and the second doping region each include a plurality of strip doping regions and at least one connection region; the strip doping regions included in the first doping region and the strip doping regions included in the second doping region are parallel and alternately distributed on one side of the backlight surface of the semiconductor substrate; each connection region is electrically connected to a corresponding strip doping region of the same conductivity type as itself; and the extension direction of the connection region is different from the extension direction of the strip doping region. At least a portion of the at least one conductive semiconductor structure is located between a strip doping region included in one of the first doping region and the second doping region and an adjacent connection region included in the other.

[0007] In the case of adopting the above technical solution, the first doping region and the second doping region of opposite conductivity types are distributed on the backlight side of the semiconductor substrate to effectively shunt carriers when the back contact battery is in a working state, which is conducive to the formation of photocurrent. Secondly, the back contact battery provided by the present invention also includes at least one conductive semiconductor structure at least partially located between the first doping region and the second doping region. Based on this, since each conductive semiconductor structure has conductive properties, and the conductive type of the conductive semiconductor structure is opposite to the conductive type of one of the first doping region and the second doping region, when the conductive semiconductor structure is electrically in contact with a partial area of ​​the first doping region and a partial area of ​​the second doping region respectively, the first doping region and the second doping region can be electrically connected by manufacturing a local leakage point to form a built-in diode with a lower reverse breakdown voltage, which is conducive to making the back contact battery have a lower reverse breakdown voltage when it is blocked.

[0008] In addition, only part of the first doping region and only part of the second doping region are respectively in electrical contact with the at least one conductive semiconductor structure. In other words, part of the first doping region and the corresponding part of the second doping region are respectively in electrical contact with the at least one conductive semiconductor structure, while the remaining areas of the first doping region and the corresponding areas of the second doping region are still physically isolated by insulating grooves or insulating materials, etc., to prevent the leakage current of the back contact battery under normal working conditions from being large due to the conductive semiconductor structure being arranged between all the areas of the first doping region and the second doping region, resulting in low working efficiency of the back contact battery, and to ensure that the photovoltaic module including the back contact battery provided by the present invention has a high photoelectric conversion efficiency in the forward voltage region. At least part of the at least one conductive semiconductor structure is located between a strip-shaped doping region included in one of the first doping region and the second doping region and an adjacent connection region included in the other, so as to facilitate the regulation of the reverse breakdown voltage and forward leakage loss of the back contact battery by adjusting the size of the conductive semiconductor structure according to the actual application scenario, thereby improving the working performance of the back contact battery provided by the present invention.

[0009] As a possible implementation scheme, the area between the first doping region and the second doping region is a spacing region. The conductive semiconductor structure includes a first conductive semiconductor portion and a second conductive semiconductor portion that are in electrical contact. The first conductive semiconductor portion is located in the spacing region, and the second conductive semiconductor portion is arranged above a portion of the first doping region and / or the second doping region that is away from the semiconductor substrate. Among them, in the first doping region, the width of the strip doping region corresponding to the conductive semiconductor structure is D2. In the second doping region, the width of the strip doping region corresponding to the conductive semiconductor structure is D3.

[0010] When the above technical solution is adopted, it is possible to avoid strictly requiring etching accuracy in order to obtain only a conductive semiconductor structure located only between the first doping region and the second doping region, thereby reducing the difficulty of etching. At the same time, it can also ensure that the first doping region can be partially electrically connected through the conductive semiconductor structure.

[0011] As a possible implementation scheme, in the second conductive semiconductor portion, the width of the portion disposed above the strip doping region included in the first doping region and / or the strip doping region included in the second doping region along the width direction of the strip doping region is X1. Along the extension direction of the spacing region, the width of the conductive semiconductor structure is W; when the corresponding configuration of the second conductive semiconductor portion is an electrical configuration, X1≤W≤40X1, and / or, the effective electrical contact height of the side surface where the first doping region and the second doping region are electrically connected through the conductive semiconductor structure is Z, and one thousand five hundredth of X1≤Z≤one four hundredth of X1.

[0012] In the case of adopting the above technical solution, when the setting mode corresponding to the second conductive semiconductor part is an electrical setting, the effective electrical contact area between the conductive semiconductor structure and the first doping region and the second doping region respectively includes not only the contact area between the side wall of the conductive semiconductor structure and the first doping region or the second doping region, but also includes the contact area between the second conductive semiconductor part and the corresponding strip-shaped doping region. Based on this, the size of the above effective electrical contact area can be adjusted by adjusting the numerical value of at least one of X1, W and Z, thereby affecting the reverse breakdown voltage corresponding to the back contact battery and the size of the leakage current under normal working conditions. In this case, when X1≤W≤40X1, the width W of the conductive semiconductor structure has a large optional range, and the reverse breakdown voltage corresponding to the back contact battery and the leakage current under normal working conditions can be adjusted by adjusting the width W of the conductive semiconductor structure, which is beneficial to improve the applicability of the back contact battery provided by the present invention in different application scenarios. In addition, when W is within the above range, it can prevent the high manufacturing precision requirements for the conductive semiconductor structure due to the small W, which is conducive to reducing the manufacturing difficulty of the back contact battery; it can also prevent the small W from causing the reverse breakdown voltage corresponding to the back contact battery to be reduced to the working requirements, resulting in a large setting value of X1 and / or Z, thereby affecting the formation quality of the electrode structure, etc., and improving the yield of the back contact battery. At the same time, it can also prevent W from being large, resulting in a large leakage current corresponding to a single conductive semiconductor structure, ensuring that the back contact battery has a high working performance under normal operation. In addition, the beneficial effect of one thousand five hundredth of X1 ≤ Z ≤ one four hundredth of X1 is similar to the beneficial effect of X1 ≤ W ≤ 40X1, which will not be repeated here.

[0013] As a possible implementation scheme, in the second conductive semiconductor portion, the setting width of the portion arranged above the strip doping region included in the first doping region and / or the strip doping region included in the second doping region along the extension direction of the strip doping region is X2; when the second conductive semiconductor portion is arranged above the strip doping region included in the first doping region, 0.1D2≤X2≤1.2D2; and / or, when the second conductive semiconductor portion is arranged above the strip doping region included in the second doping region, 0.1D3≤X2≤1.2D3.

[0014] In the case of adopting the above technical solution, the conductive semiconductor structure is set on the strip doping area included in the first doping area along the extension direction of the strip doping area as an example for explanation: As mentioned above, the carriers collected by the first doping area need to be led out through the electrode structure in ohmic contact with itself. In addition, the extension length of the electrode structure on the strip doping area included in the first doping area will affect the contact resistance between itself and the first doping area, and the carriers collected by each part of the strip doping area included in the first doping area can be timely led out through the electrode structure. Based on this, when 0.1D2≤X2≤1.2D2, it can be prevented that the etching accuracy is strictly required due to the formation of a conductive semiconductor structure with a small setting width due to the small setting width X2 of the second conductive semiconductor part, which is conducive to reducing the manufacturing difficulty of the back contact battery; at the same time, it can also be prevented that when the setting mode corresponding to the second conductive semiconductor part is an electrical setting, the setting width X2 is small, so that the effective electrical contact area corresponding to the conductive semiconductor structure is also small, resulting in poor effect of reducing the risk of hot spots by setting a conductive semiconductor structure in the back contact battery. In addition, it can also prevent the end of the electrode structure along the extension direction of the strip doping region from being too far away from the edge of the strip doping region, which causes the carriers collected at the edge of the strip doping region along the length direction to be unable to be promptly extracted, thereby ensuring that the back contact battery has good working performance. As for the beneficial effects of 0.1D3≤X2≤1.2D3, reference can be made to the beneficial effects analysis of 0.1D2≤X2≤1.2D2, which will not be repeated here.

[0015] As a possible implementation scheme, in the first doping region and the second doping region, the width of the connection region corresponding to the conductive semiconductor structure is W1; in the second conductive semiconductor part, the setting width of the part arranged on the connection region included in the first doping region and / or the connection region included in the second doping region along the extension direction of the strip-shaped doping region is X3; 0.1W1≤X3≤0.3W1.

[0016] In the case of adopting the above technical solution, in the actual application process, the electrode structure will also be formed above the connection area, and may even be in ohmic contact with the connection area. Based on this, the portion of the electrode structure located above the connection area needs to occupy a certain width of the connection area. In this case, when 0.1W1≤X3≤0.3W1, it can prevent the setting width X3 of the second conductive semiconductor part from being too small, which leads to strict requirements on etching accuracy for forming a conductive semiconductor structure with a smaller setting width, thereby reducing the difficulty of etching; at the same time, it can also prevent that when the setting mode corresponding to the second conductive semiconductor part is an electrical setting, the setting width X3 is too small, so that the effective electrical contact area corresponding to the conductive semiconductor structure is also small, resulting in poor effect of reducing the risk of hot spots by setting a conductive semiconductor structure in the back contact battery. In addition, it can also prevent the electrode structure from being difficult to form on the area with a smaller width where the connection area is exposed outside the second conductive semiconductor part due to the large X3, which is conducive to reducing the manufacturing difficulty of the electrode structure, and can also prevent the electrode structure from being formed on the connection area with a smaller width, resulting in a larger transmission resistance corresponding to the electrode structure, thereby ensuring that the electrode structure has good transmission performance.

[0017] As a possible implementation scheme, along the extension direction of the spacing area, the width of the conductive semiconductor structure is W; the side effective electrical contact height of the first doped region and the second doped region electrically connected through the conductive semiconductor structure is Z; when the corresponding setting mode of the second conductive semiconductor part is an insulating setting, one sixteen thousandth of W ≤ Z ≤ one twenty-fifth of W.

[0018] In the case of adopting the above technical solution, at this time, regardless of whether the conductive semiconductor structure is set on at least one of the first doping region and the second doping region, the effective electrical contact area between the conductive semiconductor structure and the first doping region and the second doping region is only the effective electrical contact area between the side of the first doping region and the second doping region and the conductive semiconductor structure, that is, the product of W and Z. In the above case, the reverse breakdown voltage of the back contact battery and the leakage current under normal operation can be adjusted by adjusting the numerical values ​​of W and Z, which is conducive to improving the applicability of the back contact battery provided by the embodiment of the present invention in different application scenarios. In other words, W and Z meet the above-mentioned size relationship range, which can prevent the back contact battery from having a large leakage current under normal working conditions due to an unreasonable setting of the proportional relationship between W and Z, thereby ensuring that the back contact battery has a higher working performance; it can also prevent the back contact battery from having a small reaction breakdown voltage due to an unreasonable setting of the proportional relationship between W and Z, thereby ensuring that the back contact battery has a lower risk of hot spots.

[0019] As a possible implementation scheme, the width of the spacing region between the first doping region and the second doping region is D1; ​​along the extension direction of the spacing region, the width of the conductive semiconductor structure is W, and 0.5D1≤W≤3D1.

[0020] In the case of adopting the above technical solution, in the actual application process, not only the width of the conductive semiconductor structure along the extension direction of the spacing region will affect the effective electrical contact area between the conductive semiconductor structure and the first doping region and the second doping region respectively, but also the thickness of the conductive semiconductor structure (and, in the case where the conductive semiconductor structure is also electrically arranged above the portion of the first doping region and / or the second doping region that is away from the semiconductor substrate, the width of the portion of the conductive semiconductor structure arranged on the first doping region and / or the second doping region) may also affect the size of the above effective electrical contact area. It can be understood that, in the case where the doped semiconductor layers included in the first doping region and the second doping region are arranged at different heights on the semiconductor substrate, and the one with a smaller height is smaller than the height of the conductive semiconductor structure on the semiconductor substrate, and the one with a smaller height is opposite to the conductivity type of the conductive semiconductor structure, the greater the thickness of the conductive semiconductor structure, the greater the above effective electrical contact area. In the above case, the width W of the conductive semiconductor structure along the extension direction of the spacing region is within the above range, and a predetermined setting space can be reserved at least for the thickness range of the conductive semiconductor structure and / or the setting width range under the electrical setting, so as to prevent the thickness, width W and setting width of the conductive semiconductor structure under the electrical setting from being larger, resulting in a larger effective electrical contact area and causing a smaller reduction in the leakage loss of the back contact battery, thereby ensuring that the back contact battery has a relatively high working efficiency.

[0021] As a possible implementation scheme, the width of the connection region belonging to one of the first doping region and the second doping region and in contact with the conductive semiconductor structure is W1; the length of the strip doping region belonging to the other of the first doping region and the second doping region and in contact with the conductive semiconductor structure is W2. The width of the spacing region between the first doping region and the second doping region is D1. In addition, along the width direction of the spacing region, the length of the conductive semiconductor structure is D, and D1≤D≤D1+W1+W2.

[0022] In the case of adopting the above technical solution, after the format of the back contact battery is determined, the above D1, W1 and W2 are fixed values. Based on this, when the conductive semiconductor structure is at least partially located between a strip doping region included in one of the first doping region and the second doping region and an adjacent connection region included in the other, when D is equal to D1, the conductive semiconductor structure located between the strip doping regions and the connection regions with opposite conductivity types and adjacent to each other can be electrically contacted with the strip doping regions and the connection regions with opposite conductivity types and adjacent to each other along the arrangement direction of the first doping region and the second doping region, respectively, to ensure that the first doping region and the second doping region can be electrically connected through the conductive semiconductor structure; at the same time, the positive projection area of ​​the conductive semiconductor structure on the backlight side can also be precisely controlled to ensure that the hot spot risk corresponding to the back contact battery and the working efficiency under normal operation can accurately meet the working requirements. Secondly, the D value can also be greater than D1 and less than or equal to D1+W1+W2. In this case, the conductive semiconductor structure can not only be located between the strip-shaped doping region and the connecting region with opposite conductivity types and adjacent to each other, but can also be arranged on at least one of the strip-shaped doping region and the connecting region with opposite conductivity types and adjacent to each other, which can prevent the strict requirement of etching accuracy in order to obtain only the conductive semiconductor structure located only between the strip-shaped doping region and the connecting region with opposite conductivity types and adjacent to each other, thereby reducing the difficulty of etching. Furthermore, in the case where the conductive semiconductor structure is electrically arranged on the part in direct contact with itself in the first doping region and / or the second doping region, the size of the above-mentioned effective electrical contact area can be adjusted by adjusting the D value, which is conducive to balancing the reverse breakdown voltage and leakage loss of the back contact battery, and further conducive to making the back contact battery have good working performance.

[0023] As a possible implementation scheme, when the first doped region, the second doped region and the conductive semiconductor structure all include a doped semiconductor layer formed on the backlight surface, the height of the doped semiconductor layer included in one of the first doped region and the second doped region with a conductivity type opposite to that of the conductive semiconductor structure on the side of the backlight surface of the semiconductor substrate is less than the height of the doped semiconductor layer included in the other of the first doped region and the second doped region on the side of the backlight surface of the semiconductor substrate; part of the side surface of the doped semiconductor layer included in one of the first doped region and the second doped region with a conductivity type opposite to that of the conductive semiconductor structure is electrically in contact with the semiconductor substrate, and along the thickness direction of the semiconductor substrate, in the backlight surface, the difference between the height of the regional surface corresponding to the conductive semiconductor structure and the height of the regional surface corresponding to the doped semiconductor layer included in one of the first doped region and the second doped region with a conductivity type opposite to that of the conductive semiconductor structure is greater than or equal to 0.4μm and less than or equal to 2μm.

[0024] In the case of adopting the above technical solution, the doped semiconductor layer included in the first doping region is opposite to the conductive semiconductor structure in conductivity type. When forming the doped semiconductor layer included in the first doping region, the material for manufacturing the doped semiconductor layer included in the first doping region is difficult to fill in the corner caused by the height difference, which easily leads to the doped semiconductor layer included in the first doping region being difficult to fully contact with various parts of the surface of the semiconductor substrate (or, the semiconductor substrate and the conductive semiconductor structure) at the corner. Therefore, the difference between the height of the surface of the region corresponding to the conductive semiconductor structure on the backlight surface and the height of the surface of the region of the doped semiconductor layer with the opposite conductivity type of the conductive semiconductor structure is within the above range, and the part of the doped semiconductor layer included in the first doping region filled in the corner can be staggered with the side wall of the conductive semiconductor structure with the opposite conductivity type itself, ensuring that the conductive semiconductor structure has a larger side effective electrical contact area with the first doping region with the opposite conductivity type itself. When the doped semiconductor layer included in the second doping region is opposite to the conductive semiconductor structure in conductivity type, the corresponding beneficial effect is the same as the above effect, which will not be repeated here.

[0025] As a possible implementation solution,

[0026] When the above technical solution is adopted, the carriers collected by the first doping region and the second doping region need to be led out through the electrode structure that is in ohmic contact with itself. Based on this, along the extension direction of the strip doping region, the first doping region and the second doping region include a portion of the strip doping region along the extension direction thereof and need to be in direct ohmic contact with the electrode structure, and the ohmic contact area will occupy a certain length. In this case, when When the conductive semiconductor structure is formed, it is helpful to prevent the etching accuracy from being strictly required to form a conductive semiconductor structure with a smaller setting width due to the smaller setting width corresponding to the conductive semiconductor structure above the portion of the first doping region and / or the second doping region away from the semiconductor substrate, thereby reducing the etching difficulty; at the same time, it can also prevent the conductive semiconductor structure from being formed with a smaller setting width, which makes the effective electrical contact area corresponding to the conductive semiconductor structure smaller, thereby reducing the effect of reducing the risk of hot spots by setting the conductive semiconductor structure in the back contact battery. In addition, it is also helpful to prevent the electrode structure from being unable to make ohmic contact with the strip-shaped doping region included in the first doping region and the second doping region due to the larger setting width of the conductive semiconductor structure, thereby ensuring that the current collected by the first doping region and the second doping region can be led out through the electrode structure, thereby forming a photocurrent.

[0027] As a possible implementation scheme, in the second conductive semiconductor portion, the width of the portion disposed above the strip doping region included in the first doping region and / or the strip doping region included in the second doping region along the width direction of the strip doping region is X1. Along the extension direction of the spacing region, the width of the conductive semiconductor structure is W; when the corresponding configuration mode of the second conductive semiconductor portion is an electrical configuration, 0.03 mm ≤ X1 ≤ 0.2 mm; and / or 0.03 mm ≤ W ≤ 8 mm.

[0028] In the case of adopting the above technical solution, when X1 is within the above range, it is possible to prevent the high manufacturing precision requirements due to the small X1, thereby reducing the difficulty of manufacturing the back-contact battery; it is also possible to prevent the small effective electrical contact area corresponding to the conductive semiconductor structure due to the small X1, resulting in poor effect of reducing the risk of hot spots of the back-contact battery by setting the conductive semiconductor structure. In addition, it is possible to prevent the electrode structure from being difficult to manufacture and / or the contact resistance between the electrode structure and the strip-shaped doped region from being large due to the small width of the portion of the strip-shaped doped region reserved for ohmic contact with the electrode structure along its own width direction, which is beneficial to improving the yield of the back-contact battery and the contact performance between the electrode structure and the strip-shaped doped region. In addition, the beneficial effects of W within the above range can be referred to in the previous text and will not be repeated here.

[0029] As a possible implementation scheme, the back contact battery includes a plurality of conductive semiconductor structures. Adjacent conductive semiconductor structures are arranged at intervals. In this case, it is possible to prevent a large local leakage current between the first doped region and the second doped region caused by adjacent different conductive semiconductor structures contacting each other.

[0030] As a possible implementation scheme, when the back contact cell is a whole-piece back contact cell, the number of conductive semiconductor structures included in the back contact cell is greater than or equal to 30 and less than or equal to 8000; or, when the back contact cell is a one-N slice back contact cell, the number of conductive semiconductor structures included in the back contact cell is greater than or equal to 30 / N and less than or equal to 8000 / N; N is a positive integer greater than or equal to 2.

[0031] In the case of adopting the above technical solution, it can be understood that, when the size of each conductive semiconductor structure is fixed, the more the number of conductive semiconductor structures formed on one side of the backlight surface, the greater the sum of the positive projection areas of the conductive semiconductor structures on one side of the backlight surface. Secondly, within a certain range, the more the number of conductive semiconductor structures, the lower the reverse breakdown voltage corresponding to the back contact battery, but beyond the corresponding range, even if more conductive semiconductor structures are set on the side of the backlight surface, the change amplitude of the reverse breakdown voltage corresponding to the back contact battery is small or even no longer changes. When the number of conductive semiconductor structures increases to a larger range, the working efficiency of the back contact battery will decrease with the increase of leakage current. Based on this, in the case where the back contact battery is a whole back contact battery, the number of conductive semiconductor structures included in the back contact battery is set to be greater than or equal to 30 and less than or equal to 8000, which can prevent the reverse breakdown voltage corresponding to the back contact battery from being reduced due to the small number of conductive semiconductor structures, and ensure that the hot spot risk of the back contact battery can be reduced to within the working requirements. In addition, it can also prevent the working efficiency of the photovoltaic module including the back contact battery provided by the present invention from being reduced due to the setting of more conductive semiconductor structures. As for the beneficial effect that when the back contact battery is a one-N slice back contact battery, the number of conductive semiconductor structures included in the back contact battery is greater than or equal to 30 / N and less than or equal to 8000 / N, you can refer to the analysis of the beneficial effect that when the back contact battery is a whole back contact battery, the number of conductive semiconductor structures included in the back contact battery is greater than or equal to 30 and less than or equal to 8000 mentioned above, and no further details will be given here.

[0032] As a possible implementation scheme, the orthographic projection areas of different conductive semiconductor structures on the backlight side are equal.

[0033] When the above-mentioned technical solution is adopted, when the orthographic projection areas of different conductive semiconductor structures on the backlight side are equal, it is beneficial to make the corresponding leakage currents of the first doping region and the second doping region equal after being electrically connected to different conductive semiconductor structures, thereby making the reverse breakdown voltages of the built-in diodes arranged in different areas between the first doping region and the second doping region equal, thereby preventing the problem of battery burning due to local heat concentration when the back contact battery is blocked, and further reducing the risk of hot spots in photovoltaic modules including the back contact battery provided by the present invention.

[0034] As a possible implementation scheme, different conductive semiconductor structures are evenly distributed on one side of the backlight surface. In this case, it is beneficial to make the reverse breakdown voltage of the built-in diode formed between different areas of the first doping region and the corresponding areas of the second doping region after the conductive semiconductor structure is set equal, thereby preventing the problem of battery burning due to local heat concentration when the back contact battery is blocked, and further reducing the risk of hot spots in the photovoltaic module including the back contact battery provided by the present invention.

[0035] As a possible implementation scheme, different conductive semiconductor structures are distributed in a matrix on one side of the backlight surface. Adjacent rows of the conductive semiconductor structures distributed in a matrix are aligned or staggered. In this case, the distribution of different conductive semiconductor structures on one side of the backlight surface is relatively regular, and adjacent rows of the conductive semiconductor structures distributed in a matrix also have two distribution modes: alignment and staggered arrangement. This helps to reduce the difficulty of manufacturing the conductive semiconductor structure, and also helps to evenly distribute the conductive semiconductor structure on one side of the backlight surface, further preventing the problem of battery burning due to local heat concentration when the back contact battery is blocked.

[0036] As a possible implementation scheme, in the case where adjacent rows of conductive semiconductor structures distributed in a matrix are staggered, the staggered distance between two adjacent rows of conductive semiconductor structures is equal to half of the distance between the geometric centers of two adjacent conductive semiconductor structures in the same row. In this case, it is beneficial to make the distribution density of the conductive semiconductor structures between different areas of the first doping region and the corresponding areas of the second doping region roughly the same, and prevent the problem that the back contact battery may be blocked due to local heat concentration and cause the battery to burn due to the long area between the first doping region and the second doping region that is physically isolated by an insulating groove or insulating material.

[0037] As a possible implementation scheme, the conductive semiconductor structure has the same conductivity type as the first doping region and is continuous as a whole. Or, the conductive semiconductor structure has the same conductivity type as the second doping region and is continuous as a whole.

[0038] In the case of adopting the above technical solution, in the actual manufacturing process, the same process can be used to manufacture the conductive semiconductor structure while manufacturing the first doping region or the second doping region. For example: in the first doping region or the second doping region, the first doping region or the second doping region where only a local area of ​​the backlight surface is set can be obtained respectively by selectively etching the entire layer of doped semiconductor material layer formed on one side of the backlight surface. Based on this, when the conductive semiconductor structure is continuous with the first doping region or the second doping region, the conductive semiconductor structure and the first doping region (or at least part of the second doping region) are formed based on the same doped semiconductor material layer, which reduces the manufacturing cost of the back contact battery, and does not need to use deposition and etching processes to form the conductive semiconductor structure separately, which simplifies the manufacturing process of the back contact battery and improves the manufacturing efficiency of the back contact battery.

[0039] As a possible implementation, at least one of the first doped region, the second doped region and the conductive semiconductor structure includes a doped semiconductor layer located on the backlight surface of the semiconductor substrate; and the back contact cell further includes a passivation layer located between the semiconductor substrate and the doped semiconductor layer. In this case, the passivation layer can passivate the corresponding area of ​​the backlight surface of the semiconductor substrate to reduce the carrier recombination rate.

[0040] As a possible implementation scheme, the doped semiconductor layer includes: at least one of a doped polycrystalline silicon layer, a doped single crystal silicon layer, a doped amorphous silicon layer, a doped microcrystalline silicon layer and a doped nanocrystalline silicon layer; and / or the passivation layer includes a tunneling passivation layer or an intrinsic amorphous silicon layer.

[0041] In a second aspect, the present invention provides a photovoltaic module, which includes the solar cell provided by the first aspect and various implementations thereof.

[0042] The beneficial effects of the second aspect of the present invention and its various implementations can be analyzed by referring to the beneficial effects of the first aspect and its various implementations, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0044] Figure 1 A schematic diagram of the scope of the selective etching area in the related art and a schematic diagram of the distribution of the first doped area and the second doped area on the backlight side after selective etching;

[0045] Figure 2 A schematic diagram of a distribution relationship between the first doping region and the second doping region on the backlight side of the back contact cell provided in an embodiment of the present invention;

[0046] Figure 3 A schematic diagram of a first distribution of a conductive semiconductor structure between two adjacent strip-shaped doped regions of opposite conductivity types in a back-contact battery provided by an embodiment of the present invention;

[0047] Figure 4 A schematic diagram of a first distribution of a conductive semiconductor structure between adjacent strip-shaped doped regions and a connecting region of opposite conductivity types in a back-contact battery provided by an embodiment of the present invention;

[0048] Figure 5 A first longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0049] Figure 6 A second longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0050] Figure 7 A schematic diagram of a second distribution of a conductive semiconductor structure between two adjacent strip-shaped doped regions of opposite conductivity types in a back-contact battery provided by an embodiment of the present invention;

[0051] Figure 8 A schematic diagram of a third distribution of a conductive semiconductor structure between two adjacent strip-shaped doped regions of opposite conductivity types in a back contact battery provided by an embodiment of the present invention;

[0052] Fig. 9 A schematic diagram of a fourth distribution of the conductive semiconductor structure between two adjacent strip-shaped doped regions of opposite conductivity types in a back-contact battery provided by an embodiment of the present invention;

[0053] Fig.10 A schematic diagram of a second distribution of the conductive semiconductor structure between adjacent strip-shaped doped regions and connecting regions of opposite conductivity types in a back-contact battery provided by an embodiment of the present invention;

[0054] Fig.11 A schematic diagram of the selective etching area range in an embodiment of the present invention and a schematic diagram of the distribution of the first doped region, the second doped region and the conductive semiconductor structure on the backlight side after selective etching;

[0055] Fig.12 A third longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0056] Fig.13 A fourth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0057] Fig.14A fifth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0058] Fig.15 A sixth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0059] Fig.16 A seventh longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0060] Fig.17 An eighth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0061] Fig.18 A ninth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0062] Fig.19 A tenth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0063] Fig. 20 An eleventh longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0064] Fig.21 A twelfth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0065] Fig. 22 A thirteenth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0066] Fig.23 A fourteenth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0067] Fig.24 A fifteenth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0068] Fig.25 A sixteenth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0069] Fig.26 A seventeenth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0070] Fig. 27 An eighteenth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0071] Fig.28A nineteenth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0072] Fig.29 A twentieth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0073] Fig.30 A twenty-first longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0074] Fig.31 A twenty-second longitudinal cross-sectional schematic diagram of a portion of the structure of a back-contact battery provided by an embodiment of the present invention;

[0075] Fig.32 A twenty-third longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0076] Fig.33 A twenty-fourth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0077] Fig.34 A twenty-fifth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0078] Fig.35 A twenty-sixth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0079] Fig.36 A twenty-seventh longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0080] Fig.37 A twenty-eighth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0081] Fig.38 A twenty-ninth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0082] Fig.39 A 30th longitudinal cross-sectional schematic diagram of a part of the structure of a back contact battery provided by an embodiment of the present invention;

[0083] Fig.40 A thirty-first longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0084] Fig.41 A thirty-second longitudinal cross-sectional schematic diagram of a portion of the structure of a back-contact battery provided by an embodiment of the present invention;

[0085] Fig.42 A thirty-third longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0086] Fig.43 A thirty-fourth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0087] Fig.44 A thirty-fifth longitudinal cross-sectional schematic diagram of a portion of the structure of a back-contact battery provided by an embodiment of the present invention;

[0088] Fig.45 A thirty-sixth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0089] Fig.46 A thirty-seventh longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0090] Fig.47 A thirty-eighth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0091] Fig.48 A thirty-ninth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0092] Fig.49 A fortieth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0093] Fig.50 A schematic diagram of a first distribution of the conductive semiconductor structure on the backlight side of a back-contact battery provided by an embodiment of the present invention;

[0094] Fig.51 A schematic diagram of a second distribution of the conductive semiconductor structure on the backlight side of the back contact battery provided by an embodiment of the present invention;

[0095] Fig.52 A graph showing the relationship between the number of conductive semiconductor structures and the leakage current, hot spot temperature and reverse breakdown voltage when W is equal to 200 microns and D1 is equal to 100 microns in a back contact battery provided by an embodiment of the present invention;

[0096] Fig.53 A graph showing the relationship between the number of conductive semiconductor structures and the change in working efficiency when W is equal to 200 microns and D1 is equal to 100 microns in a back contact battery provided by an embodiment of the present invention;

[0097] Fig.54is a graph showing the relationship between the number of conductive semiconductor structures and the leakage current, hot spot temperature and reverse breakdown voltage when W is equal to 680 microns and D1 is equal to 100 microns;

[0098] Fig.55 is a graph showing the relationship between the number of conductive semiconductor structures and the change in working efficiency when W is equal to 680 microns and D1 is equal to 100 microns;

[0099] Fig.56 A curve diagram showing the relationship between the reverse current and the reverse voltage corresponding to embodiments 1 to 4 in the embodiments of the present invention;

[0100] Fig.57 A schematic diagram of a ninth distribution of the conductive semiconductor structure between two adjacent strip-shaped doped regions of opposite conductivity types in a back-contact battery provided by an embodiment of the present invention;

[0101] Fig.58 A schematic diagram of a tenth distribution of a conductive semiconductor structure between two adjacent strip-shaped doped regions of opposite conductivity types in a back contact battery provided by an embodiment of the present invention;

[0102] Fig.59 A schematic diagram of an eleventh distribution of a conductive semiconductor structure between two adjacent strip-shaped doped regions of opposite conductivity types in a back-contact battery provided by an embodiment of the present invention;

[0103] Fig.60 A schematic diagram of a twelfth distribution of a conductive semiconductor structure between two adjacent strip-shaped doped regions of opposite conductivity types in a back-contact battery provided by an embodiment of the present invention;

[0104] Fig.61 A schematic diagram of a thirteenth distribution of a conductive semiconductor structure between two adjacent strip-shaped doped regions of opposite conductivity types in a back-contact battery provided by an embodiment of the present invention;

[0105] Fig.62 A schematic diagram of a fourteenth distribution situation of a conductive semiconductor structure between two adjacent strip-shaped doped regions of opposite conductivity types in a back-contact battery provided by an embodiment of the present invention;

[0106] Fig.63 A fifth longitudinal cross-sectional schematic diagram of the middle structure of a back contact battery provided by an embodiment of the present invention;

[0107] Fig.64 A fortieth longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0108] Fig.65 A forty-first longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0109] Fig.66 A forty-second longitudinal cross-sectional schematic diagram of a portion of the structure of a back-contact battery provided by an embodiment of the present invention;

[0110] Fig.67 A forty-third longitudinal cross-sectional schematic diagram of a portion of the structure of a back contact battery provided by an embodiment of the present invention;

[0111] Fig.68 The forty-fourth schematic longitudinal cross-sectional view of a portion of the structure in the back contact battery provided in an embodiment of the present invention.

[0112] Figure numerals: 11 is a first doping region, 12 is a second doping region, 13 is a conductive semiconductor structure, 14 is a strip doping region, 15 is a connection region, 16 is a physical spacing layer, 17 is a first conductive semiconductor portion, 18 is a second conductive semiconductor portion, 19 is a surface passivation layer, 20 is an electrode structure, and 21 is a third conductive semiconductor portion. DETAILED DESCRIPTION

[0113] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present disclosure. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0114] Various structural schematic diagrams according to embodiments of the present disclosure are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may further design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0115] In the context of the present disclosure, when a layer / element is referred to as being "on" another layer / element, the layer / element may be directly on the other layer / element, or there may be an intermediate layer / element between them. In addition, if a layer / element is "on" another layer / element in one orientation, then when the orientation is reversed, the layer / element may be "under" the other layer / element. In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0116] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined. The meaning of "several" is one or more, unless otherwise clearly and specifically defined.

[0117] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0118] The hot spot effect refers to the situation where the solar cell in a photovoltaic module is broken, cracked, welded, or has quality problems, or there are shadows, bird droppings, dust, or other obstructions on the solar cell, causing the problematic solar cell to be used as a load to consume the energy generated by other solar cells connected in series with it, thereby causing local temperature rise. Moreover, within a certain range, the higher the reverse breakdown voltage of the solar cell, the higher the temperature generated after the hot spot problem occurs.

[0119] like Figure 1 As shown, in the existing back-contact cells, the two doping regions with opposite conductivity types that are co-located on the backlight side are completely isolated by the spacing area to reduce leakage from the cell end and improve the working efficiency of a single back-contact cell. However, from the perspective of the module end, the two doping layers with opposite conductivity types are completely isolated, which will make the back-contact cell have a higher reverse breakdown voltage, and thus cause the photovoltaic module including the existing back-contact cell to have a higher risk of hot spots during actual operation.

[0120] In response to the above technical problems, technicians in this field changed the continuous insulating groove located on the spacing area in the original back contact cell into a discontinuous insulating groove, so that the two doping layers with opposite conductivity types are electrically connected through the parts disconnected by the insulating groove, thereby reducing the reverse breakdown voltage of the back contact cell and reducing the risk of hot spots in the actual operation of photovoltaic modules including existing back contact cells.

[0121] However, the width of the unbroken portion of the spacing area in the existing back-contact battery along its own extension direction is set unreasonably, resulting in a large leakage current of the back-contact battery from the battery end, thereby making the working efficiency of the back-contact battery poor.

[0122] In order to solve the above technical problems, in the first aspect, an embodiment of the present invention provides a back contact battery. The back contact battery can be a whole back contact battery or a one-N sliced ​​back contact battery. The division multiple N of the above sliced ​​back contact battery can be any positive integer greater than or equal to 2.

[0123] Specifically, if Figures 2 to 4 As shown, the back contact cell provided by the embodiment of the present invention includes: a semiconductor substrate (not shown in the figure), a first doping region 11, a second doping region 12 and at least one conductive semiconductor structure 13. Each conductive semiconductor structure 13 is at least partially located between the first doping region 11 and the second doping region 12, and only a part of the first doping region 11 and only a part of the second doping region 12 are respectively in electrical contact with at least one conductive semiconductor structure 13. The first doping region 11 and the second doping region 12 have opposite conductivity types, and the conductive semiconductor structure 13 has an opposite conductivity type to that of one of the first doping region 11 and the second doping region 12. Figure 2 As shown, the first doping region 11 and the second doping region 12 each include a plurality of strip doping regions 14 and at least one connection region 15. The strip doping regions 14 included in the first doping region 11 and the strip doping regions 14 included in the second doping region 12 are parallel and alternately distributed on the backlight side of the semiconductor substrate; each connection region 15 is electrically connected to a corresponding strip doping region 14 of the same conductivity type as itself; the extension direction of the connection region 15 is different from the extension direction of the strip doping region 14. Figure 2 and Figure 4 As shown, at least one conductive semiconductor structure 13 is at least partially located between a strip-shaped doped region 14 included in one of the first doped region 11 and the second doped region 12 and an adjacent connecting region 15 included in the other one.

[0124] It should be noted that the extension direction of the above-mentioned spacing region is parallel to the backlight surface of the semiconductor substrate and perpendicular to the width of the spacing region. The width direction of the conductive semiconductor structure is parallel to the distribution direction of the strip doping regions of opposite conductivity types.

[0125] When the above technical solution is adopted, Figure 2 As shown, the first doping region 11 and the second doping region 12 of opposite conductivity types are distributed on the backlight side of the semiconductor substrate to effectively shunt carriers when the back contact cell is in operation, thereby facilitating the formation of photocurrent. Figure 3 and Figure 4As shown, the back contact battery provided by the embodiment of the present invention also includes at least one conductive semiconductor structure 13 at least partially located between the first doping region and the second doping region. Based on this, since each conductive semiconductor structure 13 has conductive properties, and the conductive type of the conductive semiconductor structure 13 is opposite to the conductive type of one of the first doping region 11 and the second doping region 12, when the conductive semiconductor structure 13 is electrically in contact with a portion of the first doping region and a portion of the second doping region, respectively, the first doping region and the second doping region can be electrically connected by manufacturing a local leakage point to form a built-in diode with a lower reverse breakdown voltage, thereby facilitating the back contact battery to have a lower reverse breakdown voltage when it is blocked. In addition, only a portion of the first doping region and only a portion of the second doping region are electrically in contact with the above-mentioned at least one conductive semiconductor structure 13. In other words, part of the first doping region and the corresponding part of the second doping region are respectively in electrical contact with the at least one conductive semiconductor structure 13, while the remaining areas of the first doping region and the corresponding areas of the second doping region are still physically isolated by insulating grooves or insulating materials, etc., to prevent the leakage current of the back contact battery under normal working conditions from being large due to the conductive semiconductor structure 13 being arranged between all the areas of the first doping region and the second doping region, resulting in low working efficiency of the back contact battery, thereby ensuring that the photovoltaic module including the back contact battery provided by the embodiment of the present invention has a high photoelectric conversion efficiency in the forward voltage region. Figure 2 and Figure 4 As shown, at least a portion of at least one conductive semiconductor structure 13 is located between a strip-shaped doping region 14 included in one of the first doping region 11 and the second doping region 12 and an adjacent connecting region 15 included in the other, so that the reverse breakdown voltage and forward leakage loss of the back-contact battery can be regulated by adjusting the size of the conductive semiconductor structure 13 according to the needs of actual application scenarios, thereby improving the working performance of the back-contact battery provided in the embodiment of the present invention.

[0126] In actual application, the semiconductor substrate may be a substrate made of any semiconductor material such as a silicon substrate, a silicon germanium substrate, a germanium substrate or a gallium arsenide substrate.

[0127] For the first doping region and the second doping region, in terms of conductivity type, the first doping region can be an N-type doping region, and the second doping region is a P-type doping region. Alternatively, the first doping region can also be a P-type doping region, and the second doping region is an N-type doping region. Secondly, the embodiment of the present invention does not specifically limit the thickness (or depth) H1 of the first doping region and the thickness (or depth) H2 of the second doping region, as long as they can be applied to the back contact battery provided in the embodiment of the present invention.

[0128] In addition, in terms of the formation position, the first doping region and the second doping region can both be formed on the backlight side of the semiconductor substrate; in this case, the surface of the first doping region facing away from the light side of the semiconductor substrate and the surface of the second doping region facing away from the light side of the semiconductor substrate can both be flush with the backlight side of the semiconductor substrate, or there can be a height difference between the two. The depth of the first doping region and the second doping region refers to the doping depth corresponding to themselves. Secondly, the materials of the first doping region and the second doping region are the same as the material of the semiconductor substrate.

[0129] Alternatively, the first doped region and / or the second doped region may also both include a doped semiconductor layer formed on the backlight surface of the semiconductor substrate. In this case, the material of the doped semiconductor layer may include any semiconductor material such as silicon, silicon germanium, germanium or gallium arsenide. In terms of the arrangement of the material, the crystalline phase of the doped semiconductor layer may be amorphous, microcrystalline, nanocrystalline, single crystal or polycrystalline, etc. Specifically, the material of the doped semiconductor layer included in the first doped region and the doped semiconductor layer included in the second doped region may be the same or different.

[0130] Among them, when the first doped region includes a doped semiconductor layer located on the backlight surface of the semiconductor substrate, the doped semiconductor layer included in the first doped region can be directly formed on a partial area of ​​the backlight surface of the semiconductor substrate; or, the back contact battery provided by the embodiment of the present invention also includes a passivation layer located between the doped semiconductor layer included in the first doped region and the semiconductor substrate. The material of the passivation layer can be determined according to the material of the doped semiconductor layer included in the first doped region and the actual application scenario, and is not specifically limited here. For example: when the doped semiconductor layer included in the first doped region is a doped polycrystalline silicon layer, the passivation layer is a tunneling passivation layer. For another example: when the doped semiconductor layer included in the first doped region includes a doped amorphous silicon layer and / or a doped microcrystalline silicon layer, the passivation layer is an intrinsic amorphous silicon layer.

[0131] Secondly, when the doped semiconductor layer included in the first doped region is located on the backlight surface of the semiconductor substrate, the first doped region may also include a sub-doped region formed in a corresponding region of the semiconductor substrate by diffusion. Wherein, when there is a passivation layer between the doped semiconductor layer included in the first doped region and the semiconductor substrate, the first doped region may also include a sub-doped region formed in a corresponding region of the passivation layer by diffusion.

[0132] When the doped semiconductor layer included in the second doping region is located on the backlight surface of the semiconductor substrate, the doped semiconductor layer included in the second doping region can be directly formed on a partial area of ​​the backlight surface of the semiconductor substrate; or, the back contact battery provided in the embodiment of the present invention also includes a passivation layer located between the doped semiconductor layer included in the second doping region and the semiconductor substrate. The material of the passivation layer can be determined according to the material of the doped semiconductor layer included in the second doping region and the actual application scenario, and is not specifically limited here. For example: when the doped semiconductor layer included in the second doping region is a doped amorphous silicon layer and / or a doped microcrystalline silicon layer, the passivation layer can be an intrinsic amorphous silicon layer. For another example: when the doped semiconductor layer included in the second doping region is a doped polycrystalline silicon layer, the passivation layer is a tunneling passivation layer.

[0133] Secondly, when the second doped region includes a doped semiconductor layer located on the backlight surface of the semiconductor substrate, the second doped region may also include a sub-doped region formed in a corresponding region of the semiconductor substrate by diffusion. Wherein, when there is a passivation layer between the doped semiconductor layer included in the second doped region and the semiconductor substrate, the second doped region may also include a sub-doped region formed in a corresponding region of the passivation layer by diffusion.

[0134] Specifically, when a passivation layer is provided between the doped semiconductor layer included in the first doped region and the semiconductor substrate, and between the doped semiconductor layer included in the second doped region and the semiconductor substrate, the materials and / or thicknesses of the two passivation layers may be the same or different.

[0135] Exemplarily, in the back contact cell provided by the embodiment of the present invention, the semiconductor substrate is a P-type semiconductor substrate, and the first doping region and the second doping region both include a doped semiconductor layer formed on the backlight surface of the semiconductor substrate. The doped semiconductor layer included in the first doping region and the doped semiconductor layer included in the second doping region are both doped polysilicon layers, and a tunnel passivation layer is formed between the doped semiconductor layer included in the first doping region and the doped semiconductor layer included in the second doping region and the semiconductor substrate, respectively.

[0136] In terms of morphology, the embodiment of the present invention does not specifically limit the morphology of the first doping region and the second doping region, as long as they can be applied to the back contact battery provided by the embodiment of the present invention.

[0137] For example, Figure 2 As shown, the first doping regions 11 and the second doping regions 12 may be distributed alternately in an interdigitated manner.

[0138] For the above-mentioned conductive semiconductor structure, the embodiment of the present invention does not specifically limit the morphology of the conductive semiconductor structure. For example, the orthographic projection of each conductive semiconductor structure on the backlight side can be a rectangular, trapezoidal, hexagonal or beaded shape. Secondly, the embodiment of the present invention does not specifically limit the conductivity type and impurity doping concentration of the conductive semiconductor structure, as long as the first doping region and the second doping region can be electrically connected.

[0139] From the perspective of actual manufacturing, the above-mentioned conductive semiconductor structure can be formed on the backlight side of the semiconductor substrate separately from the first doping region and the second doping region, that is, the conductive semiconductor structure is not integrally continuous with the first doping region and the second doping region. At this time, the material of the conductive semiconductor structure can be the same as the material of the first doping region or the second doping region, or it can be different. The doping concentration of impurities in the conductive semiconductor structure can be greater than, equal to, or less than the doping concentration of impurities in either the first doping region or the second doping region. In addition, in this case, when the conductive semiconductor structure is formed on the semiconductor substrate, at least part of the conductive semiconductor structure can be directly located on the semiconductor substrate, or a passivation layer can be formed between the conductive semiconductor structure and the semiconductor substrate. The material of the passivation layer can be determined according to the material of the conductive semiconductor structure. For example: when the conductive semiconductor structure is a doped amorphous silicon layer and / or a doped microcrystalline silicon layer, the passivation layer can be an intrinsic amorphous silicon layer. For another example: when the conductive semiconductor structure is a doped polycrystalline silicon layer, the passivation layer is a tunneling passivation layer. Specifically, when a passivation layer is provided between the first doped region and / or the second doped region and the substrate, and between the conductive semiconductor structure and the semiconductor substrate, the material and / or thickness of at least two passivation layers may be the same or different.

[0140] It can also be: Figure 5 As shown, the conductive semiconductor structure 13 has the same conductivity type as the first doping region 11 and is continuous as a whole; at this time, the material and impurity doping concentration of the conductive semiconductor structure 13 are respectively the same as the material and impurity doping concentration of the first doping region 11 ( Figure 5 for Figure 3 Schematic diagram of the longitudinal section along the A-A' direction). Or, Figure 6 As shown, the conductive semiconductor structure 13 has the same conductivity type as the second doping region 12 and is continuous with the second doping region 12. At this time, the material and impurity doping concentration of the conductive semiconductor structure 13 are respectively the same as the material and impurity doping concentration of the second doping region 12.

[0141] Wherein, when the conductive semiconductor structure includes a doped semiconductor layer located on the backlight surface of the semiconductor substrate, the region corresponding to the conductive semiconductor structure may include the region where the doped semiconductor layer is located, and may also include a sub-doped region formed by diffusion in the corresponding region of the semiconductor substrate. Wherein, when there is a passivation layer between the doped semiconductor layer included in the conductive semiconductor structure and the semiconductor substrate, the region where the conductive semiconductor structure is located may also include a sub-doped region formed by diffusion in the corresponding region of the passivation layer.

[0142] It is worth noting that in the actual manufacturing process, the same process can be used to manufacture the conductive semiconductor structure while manufacturing the first doping region or the second doping region. For example: when the first doping region or the second doping region is integrally continuous with the conductive semiconductor structure, the first doping region or the second doping region located only on the local area of ​​the backlight surface can be obtained by selectively etching the entire layer of doped semiconductor material layer formed on one side of the backlight surface. Based on this, when the conductive semiconductor structure is integrally continuous with the second doping region or the first doping region, the conductive semiconductor structure and the first doping region (or the second doping region) are formed based on the same doped semiconductor material layer, which reduces the manufacturing cost of the back contact battery, and does not need to use deposition and etching processes to form the conductive semiconductor structure separately, which simplifies the manufacturing process of the back contact battery and improves the manufacturing efficiency of the back contact battery. When the conductive semiconductor structure is not integrally continuous with the first doping region and the second doping region, a conductive semiconductor structure that meets the corresponding material and doping concentration requirements can be formed according to the needs of the actual application scenario. There is no need to make the material and doping concentration of the conductive semiconductor structure only the same as the first doping region or the second doping region that is integrally continuous with it, thereby improving the applicability of the back contact battery provided by the embodiment of the present invention in different application scenarios.

[0143] In terms of setting the relative height, the backlight surface of the semiconductor substrate may be a plane, and in this case, the first doped region, the second doped region and the conductive semiconductor structure are flush with the surfaces on one side of the backlight surface.

[0144] Alternatively, the first doping region and the second doping region have a height difference greater than 0 between their surfaces corresponding to the backlight side of the semiconductor substrate. In this case, the smaller surface height of the first doping region and the second doping region corresponding to the backlight side of the semiconductor substrate may be the same as the surface height of the conductive semiconductor structure corresponding to the backlight side, or the larger surface height of the first doping region and the second doping region corresponding to the backlight side of the semiconductor substrate may be the same as the surface height of the conductive semiconductor structure corresponding to the backlight side, or the surface height of the conductive semiconductor structure corresponding to the backlight side may be between the two surface heights of the first doping region and the second doping region corresponding to the backlight side of the semiconductor substrate.

[0145] In addition, the specific formation position of the portion of each conductive semiconductor structure between the first doping region and the second doping region can be determined according to the morphology of the first doping region and the second doping region, and the actual application scenario, as long as the first doping region and the second doping region can be electrically connected through the conductive semiconductor structure.

[0146] Secondly, if Figures 3 to 6 As shown, the conductive semiconductor structure 13 may be located only between the first doping region 11 and the second doping region 12 .

[0147] Or, if Figures 7 to 9 As shown, the conductive semiconductor structure 13 may also include a first conductive semiconductor portion 17 and a second conductive semiconductor portion 18 in electrical contact. The first conductive semiconductor portion is located in the spacing region, and the second conductive semiconductor portion 18 is disposed above a portion of the first doping region and / or the second doping region that is away from the semiconductor substrate.

[0148] Among them, from the perspective of setting objects, such as Figure 7 As shown, the second conductive semiconductor portion 18 may be disposed only on the first doped region. Figure 8 As shown, the second conductive semiconductor portion 18 may also be disposed only on the second doping region. Fig. 9 As shown, the second conductive semiconductor portion 18 may also be disposed on both the first doped region and the second doped region. In this case, there are multiple options for the formation range of the conductive semiconductor structure 13, which can prevent the strict requirement of etching accuracy for obtaining only the conductive semiconductor structure 13 located only between the first doped region and the second doped region, thereby reducing the etching difficulty. At the same time, it can also ensure that the first doped region can be partially electrically connected through the conductive semiconductor structure 13.

[0149] In terms of setting direction, Figure 2 As shown, in the case where the first doping region 11 and the second doping region 12 are alternately distributed in an interdigitated manner, as shown in FIG. Figures 7 to 9 As shown, the second conductive semiconductor portion 18 can be disposed on the strip doping region 14 included in the first doped semiconductor and / or the strip doping region 14 included in the second doping region along the width direction of the strip doping region 14. In this case, the width of the portion disposed on the corresponding strip doping region 14 along the width direction of the strip doping region 14 in the second conductive semiconductor portion 18 is defined as X1. Alternatively, as Fig.10 As shown, the second conductive semiconductor portion 18 may also be disposed on the strip-shaped doped region 14 included in the first doped semiconductor and / or the strip-shaped doped region 14 included in the second doped region along the extension direction of the strip-shaped doped region 14. In this case, the width of the portion of the second conductive semiconductor portion 18 disposed on the corresponding strip-shaped doped region 14 along the extension direction of the strip-shaped doped region 14 is defined as X2. Alternatively, as Fig.10As shown, the second conductive semiconductor portion 18 can also be arranged on the connection region 15 included in the first doped semiconductor and / or the connection region 15 included in the second doped region along the extension direction of the strip doping region 14. At this time, it is defined that in the second conductive semiconductor portion, the setting width of the portion arranged on the corresponding connection region 15 along the extension direction of the strip doping region 14 is X3.

[0150] In terms of arrangement distribution, when the conductive semiconductor structure further includes the first conductive semiconductor portion and the second conductive semiconductor portion, as Figures 7 to 9 As shown, the second conductive semiconductor portion 18 may be disposed above one side of the first doping region and / or the second doping region along the width direction; or Fig.11 As shown, the second conductive semiconductor portion 18 may be disposed above both sides of the first doping region 11 and / or the second doping region 12 along the width direction.

[0151] In terms of setting method, Figure 12 to Figure 13 As shown, the second conductive semiconductor portion 18 may be in direct contact with the first doping region 11 and / or the second doping region 12. At this time, not only the sidewalls of the conductive semiconductor structure 13 are in electrical contact with the first doping region 11 and the second doping region 12, but also the portion of the conductive semiconductor structure 13 disposed on the first doping region 11 and / or the second doping region 12 is in electrical contact with the first doping region 11 and / or the second doping region 12.

[0152] Or, in the actual manufacturing process, such as Fig.14 As shown, corresponding physical spacing layers 16 may be formed on the first doping region 11 and the second doping region 12, respectively. The physical spacing layer 16 may be formed when the first doping region 11 and the second doping region 12 are manufactured by a diffusion process, or may be formed to prevent the formed first doping region 11 and the second doping region 12 from being affected by subsequent processes (e.g., in order to prevent the formed first doping region 11 from being inverted when the second doping region 12 is manufactured on the backlight side after the first doping region 11 is formed, a physical spacing layer 16 is formed on its surface). Based on this, the above-mentioned physical spacing layer 16 may be a conductive layer, and at this time, the corresponding part of the conductive semiconductor structure 13 is electrically arranged with the first doping region 11 and / or the second doping region 12, and the corresponding electrical contact of the conductive semiconductor structure 13 may refer to the corresponding electrical contact during the above-mentioned direct contact. Alternatively, the physical spacing layer 16 may be a non-conductive insulating layer. In this case, regardless of whether the conductive semiconductor structure 13 is disposed on at least one of the first doping region 11 and the second doping region 12, the conductive semiconductor structure 13 is only electrically contacted with the side surfaces of the first doping region 11 and the second doping region 12, respectively. That is, reference may be made to the electrical contact situation described above when the conductive semiconductor structure 13 is only located between the first doping region 11 and the second doping region 12.

[0153] From the perspective of the configuration structure, the contact surface between the first doped region and the second doped region, which has an opposite conductivity type to the conductive semiconductor structure, and the conductive semiconductor structure includes a side effective electrical contact surface. The side effective electrical contact surface may be parallel to the thickness direction of the semiconductor substrate, or may have a certain angle with the thickness direction of the semiconductor substrate. The embodiment of the present invention does not specifically limit the size of the angle.

[0154] As for the specific structure of the above conductive semiconductor structure, it can be determined according to the formation positions of the first doping region and the second doping region on the backlight side of the semiconductor substrate. Specifically, it can be divided into the following four cases for explanation:

[0155] The first one, such as Fig.67 As shown, when one of the first doping region 11 and the second doping region 12 includes a doped semiconductor layer located on the backlight surface of the semiconductor substrate, and the other is located in the semiconductor substrate, the conductive semiconductor structure 13 may include the above-mentioned first conductive semiconductor portion 17 and second conductive semiconductor portion 18. The second conductive semiconductor portion 18 is disposed above a portion of the first doping region 11 and the second doping region 12 located in the semiconductor substrate and facing away from the semiconductor substrate.

[0156] The second type, such as Fig.68 As shown, when one of the first doped region 11 and the second doped region 12 includes a doped semiconductor layer located on the backlight surface of the semiconductor substrate, and the other is located in the semiconductor substrate, the conductive semiconductor structure 13 further includes a third conductive semiconductor portion 21 electrically contacting the first conductive semiconductor portion 17. The third conductive semiconductor portion 21 is disposed above a portion of the doped semiconductor layer away from the semiconductor substrate.

[0157] The third type, such as Fig.63 As shown, when the first doping region 11 and the second doping region 12 both include a doped semiconductor layer located on the backlight surface of the semiconductor substrate, the conductive semiconductor structure includes the first conductive semiconductor portion and the second conductive semiconductor portion.

[0158] The fourth type, such as Fig.65 As shown, when the first doping region 11 and the second doping region 12 are both formed in the semiconductor substrate, the conductive semiconductor structure 13 further includes a third conductive semiconductor portion 21 electrically contacting the first conductive semiconductor portion 17. The second conductive semiconductor portion 18 is disposed above a portion of one of the first doping region 11 and the second doping region 12 away from the semiconductor substrate, and the third conductive semiconductor portion 21 is disposed above a portion of the other of the first doping region 11 and the second doping region 12 away from the semiconductor substrate.

[0159] In terms of the surface height difference, along the thickness direction of the semiconductor substrate, the ratio of the height from the upper surface of the second conductive semiconductor portion to the upper surface of the first doping region or the second doping region disposed directly below it to the thickness of the first doping region or the second doping region disposed directly below the same second conductive semiconductor portion can be greater than or equal to 0.5 and less than or equal to 1.5. In this case, it can be prevented that the thickness of the first doping region or the second doping region is smaller due to the larger ratio, resulting in poor field passivation capability corresponding to itself. In addition, it can also be prevented that the thickness of the first doping region or the second doping region is larger due to the smaller ratio, resulting in high parasitic absorption corresponding to itself, thereby ensuring that the back contact battery has a higher working efficiency.

[0160] Exemplarily, along the thickness direction of the semiconductor substrate, the height from the upper surface of the second conductive semiconductor portion to the upper surface of the first doping region or the second doping region disposed directly thereunder may be greater than or equal to 50 nm and less than or equal to 2 μm. For example, along the thickness direction of the semiconductor substrate, the height from the upper surface of the second conductive semiconductor portion to the upper surface of the first doping region or the second doping region disposed directly thereunder may be 50 nm, 100 nm, 300 nm, 600 nm, 900 nm, 1.2 μm, 1.5 μm, or 2 μm, etc.

[0161] In addition, when the first doped region, the second doped region and the conductive semiconductor structure all include the above-mentioned doped semiconductor layer, Fig.18 , Fig.19 , Fig.24 and Fig.34 As shown, the setting height of the surface of the region of the backlight surface corresponding to the conductive semiconductor structure 13 can be greater than or equal to the setting height of the surface of the region of the backlight surface corresponding to the first doping region 11 (or the second doping region 12) of the opposite conductivity type to the conductive semiconductor structure 13. Or, as Fig. 20 , Fig.25 and Fig.36As shown, the setting height of the surface of the region of the backlight surface corresponding to the conductive semiconductor structure 13 may also be less than the setting height of the surface of the region of the backlight surface corresponding to the first doping region 11 (or the second doping region 12) of the opposite conductivity type to the conductive semiconductor structure 13. In this case, in the actual manufacturing process, when the conductive semiconductor structure 13 is formed, the material used to manufacture the doped semiconductor layer included in the conductive semiconductor structure 13 is difficult to fill in the corner caused by the height difference, which easily leads to the doped semiconductor layer included in the conductive semiconductor structure 13 being difficult to completely contact with each part of the corresponding structure surface at the corner. Therefore, the setting height of the regional surface of the conductive semiconductor structure 13 corresponding to the backlight side can also be less than the setting height of the regional surface of the backlight side corresponding to the first doping region 11 (or the second doping region 12) of the opposite conductivity type to the conductive semiconductor structure 13. When the setting height of the regional surface of the backlight side corresponding to the conductive semiconductor structure 13 can be greater than or equal to the setting height of the regional surface of the backlight side corresponding to the first doping region 11 (or the second doping region 12) of the opposite conductivity type to the conductive semiconductor structure 13, the part of the doped semiconductor layer filled at the corner by the conductive semiconductor structure 13 can be staggered with the side wall of the doped semiconductor layer included in the first doping region 11 of the opposite conductivity type (or the doped semiconductor layer included in the second doping region 12), so as to ensure that the conductive semiconductor structure 13 has a larger lateral effective electrical contact area with the first doping region 11 (or the second doping region 12) of the opposite conductivity type.

[0162] Specifically, when the height of the doped semiconductor layer included in the conductive semiconductor structure on the backlight side is less than the height of the doped semiconductor layer included in the first doped region (or the doped semiconductor layer included in the second doped region) of opposite conductivity type to itself on the backlight side, the height difference can be determined according to the manufacturing process of the conductive semiconductor structure in the actual application scenario. Exemplarily, the difference between the height of the surface of the doped semiconductor layer included in the region corresponding to the conductive semiconductor structure on the backlight side and the height of the doped semiconductor layer included in the region corresponding to the first doped region and the second doped region of the backlight side and opposite conductivity type to the conductive semiconductor structure can be greater than or equal to -2μm and less than or equal to -0.4μm. For example, the height difference can be -2μm, -1.8μm, -1.5μm, -1.2μm, -1μm, -0.8μm or -0.4μm, etc.

[0163] As for the type of the physical spacing layer formed on the first doping region and the second doping region, it can be determined according to the conductive properties of the physical spacing layer and the actual application scenario. Exemplarily, the physical spacing layer may include a transparent conductive layer to enhance the transmission efficiency of carriers. Alternatively, the physical spacing layer may include a surface passivation layer of a material such as silicon nitride, aluminum oxide or titanium oxide to passivate the surface defects of the first doping region and the second doping region away from the semiconductor substrate. Alternatively, the physical spacing layer may include a doped silicon glass layer (the doped silicon glass layer may be a phosphorus silicon glass layer or a borosilicate glass layer, etc.) formed when the first doping region and / or the second doping region of the silicon material are doped by a diffusion process. The doped silicon glass layer may be a conductive layer or an insulating layer. Specifically, when the thickness of the doped silicon glass layer is large, the doped silicon glass layer may be an insulating layer; when the thickness of the doped silicon glass layer is small, the doped silicon glass layer may be a conductive layer with a certain conductivity. In this application, a doped silicon glass layer with a certain conductivity is referred to as a conductive doped silicon glass layer, and the doped silicon glass layer is defaulted to an insulating doped silicon glass layer.

[0164] In actual application, the height of the side effective electrical contact surface is defined as the side effective electrical contact height Z. The following is described in at least two cases according to the different formation positions of the first doping region and the second doping region on the backlight side:

[0165] The first one, such as Fig.64 and Fig.66 As shown, the first doping region 11, the second doping region 12 and at least part of the conductive semiconductor structure 13 are all formed in the semiconductor substrate, and the surface of each of the first doping region 11, the second doping region 12 and the conductive semiconductor structure 13 facing away from the light-facing surface of the semiconductor substrate is flush with the surface of the corresponding area of ​​the backlight surface of the semiconductor substrate. In the above case, the contact surface between the one of the first doping region 11 and the second doping region 12 with the opposite conductivity type to the conductive semiconductor structure and the conductive semiconductor structure 13 includes a lateral effective electrical contact surface; the height of the lateral effective electrical contact surface is the lateral effective electrical contact height Z, and the lateral effective electrical contact height Z is equal to the minimum value of the first depth and the second depth; the first depth is the depth of the one of the first doping region 11 and the second doping region 12 with the opposite conductivity type to the conductive semiconductor structure 13, and the second depth is the depth of the portion of the conductive semiconductor structure 13 in the semiconductor substrate. For example, when the depth of one of the first doped region 11 and the second doped region 12 having a conductivity type opposite to that of the conductive semiconductor structure 13 is the depth H1 of the first doped region 11 , and the depth H of the conductive semiconductor structure 13 is greater than H1 , the above-mentioned side effective electrical contact height Z is equal to H1 .

[0166] The second type, the one of the first doping region and the second doping region having the opposite conductivity type to the conductive semiconductor structure, and the conductive semiconductor structure both include a doped semiconductor layer formed on the backlight surface of the semiconductor substrate; the contact surface between the one of the first doping region and the second doping region having the opposite conductivity type to the conductive semiconductor structure and the conductive semiconductor structure includes a side effective electrical contact surface; the height of the side effective electrical contact surface is the side effective electrical contact height Z. The side effective electrical contact height Z is equal to the minimum value of the first thickness and the second thickness; along the extension direction of the side effective electrical contact surface, the first thickness is the thickness of the side effective electrical contact surface corresponding to the one of the first doping region and the second doping region having the opposite conductivity type to the conductive semiconductor structure, and the second thickness is the thickness of the side effective electrical contact surface corresponding to the conductive semiconductor structure. For example: along the extension direction of the side effective electrical contact surface, when the thickness of the side effective electrical contact surface corresponding to the one of the first doping region and the second doping region having the opposite conductivity type to the conductive semiconductor structure is the thickness H2 of the second doping region, and the thickness H of the conductive semiconductor structure is greater than H2, the above side effective electrical contact height Z is equal to H2.

[0167] Specifically, in the second case above, when the first doped region, the second doped region and the conductive semiconductor structure all include a doped semiconductor layer formed on the backlight surface, the above-mentioned side effective electrical contact height Z and the effective electrical contact area corresponding to the conductive semiconductor structure can be described in combination with the relationship between the conductive semiconductor structure and the conductivity type of the first doped region and the second doped region, the setting height of the doped semiconductor layer included in the first doped region and the second doped region on the semiconductor substrate, and the formation of the conductive semiconductor structure:

[0168] The first type is that the conductive semiconductor structure is continuous with the first doping region, and the conductive semiconductor structure and the second doping region have opposite conductivity types. In the above case, when the conductive semiconductor structure is only located between the first doping region and the second doping region, Fig.15 As shown, if the semiconductor substrate is a plane, the effective electrical contact area corresponding to the conductive semiconductor structure is H2×W, and the effective electrical contact height Z of the side is H2, where H2 is the thickness of the second doped region. Fig.16 As shown, if the height of the doped semiconductor layer included in the first doped region and the conductive semiconductor structure on the semiconductor substrate is greater than the height of the second doped region, the effective electrical contact area corresponding to the conductive semiconductor structure is H×W, and the side effective electrical contact height Z is H, where H is the thickness of the conductive semiconductor structure. Fig.17As shown, if the setting height of the doped semiconductor layer included in the first doped region and the conductive semiconductor structure on the semiconductor substrate is less than the setting height of the doped semiconductor layer included in the second doped region, the corresponding effective electrical contact area of ​​the conductive semiconductor structure is H2×W, and the side effective electrical contact height Z is H2, where H is the thickness of the conductive semiconductor structure.

[0169] In the first case, when the conductive semiconductor structure includes the first conductive semiconductor portion and the second conductive semiconductor portion, as Figures 18 to 20 As shown, regardless of whether the doped semiconductor layers included in the first doped region and the second doped region are arranged at the same height on the semiconductor substrate, if the arrangement corresponding to the second conductive semiconductor portion 18 is an electrical arrangement, the effective electrical contact area corresponding to the conductive semiconductor structure is H2×W+W×X, and the effective electrical contact height Z on the side is H2; if the arrangement corresponding to the second conductive semiconductor portion 18 is an electrical arrangement, the effective electrical contact area corresponding to the conductive semiconductor structure is H2×W, and the effective electrical contact height Z on the side is H2. Wherein, the above X is one of the above X1, X2 or X3.

[0170] The second type is that the conductive semiconductor structure is continuous with the second doping region. In this case, the conductive semiconductor structure has an opposite conductivity type to the first doping region. In the above case, when the conductive semiconductor structure is only located between the first doping region and the second doping region, Fig.21 As shown, if the semiconductor substrate is a plane, the effective electrical contact area corresponding to the conductive semiconductor structure is H2×W, and the side effective electrical contact height Z is H1, where H1 is the thickness of the first doped region. Fig.23 As shown, if the height of the doped semiconductor layer included in the second doped region and the conductive semiconductor structure on the semiconductor substrate is less than the height of the doped semiconductor layer included in the first doped region, the effective electrical contact area corresponding to the conductive semiconductor structure is H1×W, and the side effective electrical contact height Z is H1. Fig. 22 As shown, if the setting height of the doped semiconductor layer included in the second doped region and the conductive semiconductor structure on the semiconductor substrate is greater than the setting height of the doped semiconductor layer included in the first doped region, the effective electrical contact area corresponding to the conductive semiconductor structure is H×W, and the side effective electrical contact height Z is H.

[0171] In the second case, when the conductive semiconductor structure includes the first conductive semiconductor portion and the second conductive semiconductor portion, as Figure 24 to Figure 26As shown, regardless of whether the doped semiconductor layers included in the first doped region and the second doped region are arranged at the same height on the semiconductor substrate, if the corresponding arrangement mode of the second conductive semiconductor portion 18 is an electrical arrangement, then the effective electrical contact area corresponding to the conductive semiconductor structure is H1×W+W×X, and the side effective electrical contact height Z is H1; if the corresponding arrangement mode of the second conductive semiconductor portion 18 is an electrical arrangement, then the effective electrical contact area corresponding to the conductive semiconductor structure is H1×W, and the side effective electrical contact height Z is H1.

[0172] The third type is that the conductive semiconductor structure is not integrally continuous with the first doping region and the second doping region, and the conductive semiconductor structure has an opposite conductivity type to the first doping region. Fig.33 As shown, if the heights of the doped semiconductor layers included in the second doped region and the conductive semiconductor structure on the semiconductor substrate are both greater than the height of the doped semiconductor layers included in the first doped region, the effective electrical contact area corresponding to the conductive semiconductor structure is H×W, and the side effective electrical contact height Z is H. Figures 27 to 32 ,as well as Figure 34 to Figure 39 As shown, the effective electrical contact area corresponding to the conductive semiconductor structure under the remaining distribution is H1×W, and the side effective electrical contact height Z is H1.

[0173] Fourth, the conductive semiconductor structure is not integrally continuous with the first doping region and the second doping region, and the conductive semiconductor structure and the second doping region have opposite conductivity types. Fig.43 and Fig.44 As shown, if the heights of the doped semiconductor layers included in the first doped region and the conductive semiconductor structure on the semiconductor substrate are both greater than the height of the doped semiconductor layers included in the second doped region, the effective electrical contact area corresponding to the conductive semiconductor structure is H×W, and the side effective electrical contact height Z is H. Figure 40 to Figure 42 ,as well as Figures 45 to 49 As shown, the effective electrical contact area corresponding to the conductive semiconductor structure under the remaining distribution is H2×W, and the side effective electrical contact height Z is H2.

[0174] It is worth noting that, from the first to fourth cases, it can be seen that the effective electrical contact height of the side surface of the first doped region and the second doped region electrically coupled through the conductive semiconductor structure is Z. Fig.15 , Fig.18 , Fig.21 , Figure 27 to Figure 29 , Fig.34 and Fig.35 ,as well as Fig.40 and Fig.42As shown, when the backlight surface of the semiconductor substrate is a plane, the effective electrical contact height Z of the side surface is equal to the thickness of the first doping region 11 and the second doping region 12 that is opposite to the conductive type of the conductive semiconductor structure 13 (ie, H1 or H2).

[0175] or, as Fig.16 , Fig.23 , Fig.33 , Fig.43 and Fig.44 As shown, in the case where the setting height of the doped semiconductor layer included in the one of the first doping region 11 and the second doping region 12 with the conductivity type opposite to the conductive semiconductor structure 13 on the side of the semiconductor substrate backlight surface is less than the setting height of the doped semiconductor layer included in the conductive semiconductor structure 13 on the side of the semiconductor substrate backlight surface, and a part of the side surface of the doped semiconductor layer included in the one of the first doping region 11 and the second doping region 12 with the conductivity type opposite to the conductive semiconductor structure 13 is in electrical contact with the semiconductor substrate, and a part of the side surface of the doped semiconductor layer included in the one of the first doping region 11 and the second doping region 12 with the conductivity type opposite to the conductive semiconductor structure 13 is in electrical contact with the conductive semiconductor structure 13, the side effective electrical contact height Z is equal to the thickness of the conductive semiconductor structure 13 (i.e., H);

[0176] or, as Fig.17 , Fig.19 , Fig. 20 , Fig. 22 , Figure 24 to Figure 26 , Figure 30 to Figure 32 , Figure 37 to Figure 39 As shown, when the doped semiconductor layers included in the first doping region 11 and the second doping region 12 are arranged at different heights on the backlight side of the semiconductor substrate, and the partial regions corresponding to the conductive semiconductor structure in the side surface of the doped semiconductor layer included in the one of the first doping region 11 and the second doping region 12 with a conductivity type opposite to that of the conductive semiconductor structure 13 are all in electrical contact with the conductive semiconductor structure, the side effective electrical contact height Z is equal to the thickness of the one of the first doping region 11 and the second doping region 12 with a conductivity type opposite to that of the conductive semiconductor structure 13.

[0177] In addition, it can be known from the above content that the setting height of the doped semiconductor layer included in the one of the first doping region and the second doping region with the opposite conductivity type of the conductive semiconductor structure near the backlight side of the semiconductor substrate is less than the setting height of the doped semiconductor layer included in the conductive semiconductor structure near the backlight side of the semiconductor substrate, and a part of the side of the doped semiconductor layer included in the first doping region and the second doping region with the opposite conductivity type of the conductive semiconductor structure is in electrical contact with the semiconductor substrate, and another part of the side of the doped semiconductor layer included in the first doping region and the second doping region with the opposite conductivity type of the conductive semiconductor structure is in electrical contact with the conductive semiconductor structure, part of the side of the doped semiconductor layer included in the first doping region and the second doping region with the opposite conductivity type of the conductive semiconductor structure is in electrical contact with the semiconductor substrate, so that only part of the side of the doped semiconductor layer included in the first doping region and the second doping region near the conductive semiconductor structure is in electrical contact with the conductive semiconductor structure. In this case, the difference range between the height of the surface of the region of the backlight side corresponding to the conductive semiconductor structure and the height of the surface of the region of the backlight side corresponding to the first doping region and the second doping region with the opposite conductivity type of the conductive semiconductor structure can be determined according to the process of manufacturing the first doping region and the second doping region in the actual application scenario. Exemplarily, in this case, along the thickness direction of the semiconductor substrate, in the backlight surface, the difference between the height of the surface of the region corresponding to the conductive semiconductor structure and the height of the surface of the region corresponding to the doped semiconductor layer included in the first doping region and the second doping region of the conductive semiconductor structure of the opposite conductivity type can be greater than or equal to 0.4μm and less than or equal to 2μm. For example: in this case, the difference between the height of the surface of the region corresponding to the conductive semiconductor structure on the backlight surface and the height of the surface of the region corresponding to the first doping region and the second doping region of the conductive semiconductor structure of the opposite conductivity type can be 0.4μm, 0.6μm, 0.8μm, 1μm, 1.5μm, 1.8μm or 2μm, etc. In this case, the first doping region is opposite to the conductive semiconductor structure as an example for explanation: when forming the doped semiconductor layer included in the first doping region, the material for manufacturing the doped semiconductor layer included in the first doping region is difficult to fill in the corner caused by the height difference, which easily leads to the doped semiconductor layer included in the first doping region being difficult to fully contact with each part of the surface of the semiconductor substrate (or, the semiconductor substrate and the conductive semiconductor structure) at the corner. Therefore, if the difference between the height of the surface of the area corresponding to the conductive semiconductor structure on the backlight side and the height of the surface of the area corresponding to one of the first doping region and the second doping region of the backlight side having a conductivity type opposite to that of the conductive semiconductor structure is within the above range, the part of the doped semiconductor layer filled in the first doping region at the corner can be staggered with the side wall of the conductive semiconductor structure of the opposite conductivity type to itself, thereby ensuring a larger lateral effective electrical contact area between the conductive semiconductor structure and the first doping region of the opposite conductivity type to itself.When the conductivity type of the second doped region is opposite to that of the conductive semiconductor structure, the corresponding beneficial effects are the same as the above effects, which will not be described in detail here.

[0178] As for the effective electrical contact surface corresponding to each conductive semiconductor structure, it includes a side effective electrical contact surface and / or a top effective electrical contact surface. Specifically, the above effective electrical contact area S is equal to α×W×X+β×Z×W. Among them, α and β are both greater than or equal to 0 and less than or equal to 1. Among them, the specific sizes of α and β can be determined according to the formation position of the conductive semiconductor structure, the conductive properties of the above physical spacing layer, and the specific structure of the back contact battery.

[0179] For example, if the conductive semiconductor structure does not include a second conductive semiconductor portion disposed above the first doped region and / or the second doped region away from the semiconductor substrate, or the second conductive semiconductor portion included in the conductive semiconductor structure is disposed in an insulating manner, then α is equal to 0. In this case, β is greater than 0 and less than or equal to 1, and the effective electrical contact area is equal to β×Z×W.

[0180] For example: if the first doped region and the second doped region are both formed in the semiconductor substrate, and the conductive semiconductor structure is only formed on the semiconductor substrate, or the one of the first doped region and the second doped region with the opposite conductivity type to the conductive semiconductor structure is located in the semiconductor substrate, and the conductive semiconductor structure is only arranged above the part of the first doped region and the second doped region with the opposite conductivity type to the conductive semiconductor structure away from the semiconductor substrate, then β is equal to 0. The effective electrical contact area is the effective electrical contact area of ​​the top surface. Secondly, in this case, α is greater than 0 and less than or equal to 1. The effective electrical contact area is equal to α×W×X.

[0181] For example, if the configuration corresponding to the second conductive semiconductor portion included in the conductive semiconductor structure is an electrical configuration, and the effective electrical contact surface between the first doped region and the second doped region having the opposite conductivity type to the conductive semiconductor structure and the conductive semiconductor structure also includes a side effective electrical contact surface, then α is greater than 0 and less than or equal to 1, and β is greater than or equal to 0 and less than or equal to 1. It can be understood that the effective electrical contact area S is equal to α×W×X+β×Z×W.

[0182] Among them, when α is greater than 0, the specific size of α can be determined according to the electrical conductivity of the top effective electrical contact surface between the second conductive semiconductor portion and the one with the opposite conductivity type to the conductive semiconductor structure in the first doping region and the second doping region. For example: when the second conductive semiconductor portion is directly formed above the portion of the one with the opposite conductivity type to the conductive semiconductor structure in the first doping region and the second doping region that is away from the semiconductor substrate, α can be equal to 1. Alternatively, when a physical spacing layer with good conductive properties such as a transparent conductive layer is formed between the second conductive semiconductor portion and the one with the opposite conductivity type to the conductive semiconductor structure in the first doping region and the second doping region, α can also be equal to 1. Alternatively, when a physical spacing layer with poor conductive properties such as a conductive doped silicon glass layer is formed between the second conductive semiconductor portion and the one with the opposite conductivity type to the conductive semiconductor structure in the first doping region and the second doping region, α can also be less than 1.

[0183] When β is greater than 0, the specific value of β can be determined according to the electrical conduction between the conductive semiconductor structure and the side of the conductive semiconductor structure in the first doping region and the second doping region. For example, when the conductive semiconductor structure, the first doping region and the second doping region all include the above-mentioned doped semiconductor layer, and the doped semiconductor layer included in the conductive semiconductor structure and the side of the doped semiconductor layer included in the first doping region and the second doping region with the opposite conductivity type of the conductive semiconductor structure are in direct contact, β can be equal to 1. In addition, the above β can be greater than or equal to α.

[0184] In the above case, the electrical contact area can be regulated by adjusting the sizes of α and β to obtain a suitable effective electrical contact surface area and achieve optimal design of product configuration.

[0185] Secondly, in the actual application process, the orthographic projection area of ​​the conductive semiconductor structure on the backlight side may affect the effective electrical contact area corresponding to the conductive semiconductor structure, thereby affecting the leakage current formed by the first doping region and the second doping region through the conductive semiconductor structure, and further affecting the reverse breakdown voltage of the back contact battery and the working efficiency of the back contact battery under normal working conditions. Based on this, the ratio between the orthographic projection area of ​​each conductive semiconductor structure on the backlight side and the area of ​​the backlight surface, as well as the range of the conductive semiconductor structure set on the first doping region and / or the second doping region can be determined according to the requirements for the reverse breakdown voltage and working efficiency of the back contact battery in the actual application scenario, and the accuracy of the manufacturing equipment for actually manufacturing the back contact battery.

[0186] For example, the orthographic projection area of ​​the portion of the at least one conductive semiconductor structure located between the first doping region and the second doping region on the backlight side is S1, the area of ​​the backlight side is S2, and the ratio of S1 to S2 may be greater than or equal to 8.5×10-7 %, and less than or equal to 6.67×10 -1 % For example, the ratio between the orthographic projection area of ​​at least one conductive semiconductor structure on the backlight side and the area of ​​the backlight side may be 8.5×10 -7 %, 1×10 -6 %, 1×10 -5 %, 1×10 -4 %, 1×10 -3 %, 1×10 -2 %, 1×10 -1 % or 6.67×10 -1 %. In this case, it is possible to prevent the magnitude of the reverse breakdown voltage of the back contact battery that can be reduced by setting a conductive semiconductor structure due to a small S1, prevent the back contact battery from being burned due to local heat concentration, and effectively reduce the risk of hot spots in the photovoltaic module including the back contact battery provided by the embodiment of the present invention; it is also possible to prevent strict requirements on etching accuracy in order to form a smaller conductive semiconductor structure, thereby reducing the difficulty of etching. In addition, it is also possible to prevent the leakage current of the back contact battery under normal working conditions from being large due to a large S1, further ensuring that the photovoltaic module including the back contact battery provided by the embodiment of the present invention has a higher photoelectric conversion efficiency in the forward voltage region.

[0187] The specific value of the orthographic projection area of ​​the portion of each conductive semiconductor structure located between the first doping region and the second doping region on the backlight side can be determined according to the above ratio and the specific size of the semiconductor substrate used in the actual application scenario. For example, when the area of ​​the backlight side of the semiconductor substrate is 359.0364 square centimeters, the orthographic projection area of ​​the portion of at least one conductive semiconductor structure located between the first doping region and the second doping region on the backlight side can be any value greater than or equal to 300 square microns and less than or equal to 2.4 square centimeters.

[0188] Preferably, the ratio between S1 and S2 can be greater than or equal to 7.2×10 -6 %, and less than or equal to 4.6×10 -3 %. For example, the ratio between S1 and S2 can be 7.2×10 -6 %, 1×10 -5 %, 1×10 -4 %, 1×10 -3 % or 4.6×10 -3%. As for the preferred range of the orthographic projection area of ​​the portion of the conductive semiconductor structure located between the first doping region and the second doping region on the backlight side, it can be determined according to the above ratio and the specific size of the semiconductor substrate used in the actual application scenario. For example: when the area of ​​the backlight side of the semiconductor substrate is 34944 square millimeters, the orthographic projection area of ​​the portion of at least one conductive semiconductor structure located between the first doping region and the second doping region on the backlight side can be any value greater than or equal to 0.0025 square millimeters and less than or equal to 1.6 square millimeters. In this case, the ratio between S1 and S2 has a large optional range, and a suitable solution can be selected according to the requirements of the version of the back contact battery in the actual application scenario, leakage prevention, and reduction of hot spot risks, etc., which is conducive to improving the applicability of the back contact battery provided by the present invention in different application scenarios. In addition, it is also possible to prevent the effective electrical contact area corresponding to a single conductive semiconductor structure from being too small or too large. This effect can be referred to the previous text and will not be repeated here.

[0189] In the case where the conductive semiconductor structure includes the above-mentioned first conductive semiconductor portion and the second conductive semiconductor portion, the area ratio of the orthographic projection area S4 of the second conductive semiconductor portion on the backlight side can be determined based on the requirements for the reverse breakdown voltage and working efficiency of the back-contact battery in the actual application scenario, as well as the accuracy of the manufacturing equipment for actually manufacturing the back-contact battery, and is not specifically limited here.

[0190] For example, the ratio of S4 to S2 may be greater than 0 and less than or equal to 4.6×10 -3 %. For example, the ratio between S4 and S2 can be 0.1×10 -3 %、0.5×10 -3 %、1.0×10 -3 %、1.5×10 -3 %, 2×10 -3 %, 2.5×10 -3 %, 3×10 -3 %, 4×10 -3 % or 4.6×10 -3%. As for the preferred range of the orthographic projection area of ​​the second conductive semiconductor portion on the backlight side, it can be determined according to the above ratio and the specific size of the semiconductor substrate used in the actual application scenario. For example: when the area of ​​the backlight side of the semiconductor substrate is 34944 square millimeters, the orthographic projection area of ​​the second conductive semiconductor portion on the backlight side can be any value greater than 0 and less than or equal to 1.6 square millimeters. In this case, it can be prevented that the larger ratio between S4 and S2 makes the second conductive semiconductor portion larger in the first doping region and / or the second doping region, thereby affecting the formation of the electrode structure. While reducing the difficulty of manufacturing the electrode structure, it can also ensure that the electrode structure has good contact performance with the corresponding doping region, and the electrode structure itself has good transmission performance.

[0191] As for the specific size of the effective electrical contact area corresponding to each conductive semiconductor structure, it can be determined based on the formation range of the conductive semiconductor structure, the requirements for the reverse breakdown voltage and working efficiency of the back contact battery in the actual application scenario, the format size requirements for the back contact battery in the actual application scenario, and the accuracy of the manufacturing equipment for actually manufacturing the back contact battery.

[0192] Wherein, in the case where the conductive semiconductor structure includes the second conductive semiconductor portion, according to different configurations of the conductive semiconductor structure, the specific size of the effective electrical contact area is divided into the following two cases for description:

[0193] For example, when the conductive semiconductor structure is insulated and disposed on a portion of the first doping region and / or the second doping region that is in electrical contact with itself, the effective electrical contact area corresponding to at least one conductive semiconductor structure may be greater than or equal to 0.000025 mm 2 , and less than or equal to 0.016mm 2 For example, in this case, the effective electrical contact area corresponding to at least one conductive semiconductor structure may be 0.000025 mm 2 、0.0001mm 2 、0.0012mm 2 、0.0015mm 2 、0.0018mm 2 、0.002mm 2 、0.0022mm 2 , 0.0025mm 2 、0.005mm 2 , 0.01mm 2 or 0.016mm 2Etc. In this case, if the effective electrical contact area corresponding to at least one conductive semiconductor structure is within the above range, it can prevent the magnitude of the reverse breakdown voltage of the back contact battery that can be reduced by setting the conductive semiconductor structure from being low due to the small effective electrical contact area corresponding to the conductive semiconductor structure, prevent the back contact battery from being burned due to local heat concentration, and effectively reduce the risk of hot spots in the photovoltaic module including the back contact battery provided by the embodiment of the present invention; it can also prevent the strict requirements on etching accuracy for forming a smaller conductive semiconductor structure, thereby reducing the difficulty of etching. In addition, it can also prevent the leakage current of the back contact battery under normal working conditions from being large due to the large effective electrical contact area corresponding to the conductive semiconductor structure, further ensuring that the photovoltaic module including the back contact battery provided by the embodiment of the present invention has a high photoelectric conversion efficiency in the forward voltage region; it can also prevent the size range of the back contact battery provided by the embodiment of the present invention from being limited due to the W and / or Z values ​​being larger in order to increase the effective electrical contact area corresponding to the conductive semiconductor structure, further expanding the scope of application of the back contact battery provided by the embodiment of the present invention.

[0194] For example, when the configuration mode of the conductive semiconductor structure is an electrical configuration, the effective electrical contact area corresponding to at least one conductive semiconductor structure may be greater than or equal to 0.000175 mm 2 , and less than or equal to 1.616mm 2 For example, in this case, the effective electrical contact area corresponding to at least one conductive semiconductor structure may be 0.000175 mm 2 、0.001mm 2 、0.005mm 2 , 0.01mm 2 , 0.02mm 2 , 0.04mm 2 , 0.06mm 2 、0.08mm 2 , 0.1mm 2 , 0.2mm 2 , 0.6mm 2 , 1mm 2 , 1.2mm 2 or 1.616mm 2 , etc. The beneficial effect in this case is similar to that in the case where the conductive semiconductor structure is insulated and arranged on the portion of the first doping region and / or the second doping region that is in electrical contact with itself, and the effective electrical contact area corresponding to at least one conductive semiconductor structure is greater than or equal to 0.000025 mm 2 , and less than or equal to 0.016mm 2 The beneficial effects are similar and will not be repeated here.

[0195] When the conductive semiconductor structure is only located between the first doping region and the second doping region, only the sidewalls of the conductive semiconductor structure are in contact with the first doping region and the second doping region, respectively. At this time, the effective electrical contact area corresponding to the conductive semiconductor structure can refer to the effective electrical contact area corresponding to the portion of the conductive semiconductor structure that is insulated and arranged in the first doping region and / or the second doping region and is in electrical contact with itself as described above, which will not be repeated here.

[0196] As for the specific size of each conductive semiconductor structure, it can be determined according to the specific formation position of the portion of each conductive semiconductor structure between the first doping region and the second doping region, the range of the conductive semiconductor structure on the first doping region and / or the second doping region, and the actual application scenario, as long as 0.5D1≤W≤6D1 is satisfied. Specifically, W can be any value greater than or equal to 0.5D1 and less than or equal to 6D1. For example, the value of W can be equal to 0.5D1, D1, 2D1, 3D1, 4D1, 5D1 or 6D1, etc.

[0197] Preferably, W can be any value greater than or equal to 0.5D1 and less than or equal to 3D1. For example, the value of W can be equal to 0.5D1, 0.8D1, D1, 1.5D1, 2D1, 2.5D1 or 3D1, etc. In this case, in the actual application process, not only the width of the conductive semiconductor structure along the extension direction of the spacing region will affect the effective electrical contact area between the conductive semiconductor structure and the first doping region and the second doping region, but also the thickness of the conductive semiconductor structure (and, in the case where the corresponding arrangement of the conductive semiconductor structure is to be electrically arranged on the part of the first doping region and / or the second doping region that is in electrical contact with itself, the width of the part of the conductive semiconductor structure arranged on the first doping region and / or the second doping region; or the doping concentration of impurities in the conductive semiconductor structure, etc.) may also affect the size of the above-mentioned effective electrical contact area. For example: when the doped semiconductor layers included in the first doped region and the second doped region have different setting heights on the semiconductor substrate, and the one with the smaller setting height is smaller than the setting height of the doped semiconductor layer included in the conductive semiconductor structure on the semiconductor substrate, and the one with the smaller setting height is opposite to the conductive type of the conductive semiconductor structure, the greater the thickness of the doped semiconductor layer included in the conductive semiconductor structure, the greater the above-mentioned effective electrical contact area. In the above case, the width W of the above-mentioned conductive semiconductor structure along the extension direction of the spacing region is within the above-mentioned range, and a predetermined setting space can be reserved at least for the thickness range of the conductive semiconductor structure and / or the setting width range under the electrical setting, so as to prevent the above-mentioned effective electrical contact area from being larger due to the thickness, width W and setting width of the conductive semiconductor structure being larger, thereby ensuring that the back contact battery has a relatively high working efficiency.

[0198] As for the width of the conductive semiconductor structure, it can be determined according to the orthographic projection area of ​​the conductive semiconductor structure on the backlight side and the range in which the conductive semiconductor structure is disposed on the first doping region and / or the second doping region.

[0199] Exemplarily, the width of the spacing region between the first doping region 11 and the second doping region 12 is D1. Along the extension direction of the spacing region, the width of the conductive semiconductor structure 13 is W, and 0.5D1≤W≤6D1. In this case, the effective electrical contact area between the conductive semiconductor structure 13 and the first doping region and the second doping region, and the area ratio of the effective contact part of the conductive semiconductor structure 13 with the first doping region and the second doping region on the backlight side can be effectively adjusted by adjusting the value of W, so as to prevent the magnitude of the reverse breakdown voltage of the back contact battery that can be reduced by setting the conductive semiconductor structure 13 from being low due to the small total effective electrical contact area between a single conductive semiconductor structure 13 and the first doping region and the second doping region, and the area ratio of the effective contact part of all conductive semiconductor structures 13 with the first doping region and the second doping region on the backlight side, and prevent the back contact battery from being burned due to local heat concentration. Within a certain range, the smaller conductive semiconductor structure 13 has higher requirements for etching accuracy, so W≥0.5D1 can further reduce the manufacturing difficulty of forming the conductive semiconductor structure 13 on the backlight side. In addition, each conductive semiconductor structure 13 can be regarded as a local recombination center disposed between the first doping region and the second doping region. Based on this, when W is within the above range, it is also possible to prevent a large local leakage current between the first doping region and the second doping region due to a large value of W, thereby ensuring that the photovoltaic module including the back contact cell provided by the embodiment of the present invention has a high photoelectric conversion efficiency in the forward voltage region.

[0200] For example, Figure 3 As shown, in some cases, the above-mentioned back contact battery may also include at least one conductive semiconductor structure 13 at least partially located between two adjacent strip-shaped doped regions 14 of opposite conductivity types. In this case, the width of the strip-shaped doped region 14 in contact with the conductive semiconductor structure 13 in the first doped region is defined as D2; the width of the strip-shaped doped region 14 in contact with the conductive semiconductor structure 13 in the second doped region is defined as D3; along the distribution direction of the strip-shaped doped regions 14 of opposite conductivity types, the length of the conductive semiconductor structure 13 is D, and D1≤D≤D1+D2+D3. In this case, as Figure 3As shown, after the format of the back-contact battery is determined, the above-mentioned D1, D2 and D3 are fixed values. Based on this, in the case where the conductive semiconductor structure 13 is at least partially located between two adjacent strip-shaped doping regions 14 of opposite conductivity types, if D is equal to D1, the conductive semiconductor structure 13 located between two adjacent strip-shaped doping regions 14 of opposite conductivity types can be electrically contacted with the two adjacent strip-shaped doping regions 14 of opposite conductivity types along the arrangement direction of the strip-shaped doping regions 14 of opposite conductivity types, respectively, to ensure that the first doping region 11 and the second doping region can be electrically connected through the conductive semiconductor structure 13; at the same time, the orthographic projection area of ​​the conductive semiconductor structure 13 on the backlight side can also be precisely controlled to ensure that the hot spot risk corresponding to the back-contact battery and the working efficiency under normal operation can accurately meet the working requirements. Secondly, as Figures 7 to 9 As shown, the D value can also be greater than D1, and less than or equal to D1+D2+D3. In this case, the conductive semiconductor structure 13 can not only be located between two adjacent strip-shaped doping regions 14 of opposite conductivity types, but can also be set on at least one of the two adjacent strip-shaped doping regions 14 of opposite conductivity types, which can prevent the strict requirement of etching accuracy in order to obtain only the conductive semiconductor structure 13 located only between the two adjacent strip-shaped doping regions 14 of opposite conductivity types, thereby reducing the difficulty of etching. Furthermore, in the case where the conductive semiconductor structure 13 is electrically set on the portion in the first doping region and / or the second doping region that is in electrical contact with itself, the size of the above-mentioned effective electrical contact area can be adjusted by adjusting the D value, which is conducive to achieving a balance between the reverse breakdown voltage and leakage loss of the back contact battery, and further conducive to making the back contact battery have good working performance.

[0201] Preferably, the above D value can satisfy In this case, the carriers collected by the first doping region and the second doping region need to be led out through the electrode structure that is in ohmic contact with itself. Based on this, along the width direction of the strip doping region, the first doping region and the second doping region include a portion of the strip doping region along the direction of its own extension that needs to be directly in ohmic contact with the electrode structure, and the ohmic contact area will occupy a certain width. In this case, when When the conductive semiconductor structure is set, it is helpful to prevent the etching accuracy from being strictly required to form a conductive semiconductor structure with a smaller setting width due to the smaller setting width corresponding to the conductive semiconductor structure, thereby reducing the etching difficulty; at the same time, it can also prevent the conductive semiconductor structure from being set in an electrical setting, and the effective electrical contact area corresponding to the conductive semiconductor structure is also smaller due to the smaller setting width, thereby preventing the back contact battery from having a poor effect of reducing the risk of hot spots by setting a conductive semiconductor structure. In addition, it is also helpful to prevent the electrode structure from being unable to make ohmic contact with the strip-shaped doping region included in the first doping region and the second doping region due to the larger setting width of the conductive semiconductor structure, thereby ensuring that the current collected by the first doping region and the second doping region can be derived through the electrode structure, thereby facilitating the formation of photocurrent.

[0202] For example, Figure 4 As shown, when the conductive semiconductor structure 13 is at least partially located between a strip doping region 14 included in one of the first doping region and the second doping region and an adjacent connection region 15 included in the other, the width of the connection region 15 belonging to one of the first doping region and the second doping region and in contact with the conductive semiconductor structure 13 is defined as W1; the length of the strip doping region 14 belonging to the other of the first doping region and the second doping region and in contact with the conductive semiconductor structure 13 is W2. In addition, along the width direction of the spacing region, the length of the conductive semiconductor structure 13 is D, and D1≤D≤D1+W1+W2. In this case, after the version of the back contact battery is determined, the above D1, W1 and W2 are fixed values. Based on this, in the case where the conductive semiconductor structure 13 is at least partially located between a strip doping region 14 included in one of the first doping region and the second doping region and an adjacent connecting region 15 included in the other, when D is equal to D1, the conductive semiconductor structure 13 located between the strip doping region 14 and the connecting region 15 of opposite conductivity type and adjacent can be electrically contacted with the strip doping region 14 and the connecting region 15 of opposite conductivity type and adjacent along the arrangement direction of the first doping region and the second doping region, respectively, to ensure that the first doping region and the second doping region can be electrically connected through the conductive semiconductor structure 13; at the same time, the orthographic projection area of ​​the conductive semiconductor structure 13 on the backlight side can also be precisely controlled to ensure that the hot spot risk corresponding to the back contact battery and the working efficiency under normal operation can accurately meet the working requirements. Secondly, if Fig.10As shown, the D value can also be greater than D1 and less than or equal to W1+W2+D1. In this case, the conductive semiconductor structure 13 can not only be located between the strip-shaped doping region 14 and the connecting region 15 of opposite and adjacent conductivity types, but can also be arranged on at least one of the strip-shaped doping region 14 and the connecting region 15 of opposite and adjacent conductivity types, which can prevent the strict requirement of etching accuracy for obtaining only the conductive semiconductor structure 13 located only between the strip-shaped doping region 14 and the connecting region 15 of opposite and adjacent conductivity types, thereby reducing the etching difficulty. Furthermore, in the case where the conductive semiconductor structure 13 is electrically arranged on the portion in the first doping region and / or the second doping region that is in electrical contact with itself, the size of the above-mentioned effective electrical contact area can be adjusted by adjusting the D value, which is conducive to achieving a balance between the reverse breakdown voltage and leakage loss of the back contact battery, and further conducive to making the back contact battery have good working performance.

[0203] Preferably, In this case, the carriers collected by the first doping region and the second doping region need to be led out through the electrode structure that is in ohmic contact with itself. Based on this, along the extension direction of the strip doping region, the first doping region and the second doping region include a portion of the strip doping region along the extension direction thereof that needs to be in direct ohmic contact with the electrode structure, and the ohmic contact area will occupy a certain length. In this case, when When the conductive semiconductor structure is formed, it is helpful to prevent the etching accuracy from being strictly required to form a conductive semiconductor structure with a smaller setting width due to the smaller setting width corresponding to the conductive semiconductor structure above the portion of the first doping region and / or the second doping region away from the semiconductor substrate, thereby reducing the etching difficulty; at the same time, it can also prevent the conductive semiconductor structure from being formed with a smaller setting width, which makes the effective electrical contact area corresponding to the conductive semiconductor structure smaller, thereby reducing the effect of reducing the risk of hot spots by setting the conductive semiconductor structure in the back contact battery. In addition, it is also helpful to prevent the electrode structure from being unable to make ohmic contact with the strip-shaped doping region included in the first doping region and the second doping region due to the larger setting width of the conductive semiconductor structure, thereby ensuring that the current collected by the first doping region and the second doping region can be led out through the electrode structure, thereby forming a photocurrent.

[0204] As for the data values ​​of D and W corresponding to the conductive semiconductor structure, they can be determined by the format of the back contact battery in the actual application scenario and the above-mentioned size relationship, and are not specifically limited here.

[0205] Specifically, exemplarily, in the case where the second conductive semiconductor portion is disposed above the portion of the corresponding strip-shaped doped region away from the semiconductor substrate along the width direction of the strip-shaped doped region, the width of the second conductive semiconductor portion along the width direction of the strip-shaped doped region may be greater than or equal to one tenth of the width of the corresponding strip-shaped doped region and less than one half of the width of the corresponding strip-shaped doped region. In this case, the carriers collected by the first doped region need to be led out through an electrode structure in ohmic contact with itself. Based on this, along the width direction of the strip-shaped doped region, a portion of the strip-shaped doped region included in the first doped region along its own extension direction needs to be directly in ohmic contact with the electrode structure, and the ohmic contact area will occupy a certain width. In this case, when the setting width of the second conductive semiconductor part is greater than or equal to one tenth of the width of the corresponding strip-shaped doped region and less than one half of the width of the corresponding strip-shaped doped region, it can prevent the etching accuracy from being strictly required for forming the second conductive semiconductor part with a smaller setting width due to the smaller setting width X1 corresponding to the second conductive semiconductor part, thereby reducing the etching difficulty; at the same time, it can also prevent the setting width X1 from being smaller when the setting mode corresponding to the second conductive semiconductor part is an electrical setting, so that the effective electrical contact area corresponding to the conductive semiconductor structure is also smaller, thereby preventing the effect of reducing the risk of hot spots by setting the conductive semiconductor structure in the back contact battery from being poor. In addition, it can also prevent the electrode structure from being unable to make ohmic contact with the strip-shaped doped region included in the first doped region due to the larger setting width X1 of the second conductive semiconductor part, thereby ensuring that the current collected by the first doped region can be derived through the electrode structure, thereby facilitating the formation of photocurrent.

[0206] Secondly, when the first doping region and the second doping region are alternately distributed in an interdigitated manner, such as Figures 7 to 9 As shown, when the D value of the conductive semiconductor structure 13 is greater than D1; or, as Fig.10 As shown, when the W value is greater than D2+2D1 or the W value is greater than D3+2D1, the conductive semiconductor structure 13 is also arranged above the portion of the first doping region and / or the second doping region that is away from the semiconductor substrate. At this time, the size of the effective electrical contact area corresponding to the conductive semiconductor structure 13 may be affected. Therefore, the setting size of the conductive semiconductor structure 13, the ratio and specific size between the width W and the side effective electrical contact height Z can be determined according to the position where the conductive semiconductor structure 13 is set and the size requirements of the effective electrical contact area in the actual application scenario. No specific limitation is made here.

[0207] Exemplarily, in the case where the second conductive semiconductor portion is disposed on the corresponding strip-shaped doping region along the width direction of the strip-shaped doping region, as shown in FIG. Figures 7 to 9As shown, when the second conductive semiconductor portion 18 is disposed on the strip-shaped doping region 14 included in the first doping region, 0.1D2≤X1<0.5D2; and / or, when the second conductive semiconductor portion 18 is disposed on the strip-shaped doping region 14 included in the second doping region, 0.1D3≤X1<0.5D3. For example: when the second conductive semiconductor portion 18 is disposed on the strip-shaped doping region 14 included in the first doping region, X1 may be equal to 0.1D2, 0.2D2, 0.25D2, 0.3D2, 0.35D2 or 0.4D2, etc. For example: when the second conductive semiconductor portion 18 is disposed on the strip-shaped doping region 14 included in the second doping region, X1 may be equal to 0.1D3, 0.2D3, 0.25D3, 0.3D3, 0.35D3 or 0.4D3, etc. In this case, the conductive semiconductor structure 13 is set on the strip doping region 14 included in the first doping region along the width direction of the strip doping region 14 as an example for explanation: the carriers collected by the first doping region need to be led out through the electrode structure in ohmic contact with itself. Based on this, along the width direction of the strip doping region 14, the partial area of ​​the strip doping region 14 included in the first doping region along its own extension direction needs to be directly in ohmic contact with the electrode structure, and the ohmic contact area will occupy a certain width. In this case, when 0.1D2≤X1<0.5D2, it can be prevented that the etching accuracy is strictly required to form the second conductive semiconductor portion 18 with a smaller setting width due to the smaller setting width X1 of the second conductive semiconductor portion 18, thereby reducing the etching difficulty; at the same time, it can also be prevented that when the setting mode corresponding to the second conductive semiconductor portion 18 is an electrical setting, the setting width X1 is small, so that the effective electrical contact area corresponding to the conductive semiconductor structure is also small, resulting in poor effect of reducing the risk of hot spots by setting a conductive semiconductor structure in the back contact battery. In addition, it can also prevent the electrode structure from being unable to make ohmic contact with the strip-shaped doping region 14 included in the first doping region due to the large width X1 of the second conductive semiconductor portion 18, ensuring that the current collected by the first doping region can be led out through the electrode structure, which is conducive to forming a photocurrent. In addition, the beneficial effect of the above 0.1D3≤X1<0.5D3 is similar to the beneficial effect of 0.1D2≤X1<0.5D2, which will not be repeated here.

[0208] Exemplarily, when the corresponding arrangement of the second conductive semiconductor portion is an electrical arrangement, X1≤W≤40X1, and / or, the effective electrical contact height of the side of the first doping region and the second doping region electrically coupled through the conductive semiconductor structure is Z, and one thousand five hundredth of X1≤Z≤one four hundredth of X1. For example: when the corresponding arrangement of the second conductive semiconductor portion is an electrical arrangement, W can be equal to X1, 5X1, 10X1, 15X1, 20X1, 30X1 or 40X1, etc. For example: when the corresponding arrangement of the second conductive semiconductor portion is an electrical arrangement, Z can be equal to one thousand five hundredth of X1, one thousandth of X1, one eight hundredth of X1, six hundredth of X1 or one four hundredth of X1. In this case, when the corresponding arrangement of the second conductive semiconductor portion is an electrical arrangement, the effective electrical contact area between the conductive semiconductor structure and the first doping region and the second doping region respectively includes not only the contact area between the sidewall of the conductive semiconductor structure and the first doping region or the second doping region, but also the contact area between the second conductive semiconductor portion and the corresponding strip-shaped doping region. Based on this, the size of the above-mentioned effective electrical contact area can be adjusted by adjusting the numerical value of at least one of X1, W and Z, thereby affecting the reverse breakdown voltage corresponding to the back contact battery and the size of the leakage current under normal working conditions. In this case, when X1≤W≤40X1, the width W of the conductive semiconductor structure has a large optional range, and the reverse breakdown voltage corresponding to the back contact battery and the leakage current under normal working conditions can be adjusted by adjusting the width W of the conductive semiconductor structure, which is beneficial to improve the applicability of the back contact battery provided by the embodiment of the present invention in different application scenarios. In addition, when W is within the above range, it can prevent the high manufacturing precision requirements for manufacturing the conductive semiconductor structure due to the small W, which is beneficial to reduce the manufacturing difficulty of the back contact battery; it can also prevent the setting of X1 and / or Z values ​​to be large due to the small W to reduce the reverse breakdown voltage corresponding to the back contact battery to the working requirements, thereby affecting the formation quality of the electrode structure, etc., and improving the yield of the back contact battery. At the same time, it can also prevent the leakage current corresponding to the single conductive semiconductor structure from being large due to the large W, ensuring that the back contact battery has high working performance under normal working conditions. In addition, the beneficial effect of one thousand five hundredth of X1 ≤ Z ≤ one four hundredth of X1 is similar to the beneficial effect of X1 ≤ W ≤ 40X1, and will not be repeated here.

[0209] Exemplarily, when the configuration corresponding to the second conductive semiconductor portion is an electrical configuration, 0.03mm≤X1≤0.2mm; and / or, 0.03mm≤W≤8mm. For example: when the configuration corresponding to the second conductive semiconductor portion is an electrical configuration, X1 can be equal to 0.03mm, 0.08mm, 0.1mm, 0.15mm, 0.18mm or 0.2mm, etc. For example: when the configuration corresponding to the second conductive semiconductor portion is an electrical configuration, W can be equal to 0.03mm, 0.5mm, 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm or 8mm, etc. In this case, when X1 is within the above range, it can prevent the high manufacturing precision requirements due to the small X1, and reduce the difficulty of manufacturing the back contact battery; it can also prevent the small X1, which makes the effective electrical contact area corresponding to the conductive semiconductor structure also small, resulting in poor effect of reducing the risk of hot spots of the back contact battery by setting the conductive semiconductor structure. In addition, it can prevent the electrode structure from being difficult to manufacture and / or the contact resistance between the electrode structure and the strip doping region from being large due to the small width of the portion of the strip doping region reserved along its width direction for ohmic contact with the electrode structure, which is beneficial to improving the yield of the back contact battery and the contact performance between the electrode structure and the strip doping region. In addition, the beneficial effects of W within the above range can be referred to in the previous text and will not be repeated here.

[0210] Exemplarily, when the configuration corresponding to the second conductive semiconductor portion is an insulating configuration, one sixteen thousandth of W ≤ Z ≤ one twenty-fifth of W. For example: in this case, the side effective electrical contact height Z may be equal to one sixteen thousandth of W, one fifteen thousandth of W, one twelve thousandth of W, one ten thousandth of W, or one twenty-fifth of W, etc. In this case, regardless of whether the conductive semiconductor structure is disposed on at least one of the first doping region and the second doping region, the effective electrical contact area between the conductive semiconductor structure and the first doping region and the second doping region, respectively, is only the effective electrical contact area between the side surfaces of the first doping region and the second doping region and the conductive semiconductor structure, respectively, that is, the product of W and Z. In the above case, by adjusting the numerical values ​​of W and Z, the reverse breakdown voltage of the back contact battery and the leakage current under normal operation can be adjusted, which is beneficial to improve the applicability of the back contact battery provided by the embodiment of the present invention in different application scenarios. In other words, when W and Z satisfy the above-mentioned size relationship range, it can prevent the back contact battery from having a large leakage current under normal working conditions due to an unreasonable setting of the proportional relationship between W and Z, which results in a larger effective electrical contact area, thereby ensuring that the back contact battery has higher working performance; it can also prevent the back contact battery from having a smaller reaction breakdown voltage due to an unreasonable setting of the proportional relationship between W and Z, which results in a smaller effective electrical contact area, thereby ensuring that the back contact battery has a lower risk of hot spots.

[0211] Exemplarily, the above-mentioned effective side electrical contact height Z can satisfy: 0.00005mm≤Z≤0.002mm. For example: the effective side electrical contact height Z can be 0.00005mm, 0.0001mm, 0.0002mm, 0.0003mm, 0.0004mm, 0.0005mm, 0.0.001mm or 0.002mm, etc. In this case, in the actual application process, for the consideration of carrier shunting capacity and consumables usage, the first doping region and the second doping region included in the back contact battery usually have a reasonable thickness (or depth) range. In addition, the size of the above-mentioned side effective electrical contact height Z will affect the effective electrical contact area of ​​the conductive semiconductor structure with the first doping region and the second doping region, respectively, and thus affect the leakage current size of the first doping region and the second doping region through the local conduction of a single conductive semiconductor structure. In this case, the above-mentioned effective electrical contact height Z on the side is within the above-mentioned range, which can prevent the effective electrical contact area corresponding to the conductive semiconductor structure from being too large or too small, resulting in a poor balance between the hot spot risk of the back contact battery and the working efficiency under normal operation. In addition, it can also prevent the side effective electrical contact height Z from being too large, which leads to an increase in the amount of materials used to manufacture the conductive semiconductor structure, which is beneficial to controlling the manufacturing cost of the back contact battery.

[0212] Exemplarily, in the case where the second conductive semiconductor portion is disposed on the corresponding strip-shaped doping region along the extension direction of the strip-shaped doping region, as Fig.10As shown, when the second conductive semiconductor portion 18 is disposed on the strip-shaped doping region 14 included in the first doping region, 0.1D2≤X2≤1.2D2; and / or, when the second conductive semiconductor portion 18 is disposed on the strip-shaped doping region 14 included in the second doping region, 0.1D3≤X2≤1.2D3. For example: when the second conductive semiconductor portion 18 is disposed on the strip-shaped doping region 14 included in the first doping region, X2 may be equal to 0.1D2, 0.3D2, 0.6D2, 0.9D2, D2 or 1.2D2, etc. For example: when the second conductive semiconductor portion 18 is disposed on the strip-shaped doping region 14 included in the first doping region, X2 may be equal to 0.1D3, 0.3D3, 0.6D3, 0.9D3, D3 or 1.2D3, etc. In this case, the conductive semiconductor structure 13 is set on the strip doping region 14 included in the first doping region along the extension direction of the strip doping region 14 as an example for explanation: As mentioned above, the carriers collected by the first doping region need to be led out through the electrode structure in ohmic contact with itself. In addition, the extension length of the electrode structure on the strip doping region 14 included in the first doping region will affect the contact resistance between itself and the first doping region, and the carriers collected by each part of the strip doping region 14 included in the first doping region can be timely led out through the electrode structure. Based on this, when 0.1D2≤X2≤1.2D2, it can be prevented that the etching accuracy is strictly required due to the formation of the conductive semiconductor structure 13 with a smaller setting width due to the smaller setting width X2 of the second conductive semiconductor part 18, which is conducive to reducing the manufacturing difficulty of the back contact battery; at the same time, it can also be prevented that when the setting mode corresponding to the second conductive semiconductor part 18 is an electrical setting, the setting width X2 is small, so that the effective electrical contact area corresponding to the conductive semiconductor structure is also small, resulting in poor effect of reducing the risk of hot spots by setting the conductive semiconductor structure in the back contact battery. In addition, it can also prevent the end of the electrode structure along the extension direction of the strip doping region 14 from being too far away from the edge of the strip doping region 14, which causes the carriers collected at the edge of the strip doping region 14 along the length direction to be unable to be promptly extracted due to the large width X2 of the second conductive semiconductor portion 18, thereby ensuring that the back contact battery has good working performance. As for the beneficial effects of 0.1D3≤X2≤1.2D3, reference can be made to the beneficial effects analysis of 0.1D2≤X2≤1.2D2, which will not be repeated here.

[0213] For example, Fig.10As shown, along the extension direction of the strip-shaped doped region 14, the setting width X3 of the second conductive semiconductor portion 18 can satisfy: 0.1W1≤X3≤0.3W1. For example: X3 can be equal to 0.1W1, 0.12W1, 0.14W1, 0.16W1, 0.18W1, 0.2W1, 0.24W1, 0.28W1 or 0.3W1, etc. In this case, in the actual application process, the electrode structure will also be formed above the connection area 15, and may even be in ohmic contact with the connection area 15. Based on this, the portion of the electrode structure located above the connection area 15 needs to occupy a certain width of the connection area 15. In this case, when 0.1W1≤X3≤0.3W1, it can prevent the second conductive semiconductor portion 18 from having a smaller width X3, which results in strict requirements on etching accuracy for forming a conductive semiconductor structure 13 with a smaller width, thereby reducing the difficulty of etching; at the same time, it can also prevent the second conductive semiconductor portion 18 from having a smaller width X3, which results in a smaller effective electrical contact area corresponding to the conductive semiconductor structure, resulting in poor effect of reducing the risk of hot spots by setting a conductive semiconductor structure in a back contact battery when the setting mode corresponding to the second conductive semiconductor portion 18 is an electrical setting. In addition, it can also prevent the electrode structure from being difficult to form on a smaller width area of ​​the connection area 15 exposed outside the second conductive semiconductor portion 18 due to a larger X3, which is beneficial to reducing the difficulty of manufacturing the electrode structure, and can also prevent the electrode structure from having a smaller width formed on the connection area 15, resulting in a larger transmission resistance corresponding to the electrode structure, thereby ensuring that the electrode structure has good transmission performance.

[0214] As for the thickness H of the conductive semiconductor structure, as mentioned above, the value of H may be related to the size of the above-mentioned effective electrical contact height Z of the side surface, so it can be determined according to the specific formation process of the conductive semiconductor structure and the effective electrical contact area between the conductive semiconductor structure and the first doping region and the second doping region in the actual application scenario, and no specific limitation is made here. It can be understood that if Figure 6 As shown, when the conductive semiconductor structure 13 is continuous with the second doping region 12, the thickness of the conductive semiconductor structure 13 is equal to the thickness of the second doping region 12. Figure 5 As shown, when the conductive semiconductor structure 13 is integrally continuous with the first doping region 11 , the thickness of the conductive semiconductor structure 13 is equal to the thickness of the first doping region 11 .

[0215] In terms of quantity, the back contact cell provided by the embodiment of the present invention may include only one conductive semiconductor structure. Fig.50 and Fig.51As shown, the back contact cell may also include a plurality of conductive semiconductor structures 13. Furthermore, adjacent conductive semiconductor structures 13 are arranged at intervals. In this case, it is possible to prevent a large local leakage current between the first doping region and the second doping region caused by adjacent different conductive semiconductor structures 13 contacting each other.

[0216] Wherein, in the case where the back contact cell includes a plurality of conductive semiconductor structures, the orthographic projection areas of the different conductive semiconductor structures on the backlight side may be equal or unequal. Fig.50 and Fig.51 When the orthographic projection areas of different conductive semiconductor structures 13 on the backlight side are equal, it is beneficial to make the corresponding leakage currents of the first doping region and the second doping region equal after being electrically connected to the different conductive semiconductor structures 13, thereby making the reverse breakdown voltages of the built-in diodes arranged in different areas between the first doping region and the second doping region equal, thereby preventing the problem of battery burning due to local heat concentration when the back contact battery is blocked, and further reducing the hot spot risk of the photovoltaic module including the back contact battery provided by the embodiment of the present invention.

[0217] In addition, it can be understood that when the width W of the conductive semiconductor structure satisfies 0.5D1≤W≤6D1, the number of conductive semiconductor structures included in the back contact cell affects the sum of the orthographic projection areas of all conductive semiconductor structures on the backlight side, thereby affecting the working efficiency of the photovoltaic module including the back contact cell in the normal voltage region, and affecting the reverse breakdown voltage of the back contact cell. Therefore, the number of conductive semiconductor structures included in the back contact cell and the area ratio of the sum of the orthographic projection areas of all conductive semiconductor structures on the backlight side can be determined based on the requirements of the above two situations in the actual application scenario.

[0218] Exemplarily, the sum of the orthographic projection areas of the portions of all the conductive semiconductor structures located between the first doping region and the second doping region on the backlight side is S3, the area of ​​the backlight side is S2, and the ratio of S3 to S2 can be greater than or equal to 0.002% and less than or equal to 20%. For example, the ratio of S3 to S2 can be 0.002%, 0.01%, 0.1%, 1%, 5%, 10%, 15% or 20%, etc. In this case, the ratio of S3 to S2 is within the above range, which can prevent the orthographic projection area of ​​a single conductive semiconductor structure on the backlight side from being small and / or the number of conductive semiconductor structures set on the backlight side from being small due to the small ratio of S3 to S2, and ensure that the back contact battery reduces its own reverse breakdown voltage to a range that meets the working requirements due to the setting of a reasonable number and a reasonable orthographic projection area of ​​conductive semiconductor structures. In addition, it can also prevent the photovoltaic module including the back contact cell from having poor working efficiency in the forward voltage region due to a large ratio of S3 to S2, which results in a large positive projection area of ​​a single conductive semiconductor structure on the backlight side and / or a large number of conductive semiconductor structures arranged on the backlight side.

[0219] As for the number of conductive semiconductor structures disposed on the backlight side, it can be understood that Figure 52 to Figure 55 As shown, when the size of each conductive semiconductor structure 13 is fixed, the more conductive semiconductor structures 13 are formed on the backlight side, the larger the sum of the positive projection areas of the conductive semiconductor structures 13 on the backlight side. Secondly, within a certain range, the more conductive semiconductor structures 13 are formed, the lower the reverse breakdown voltage corresponding to the back contact battery is. However, if more conductive semiconductor structures 13 are arranged on the backlight side beyond the corresponding range, the change amplitude of the reverse breakdown voltage corresponding to the back contact battery is small or even no longer changes. When the number of conductive semiconductor structures 13 increases to a larger range, the working efficiency of the back contact battery will decrease as the leakage current increases. Based on this, it can be determined according to the division of the back contact battery, the size of the conductive semiconductor structure 13, and the requirements for the reverse breakdown voltage and working efficiency of the back contact battery in the actual application scenario.

[0220] Exemplarily, in the case where the back contact cell is a whole back contact cell, the number of the conductive semiconductor structures included in the back contact cell may be greater than or equal to 30 and less than or equal to 8000. For example: in the case where the back contact cell is a whole back contact cell, the number of the conductive semiconductor structures included in the back contact cell may be 30, 300, 400, 450, 500, 800, 1000, 1500, 2000, 2500, 3000 or 8000, etc. In the case of adopting the above technical solution, in the case where the back contact cell is a whole back contact cell, the number of the conductive semiconductor structures included in the back contact cell is set to be greater than or equal to 30 and less than or equal to 8000, which can prevent the reverse breakdown voltage corresponding to the back contact cell from being reduced due to the small number of conductive semiconductor structures, and ensure that the hot spot risk of the back contact cell can be reduced to within the working requirements. In addition, it can also prevent the working efficiency of the photovoltaic module including the back contact cell provided by the embodiment of the present invention from being reduced due to the setting of more conductive semiconductor structures.

[0221] Exemplarily, in the case where the back contact cell is a one-N slice back contact cell, the number of conductive semiconductor structures included in the back contact cell may be greater than or equal to 30 / N and less than or equal to 8000 / N; N is a positive integer greater than or equal to 2. For example: in the case where the back contact cell is a one-half back contact cell, the number of conductive semiconductor structures included in the back contact cell may be 15, 120, 150, 175, 200, 300, 500, 800, 1000, 1200, 1500 or 1650, etc. The beneficial effects in this case can refer to the beneficial effect analysis described above in which the number of conductive semiconductor structures included in the back contact cell is greater than or equal to 30 and less than or equal to 8000 in the case where the back contact cell is a whole back contact cell, and no further description is given here.

[0222] Specifically, in actual application, the number of the conductive semiconductor structures included in the back contact cell can be further determined according to the ratio between the width W of the conductive semiconductor structure and D1.

[0223] Exemplarily, when the ratio of W to D1 is greater than or equal to 0.5 and less than or equal to 2, if the back contact cell is a whole back contact cell, the number of conductive semiconductor structures included in the back contact cell may be greater than or equal to 30 and less than or equal to 2000. If the back contact cell is a 1 / N slice back contact cell, the number of conductive semiconductor structures included in the back contact cell may be greater than or equal to 30 / N and less than or equal to 2000 / N.

[0224] Exemplarily, when the ratio of W to D1 is greater than 2 and less than or equal to 3, if the back contact cell is a whole back contact cell, the number of conductive semiconductor structures included in the back contact cell may be greater than or equal to 350 and less than or equal to 1530. If the back contact cell is a 1 / N slice back contact cell, the number of conductive semiconductor structures included in the back contact cell may be greater than or equal to 350 / N and less than or equal to 1530 / N.

[0225] In addition, as mentioned above, when the conductive semiconductor structure is also arranged on the portion in the first doping region and the second doping region that is in electrical contact with itself, the different arrangement of the conductive semiconductor structure may also cause the size of the effective electrical contact area corresponding to the conductive semiconductor structure to change, thereby affecting the reverse breakdown voltage of the back contact battery and the leakage current size under normal operation. Based on this, the number of conductive semiconductor structures arranged on the backlight side under different arrangement methods can be determined according to the requirements for the reverse breakdown voltage and leakage current size of the back contact battery under normal operation in actual application scenarios, and no specific limitation is made here.

[0226] Exemplarily, in the case where the conductive semiconductor structure is electrically disposed on a portion of the first doping region and / or the second doping region that is in electrical contact with itself, when the back contact cell is a whole-piece back contact cell, the number of the conductive semiconductor structures disposed on the backlight side may be greater than or equal to 30 and less than or equal to 4000; when the back contact cell is a one-Nth slice back contact cell, the number of the conductive semiconductor structures disposed on the backlight side may be greater than or equal to 30 / N and less than or equal to 4000 / N; N is a positive integer greater than or equal to 2. For example: in the case where the conductive semiconductor structure is electrically disposed on a portion of the first doping region and / or the second doping region that is in electrical contact with itself, when the back contact cell is a whole-piece back contact cell, the number of the conductive semiconductor structures disposed on the backlight side may be 30, 100, 500, 1000, 1500, 2000, 2500, 3000, 3500 or 4000, etc. For example: in the case where the conductive semiconductor structure is electrically arranged on the portion in the first doping region and / or the second doping region that is in electrical contact with itself, when the back contact battery is a half-slice back contact battery, the number of the conductive semiconductor structures arranged on the backlight side can be 15, 100, 300, 500, 1000, 1500 or 2000, etc. In this case, when other factors are the same, compared with the portion in which the conductive semiconductor structure is insulated and arranged in the first doping region and / or the second doping region that is in electrical contact with itself, when the conductive semiconductor structure is electrically arranged on the portion in the first doping region and / or the second doping region that is in electrical contact with itself, the effective electrical arrangement area corresponding to the conductive semiconductor structure is larger. Based on this, in the case where the conductive semiconductor structure is electrically arranged on the portion in the first doping region and / or the second doping region that is in electrical contact with itself, the number of the conductive semiconductor structures arranged on the backlight side is within the above range, which can prevent the reverse breakdown voltage corresponding to the back contact battery from being reduced due to the small number of conductive semiconductor structures, and ensure that the hot spot risk of the back contact battery can be reduced to within the working requirements. In addition, it is also possible to prevent the working efficiency of the photovoltaic module including the back contact cell provided by the embodiment of the present invention from being affected due to the provision of more conductive semiconductor structures.

[0227] Exemplarily, in the case where the conductive semiconductor structure is insulated and arranged in the first doping region and / or the second doping region in electrical contact with itself, when the back contact cell is a whole back contact cell, the number of conductive semiconductor structures arranged on the backlight side may be greater than or equal to 5000 and less than or equal to 8000; when the back contact cell is a one-N slice back contact cell, the number of conductive semiconductor structures arranged on the backlight side may be greater than or equal to 5000 / N and less than or equal to 8000 / N; N is a positive integer greater than or equal to 2. For example: in the case where the conductive semiconductor structure is insulated and arranged in the first doping region and / or the second doping region in electrical contact with itself, when the back contact cell is a whole back contact cell, the number of conductive semiconductor structures arranged on the backlight side may be 5000, 5500, 6000, 6500, 7000, 7500 or 8000, etc. For example: in the case where the conductive semiconductor structure is insulated and arranged in the first doping region and / or the second doping region in electrical contact with itself, when the back contact battery is a whole back contact battery, the number of the conductive semiconductor structures arranged on the backlight side can be 2500, 2800, 3000, 3200, 3500, 3800 or 4000, etc. In this case, when other factors are the same, compared with the conductive semiconductor structure being electrically arranged in the first doping region and / or the second doping region in electrical contact with itself, when the conductive semiconductor structure is insulated and arranged in the first doping region and / or the second doping region in electrical contact with itself, the effective electrical arrangement area corresponding to the conductive semiconductor structure is smaller. Based on this, in the case where the conductive semiconductor structure is insulated and arranged in the first doping region and / or the second doping region in electrical contact with itself, the reverse breakdown voltage of the back contact battery can be reduced to the target range by reasonably arranging a large number of conductive semiconductor structures on the backlight side. Based on this, the number of conductive semiconductor structures arranged on the backlight side is within the above range, which can prevent the reverse breakdown voltage of the back contact battery from being reduced too much due to the small number of conductive semiconductor structures, and ensure that the hot spot risk of the back contact battery can be reduced to within the working requirements. In addition, it can also prevent the working efficiency of the photovoltaic module including the back contact battery provided by the embodiment of the present invention from being reduced due to the arrangement of more conductive semiconductor structures.

[0228] Combine the following Fig.56 Table 1 and Table 2 illustrate four specific embodiments and one comparative example of the back contact battery provided by the embodiment of the invention. Fig.11 As shown, in the back contact cell corresponding to Example 1, each strip doped region 14 is provided with a second conductive semiconductor portion 18 on both sides along the width direction, and the number of second conductive semiconductor portions 18 provided is 6732, and the sum of the effective electrical contact areas corresponding to all conductive semiconductor structures 13 on the backlight side is 242.4 mm 2 .

[0229] In the back contact cell corresponding to Example 2, the conductive semiconductor structure is arranged on both sides of the electrical connection point (the point connection point refers to the point where the electrode structure is connected to the interconnection member in the string such as the welding strip) along the extension direction of the strip-shaped doped region, and the number of the second conductive semiconductor parts is 672, and the sum of the effective electrical contact areas corresponding to all the conductive semiconductor structures on the backlight side is 31.2 mm 2 .

[0230] Example 3 is based on Example 1. Along the width direction of the strip doping region, every 7 strip doping regions are followed by the next strip doping region. Second conductive semiconductor portions are arranged on both sides along the width direction, and the number of second conductive semiconductor portions is 884. The sum of the effective electrical contact areas corresponding to all conductive semiconductor structures on the backlight side is 31.8 mm 2 .

[0231] Example 4 is based on Example 3, and the area corresponding to the second conductive semiconductor part is reduced. At this time, the number of second conductive semiconductor parts is still 884, but the sum of the effective electrical contact areas corresponding to all conductive semiconductor structures on the backlight side is 7.96 mm 2 .

[0232] The comparative example is Figure 1 As shown, the first doped region and the second doped region are completely isolated from each other.

[0233] Table 1 Comparison of parameters of back contact cells corresponding to Examples 1 to 4

[0234]

[0235]

[0236] Depend on Fig.56 It can be seen from the data shown in Table 1 that due to the provision of a conductive semiconductor structure, the maximum reverse voltage of the back contact battery corresponding to Examples 1 to 4 is less than the maximum reverse voltage corresponding to the comparative example. In addition, the number of conductive semiconductor structures in Example 3 is less than the number of conductive semiconductor structures provided in Example 1, so the maximum reverse voltage and hot spot temperature of the back contact battery corresponding to Example 3 are greater than the maximum reverse voltage and hot spot temperature of the back contact battery corresponding to Example 1. Furthermore, the provision area of ​​the conductive semiconductor structure in Example 4 is less than the provision area of ​​the conductive semiconductor structure in Example 3, so the maximum reverse voltage of the back contact battery corresponding to Example 4 is greater than the maximum reverse voltage of the back contact battery corresponding to Example 1.

[0237] As for the distribution of different conductive semiconductor structures on the backlight side, the position of each conductive semiconductor structure on the backlight side can be randomly set. Fig.50 and Fig.51 As shown, different conductive semiconductor structures 13 are evenly distributed on the backlight side. In this case, it is beneficial to make the reverse breakdown voltage of the built-in diode formed between different regions of the first doping region and the corresponding regions of the second doping region after the conductive semiconductor structure 13 is set equal, thereby preventing the problem of battery burning due to local heat concentration when the back contact battery is blocked, and further reducing the hot spot risk of the photovoltaic module including the back contact battery provided by the embodiment of the present invention.

[0238] In actual application, Figure 57 to Figure 62 Several optional distribution modes of the conductive semiconductor structure 13 in different unit regions on the backlight side are shown. Figures 25 to 30 The several ways shown make the different conductive semiconductor structures 13 evenly distributed on the backlight side. The embodiment of the present invention does not specifically limit the distribution of the different conductive semiconductor structures 13 on the backlight side.

[0239] For example, Fig.50 and Fig.51 As shown, different conductive semiconductor structures 13 can be distributed in a matrix on one side of the backlight surface. Adjacent rows of the conductive semiconductor structures 13 distributed in a matrix are aligned or staggered. Among them, in the conductive semiconductor structures 13 distributed in a matrix, one conductive semiconductor structure 13 in each row is aligned or staggered with the corresponding conductive semiconductor structure 13 in the adjacent row. It is also possible that in the conductive semiconductor structures 13 distributed in a matrix, at least two conductive semiconductor structures 13 arranged oppositely in each row are aligned or staggered with the corresponding at least two conductive semiconductor structures 13 arranged oppositely in the adjacent row.

[0240] In this case, the distribution of different conductive semiconductor structures 13 on the backlight side is relatively regular, and the adjacent rows of the matrix-shaped conductive semiconductor structures 13 also have two distribution modes: alignment and staggered arrangement. This helps to reduce the difficulty of manufacturing the conductive semiconductor structure 13, and also helps to make the conductive semiconductor structure 13 evenly distributed on the backlight side, further preventing the problem of battery burning due to local heat concentration when the back contact battery is blocked.

[0241] Wherein, when adjacent rows of the conductive semiconductor structures are staggered in a matrix arrangement, the staggered distance L between two adjacent rows of conductive semiconductor structures may be any value greater than 0 and less than the geometric center distance L1 of two adjacent conductive semiconductor structures in the same row.

[0242] For example, Fig.51 As shown, in the case where the conductive semiconductor structures 13 distributed in a matrix are staggered between adjacent rows, the staggered distance L between two adjacent rows of conductive semiconductor structures 13 is equal to half of the geometric center distance L1 between two adjacent conductive semiconductor structures 13 in the same row. In this case, it is beneficial to make the distribution density of the conductive semiconductor structures 13 between different regions of the first doping region 11 and the corresponding regions of the second doping region 12 substantially the same, thereby preventing the problem of the back contact battery being blocked due to the local heat concentration that may cause the battery to burn out due to the long region between the first doping region 11 and the second doping region 12 that is physically isolated by the insulating groove or the insulating material.

[0243] In actual application, Fig.63 As shown, the above-mentioned back contact battery may further include a surface passivation layer 19 and an electrode structure 20. The surface passivation layer 19 is formed at least on the first doping region 11, the second doping region 12 and the conductive semiconductor structure 13. The electrode structure 20 penetrates the surface passivation layer 19 and is in ohmic contact with the first doping region 11 and the second doping region 12 respectively. The portion where the electrode structure 20 is electrically coupled to the first doping region 11 and the portion where the electrode structure 20 is electrically coupled to the second doping region 12 are insulated from each other.

[0244] Specifically, the present invention does not specifically limit the materials and thicknesses of the surface passivation layer and the electrode structure, as long as they can be applied to the back contact battery provided by the present invention. Fig.63 As shown, the conductive semiconductor structure 13 may be arranged on the portion of the first doping region 11 and / or the second doping region 12 that is in electrical contact with itself. In this case, the conductive semiconductor structure 13 will also occupy a certain range on the portion of the first doping region 11 and / or the second doping region 12 that is in electrical contact with itself, which may affect the manufacture of the electrode structure 20. Based on this, it can be determined according to the requirements for the manufacturing accuracy of the electrode structure 20, the contact performance of the electrode structure 20, and the effective electrical contact area corresponding to the conductive semiconductor structure 13 in the actual application scenario, and is not specifically limited here.

[0245] Exemplarily, along the direction parallel to the backlight surface, the minimum spacing D4 between the electrode structure and the portion of the surface passivation layer covering the conductive semiconductor structure may be greater than or equal to 30 μm and less than or equal to 250 μm. For example, along the direction parallel to the backlight surface, the minimum spacing D4 between the electrode structure and the portion of the surface passivation layer covering the conductive semiconductor structure may be 30 μm, 50 μm, 80 μm, 100 μm, 150 μm, 200 μm, 220 μm or 250 μm, etc. In this case, in the actual application process, the equipment for manufacturing the electrode structure often has a certain processing error, which causes a certain deviation between the target formation range of the electrode structure and the actual formation range. Based on this, the minimum spacing D4 between the electrode structure and the portion of the surface passivation layer covering the conductive semiconductor structure is within the above range, which can prevent the electrode structure from being at least partially formed above the conductive semiconductor structure due to the small minimum spacing D4, and the collected carriers of the first doping region and / or the second doping region cannot be timely derived. In addition, it can also prevent the conductive semiconductor structure from being smaller in width than the first doping region and the second doping region due to the larger minimum spacing D4, thereby ensuring that each conductive semiconductor structure has a relatively large effective electrical contact area, which is beneficial to reducing the reverse breakdown voltage of the back contact battery.

[0246] In a second aspect, an embodiment of the present invention provides a photovoltaic module, which includes the solar cell provided by the first aspect and various implementations thereof.

[0247] The beneficial effects of the second aspect and its various implementations in the embodiments of the present invention can be analyzed by referring to the beneficial effects of the first aspect and its various implementations, and will not be elaborated here.

[0248] In a third aspect, an embodiment of the present invention further provides a method for manufacturing a back-contact battery, the method for manufacturing a back-contact battery comprising the following steps:

[0249] First, a semiconductor substrate is provided.

[0250] Next, a first doping region and a second doping region are formed on the backlight side of the semiconductor substrate; the first doping region and the second doping region are alternately distributed on the backlight side of the semiconductor substrate, and the conductivity types of the first doping region and the second doping region are opposite; along the arrangement direction of the first doping region and the second doping region, the area between the first doping region and the second doping region is the spacing area.

[0251] Next, a conductive semiconductor structure is formed on the backlight side of the semiconductor substrate; the conductive semiconductor structure includes a first conductive semiconductor portion and a second conductive semiconductor portion that are electrically contacted; the first conductive semiconductor portion is located in the spacing area, and the conductivity type of the first conductive semiconductor portion is opposite to the conductivity type of one of the first doping region and the second doping region; only a portion of the first doping region and only a portion of the second doping region are respectively electrically connected to at least the first conductive semiconductor portion; the second conductive semiconductor portion is arranged above a portion of the first doping region and / or the second doping region that is away from the semiconductor substrate.

[0252] Specifically, the backlight surface of the semiconductor substrate may have first regions and second regions that are alternately distributed, and a spacing region between the first region and the second region adjacent to the first region.

[0253] Among them, the boundaries between the first region, the second region and the spacing region on the backlight side of the semiconductor substrate are virtual boundaries. A first doped region will be formed in the first region later. Therefore, the range of the first region on the backlight side can be determined according to the formation range of the first doped region in the actual application scenario. A second doped region will be formed in the second region later. Therefore, the range of the first region on the backlight side can be determined according to the formation range of the first doped region in the actual application scenario. As for the spacing region, after the ranges of the first region and the second region are determined, the range of the spacing region between the first region and the second region adjacent to itself is determined. Among them, the materials and dimensions of the above-mentioned first doped region, second doped region and conductive semiconductor structure can be referred to the previous text and will not be repeated here.

[0254] In the actual manufacturing process, the manufacturing process of forming the first doping region, the second doping region and the conductive semiconductor structure on the backlight side of the semiconductor substrate is divided into the following two types for explanation:

[0255] The first method is to form a first doped region in the first area.

[0256] In the actual manufacturing process, a process such as chemical vapor deposition can be used to form a whole intrinsic semiconductor layer on the backlight side, and diffusion or ion implantation can be used to dope the intrinsic semiconductor layer to obtain a doped semiconductor material. Then, a laser etching process or dry etching or wet etching under the mask of a corresponding mask plate is used to selectively etch the doped semiconductor material to remove the portion of the doped semiconductor material corresponding to the second region and the spacing region to obtain the first doped region.

[0257] Wherein, when the intrinsic semiconductor layer is doped by a diffusion process and the intrinsic semiconductor layer is silicon, a doped silicon glass layer or a conductive doped silicon glass layer is also formed on the side of the first doped region away from the semiconductor substrate. In addition, when the manufactured back-contact battery also includes a passivation layer located between the first doped region and the first area, a process such as chemical vapor deposition can be used before forming the above-mentioned intrinsic semiconductor layer to form a passivation material layer arranged in an entire layer on the backlight side. Then, while selectively etching the doped semiconductor material, the above-mentioned passivation material layer is selectively etched to obtain a passivation layer located between the first doped region and the semiconductor substrate. Of course, before forming the intrinsic semiconductor layer, deposition and etching processes can be used to form a passivation layer only in the first area.

[0258] Next, if Fig.11 As shown, a doped semiconductor material layer is formed in the first doping region 11, the spacing region and the second region as a whole.

[0259] In the actual manufacturing process, chemical vapor deposition and other processes can be used to form a whole layer of intrinsic semiconductor layer in the first doping area, the spacing area and the second area, and the intrinsic semiconductor layer is doped by diffusion or ion implantation to obtain a doped semiconductor material layer.

[0260] Wherein, when the intrinsic semiconductor layer is doped by a diffusion process and the intrinsic semiconductor layer is silicon, a doped silicon glass layer or a conductive doped silicon glass layer is also formed on the side of the doped semiconductor material layer facing away from the semiconductor substrate.

[0261] Next, if Fig.11 As shown, the doped semiconductor material layer is selectively etched to remove the portion of the doped semiconductor material layer corresponding to the first doped region 11 and the portion of the spacing region; after selective etching, the doped semiconductor material layer forms a second doped region 12 and at least one conductive semiconductor structure 13; the second doped region 12 is located in the second region; the second doped region 12 and the first doped region 11 have opposite conductivity types, and the second doped region 12 and the conductive semiconductor structure 13 have the same conductivity type; only a portion of the first doped region 11 and only a portion of the second doped region 12 are electrically in contact with at least one conductive semiconductor structure 13, respectively; the conductive semiconductor structure 13 includes a first conductive semiconductor portion 17 and a second conductive semiconductor portion 18 that are continuous as a whole; the first conductive semiconductor portion 17 is located between the first doped region 11 and the second doped region 12, and the second conductive semiconductor portion 18 is arranged above the portion of the first doped region 11 that is away from the semiconductor substrate.

[0262] In the actual application process, a laser etching process is used, or a dry etching process or a wet etching process is used under the mask of a corresponding mask plate to selectively etch the doped semiconductor material layer, remove the portion of the doped semiconductor material layer corresponding to the first region and the portion of the spacing region, and obtain the second doped region and the conductive semiconductor structure. Fig.11 The left schematic diagram in the figure is a schematic diagram of selectively etching an area (corresponding to the area where the grid in the figure is located) after forming a doped semiconductor material layer. Fig.11 The right schematic diagram in FIG. 1 is a schematic diagram after selective etching to form a second doped region and a conductive semiconductor structure.

[0263] It can be understood that, under this manufacturing method, if the material of the first doped region is silicon and the first doped region is diffused by a diffusion process, then after the conductive semiconductor structure is formed, there is a doped silicon glass layer or a conductive doped silicon glass layer between the second conductive semiconductor portion included in the conductive semiconductor structure and the first doped region located directly below it. Alternatively, before forming the intrinsic semiconductor layer used to manufacture the second doped region and the conductive semiconductor structure, the doped silicon glass layer or the conductive doped silicon glass layer located on the first doped region can be removed, and the second conductive semiconductor portion included in the conductive semiconductor structure can be directly in contact with the first doped region located directly below it. Alternatively, when forming the intrinsic semiconductor layer used to manufacture the second doped region and the conductive semiconductor structure, the doped silicon glass layer or the conductive doped silicon glass layer located on the first doped region can be removed, and the corresponding film layer (such as a transparent conductive layer, etc.) required in practice can be formed.

[0264] In addition, when the manufactured back contact battery also includes a passivation layer located between the second doped region and the second area, after forming the first doped region and before forming the intrinsic semiconductor layer for manufacturing the doped semiconductor material layer, chemical vapor deposition and other processes can be used to form a passivation material layer set in the first doped region, the spacing region and the second region. Then, while selectively etching the doped semiconductor material layer, the above passivation material layer is selectively etched to obtain a passivation layer located between the second doped region and the semiconductor substrate, and between the conductive semiconductor structure and the semiconductor substrate. Of course, before forming the intrinsic semiconductor layer, deposition and etching and other processes can be used to form a passivation layer only in the first area.

[0265] The second method: forming a second doping region in the first region. Next, a doped semiconductor material layer is formed in the second doping region, the spacing region, and the second region. Next, the doped semiconductor material layer is selectively etched to remove the portion of the doped semiconductor material layer located in part of the second doping region and part of the spacing region; after selective etching, the doped semiconductor material layer forms a first doping region and at least one conductive semiconductor structure; the first doping region is located in the second region; the first doping region and the second doping region have opposite conductivity types, and the first doping region has the same conductivity type as the conductive semiconductor structure; only part of the first doping region and only part of the second doping region are electrically in contact with at least one conductive semiconductor structure, respectively; the conductive semiconductor structure includes a first conductive semiconductor portion and a second conductive semiconductor portion that are continuous as one; the first conductive semiconductor portion is located between the first doping region and the second doping region, and the second conductive semiconductor portion is arranged above the portion of the second doping region that is away from the semiconductor substrate.

[0266] The specific manufacturing process of the second manufacturing method can refer to the specific manufacturing process of the first manufacturing method described above. The difference between the two is that in the first method, the conductive semiconductor structure is continuously integrated with the second doped region, while in the second method, the conductive semiconductor structure is continuously integrated with the first doped region.

[0267] The beneficial effects of the third aspect and its various implementations in the embodiments of the present invention can be analyzed by referring to the beneficial effects in the corresponding implementations of the first aspect, and will not be elaborated here.

[0268] In addition, in the actual application process, the conductive semiconductor structure can also be formed on the semiconductor substrate separately from the first doping region and the second doping region. Based on this, in the actual manufacturing process, deposition and selective etching processes can be used to form the first doping region in the first area of ​​the backlight surface of the semiconductor substrate, and the second doping region in the second area of ​​the backlight surface of the semiconductor substrate. At this time, the first doping region and the second doping region are alternately spaced. Then, deposition and etching processes are used to form a conductive semiconductor structure at least in part of the spaced region according to the requirements of the actual application scenario for the formation range of the conductive semiconductor structure.

[0269] In the above description, the technical details of the patterning and etching of each layer are not described in detail. However, those skilled in the art should understand that various technical means can be used to form layers, regions, etc. of desired shapes. In addition, in order to form the same structure, those skilled in the art can also design methods that are not completely the same as the methods described above. In addition, although the various embodiments are described above separately, this does not mean that the measures in the various embodiments cannot be used in combination to advantage.

[0270] The embodiments of the present disclosure are described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of the present disclosure. The scope of the present disclosure is defined by the appended claims and their equivalents. Without departing from the scope of the present disclosure, a person skilled in the art may make a variety of substitutions and modifications, which should all fall within the scope of the present disclosure.

Claims

1. A back contact battery, characterized in that: include: A semiconductor substrate, a first doped region, a second doped region, and at least one conductive semiconductor structure; Each of the conductive semiconductor structures is at least partially located between the first doping region and the second doping region, and only a portion of the first doping region and only a portion of the second doping region are respectively in electrical contact with the at least one conductive semiconductor structure; the first doping region and the second doping region have opposite conductivity types, and the conductive semiconductor structure has an opposite conductivity type to that of one of the first doping region and the second doping region; wherein, The first doping region and the second doping region each include a plurality of strip-shaped doping regions and at least one connection region; the strip-shaped doping regions included in the first doping region and the strip-shaped doping regions included in the second doping region are distributed in parallel and alternately at intervals on one side of the backlight surface of the semiconductor substrate; each connection region is electrically connected to a corresponding strip-shaped doping region of the same conductivity type as itself; an extension direction of the connection region is different from an extension direction of the strip-shaped doping region; at least one of the conductive semiconductor structures is at least partially located between a strip-shaped doping region included in one of the first doping region and the second doping region and an adjacent connection region included in the other.

2. The back contact cell according to claim 1, characterized in that: The region between the first doping region and the second doping region is a spacing region; the conductive semiconductor structure comprises a first conductive semiconductor portion and a second conductive semiconductor portion in electrical contact; the first conductive semiconductor portion is located in the spacing region, and the second conductive semiconductor portion is arranged above a portion of the first doping region and / or the second doping region that is away from the semiconductor substrate; Among them, in the first doping region, the width of the strip doping region corresponding to the conductive semiconductor structure is D2; in the second doping region, the width of the strip doping region corresponding to the conductive semiconductor structure is D3.

3. The back contact battery according to claim 2, characterized in that: In the second conductive semiconductor portion, the width of the portion arranged above the strip-shaped doping region included in the first doping region and / or the strip-shaped doping region included in the second doping region along the width direction of the strip-shaped doping region is X1; along the extension direction of the spacing region, the width of the conductive semiconductor structure is W; X1≤W≤40X1, and / or, the effective electrical contact height of the side surface of the first doped region and the second doped region electrically connected through the conductive semiconductor structure is Z, and one thousand five hundredth of X1≤Z≤one four hundredth of X1.

4. The back contact cell according to claim 2, characterized in that: In the second conductive semiconductor portion, a portion disposed above the strip-shaped doping region included in the first doping region and / or the strip-shaped doping region included in the second doping region along the extension direction of the strip-shaped doping region has a width of X2; When the second conductive semiconductor portion is disposed above the strip-shaped doped region included in the first doped region, 0.1D2≤X2≤1.2D2; and / or when the second conductive semiconductor portion is disposed above the strip-shaped doped region included in the second doped region, 0.1D3≤X2≤1.2D3.

5. The back contact cell according to claim 2, characterized in that: In the first doping region and the second doping region, the width of the connection region corresponding to the conductive semiconductor structure is W1; In the second conductive semiconductor portion, a portion disposed on the connection region included in the first doping region and / or the connection region included in the second doping region along the extension direction of the strip-shaped doping region has a width X3; 0.1W1≤X3≤0.3W1.

6. The back contact cell according to claim 2, characterized in that: Along the extension direction of the spacing region, the width of the conductive semiconductor structure is W; the effective electrical contact height of the side surface where the first doped region and the second doped region are electrically connected through the conductive semiconductor structure is Z; When the configuration corresponding to the second conductive semiconductor portion is an insulating configuration, one sixteen thousandth of W≤Z≤one twenty-fifth of W.

7. The back contact cell according to claim 1, characterized in that: The width of the spacing region between the first doping region and the second doping region is D1; ​​along the extension direction of the spacing region, the width of the conductive semiconductor structure is W, and 0.5D1≤W≤3D1.

8. The back contact cell according to claim 1, characterized in that: The width of the connection region, which belongs to one of the first doping region and the second doping region and corresponds to the conductive semiconductor structure, is W1; The length of the strip-shaped doped region that belongs to the other of the first doped region and the second doped region and corresponds to the conductive semiconductor structure is W2; the width of the interval region between the first doped region and the second doped region is D1; Along the width direction of the spacing region, the length of the conductive semiconductor structure is D, and D1≤D≤D1+W1+W2.

9. The back contact cell according to claim 1, characterized in that: The back contact battery includes a plurality of the conductive semiconductor structures; adjacent conductive semiconductor structures are arranged at intervals.

10. The back contact cell according to claim 9, characterized in that: In the case where the back contact cell is a whole back contact cell, the number of the conductive semiconductor structures included in the back contact cell is greater than or equal to 30 and less than or equal to 8000; or, In the case where the back contact cell is a 1 / N sliced ​​back contact cell, the number of the conductive semiconductor structures included in the back contact cell is greater than or equal to 30 / N and less than or equal to 8000 / N; N is a positive integer greater than or equal to 2.

11. A photovoltaic module, characterized in that: Comprising a back contact battery as claimed in any one of claims 1 to 10.

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