A passivation repair method and passivation device for a crystalline silicon-based cell slice section

Abstract

The present application discloses a passivation repair method for a crystalline silicon-based cell slice section, comprising: stacking a plurality of crystalline silicon-based cell slices, and making the sections of the plurality of crystalline silicon-based cell slices coplanar to form a crystalline silicon-based cell slice group to be passivated, placing the crystalline silicon-based cell slice group in a fixed fixture to form a passivation unit; providing a conveying mechanism to convey the passivation unit to an evaporation annealing mechanism, wherein a first source material is provided in the evaporation annealing mechanism, and the first source material is heated and evaporated to form a gaseous first source material under vacuum conditions and a temperature environment of 20°C to 300°C, and the gaseous first source material is deposited on the surface to be passivated for a first passivation layer; the evaporation annealing mechanism anneals the crystalline silicon-based cell slice group in the passivation unit that has completed the deposition of the first passivation layer under a temperature environment of 100°C to 350°C. The above technical solution can solve the problem that the cross-section passivation process of the cell sub-sheet is complicated, time-consuming and labor-intensive, and it is difficult to form a large-scale production of cross-section passivation.

Description

Technical Field

[0001] The present invention relates to the technical field of cell slice passivation, and in particular to a passivation repair method and a passivation device for a crystalline silicon-based cell slice cross section. Background Art

[0002] There are generally two ways to slice the cell: laser scribing plus mechanical splitting, laser thermal splitting without damage splitting, etc. Since the cross-section of the cell sub-cell (half-cell cell or multi-slice cell) formed after segmentation has not been passivated, the edge recombination increases and the conversion efficiency decreases. When the photovoltaic modules produced by this method work under a certain system voltage, the sodium ions in the photovoltaic modules will gather at the cross-section under the action of the electric field, forming a leakage channel, reducing the insulation resistance of the positive and negative electrodes of the photovoltaic modules. This not only reduces the photoelectric conversion efficiency of the photovoltaic modules, but also further leads to a reduction in the reliability of the photovoltaic modules.

[0003] In the related art, the cross-section of the cell sub-chip is passivated by chemical deposition, namely PECVD and ALD. Specifically, the first layer (silicon oxide and / or aluminum oxide layer) is first deposited, and then the second layer (silicon nitride layer) is deposited, and finally light injection hydrogen passivation is performed to repair the cutting damage and improve the conversion efficiency of the cell sub-chip. However, when the above method is implemented, the stacked cell sub-chips are placed in the ALD deposition equipment, preheated in a vacuum environment, and then the first layer is deposited on the cross-section of the cell sub-chip; then the cell sub-chip is taken out and placed in the PECVD reaction equipment, preheated in a vacuum environment, and then an appropriate amount of process gas is introduced, and finally the second layer is deposited on the cross-section of the cell sub-chip, and then the cell sub-chip is placed in the light injection annealing furnace for hydrogen passivation. In the above-mentioned passivation operation, the battery sub-sheet not only has to be processed by multiple devices in sequence, but also has strict requirements on multiple process parameters such as temperature, vacuum pressure, gas flow rate and plasma deposition direction of each device. As a result, the cross-section passivation process of the battery sub-sheet is cumbersome, time-consuming and labor-intensive, making it difficult to form large-scale production of cross-section passivation of battery sub-sheets. Summary of the invention

[0004] The purpose of the present invention is to provide a passivation repair method and a passivation method for a crystalline silicon-based solar cell segment section to solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: a passivation repair method for a crystalline silicon-based solar cell segment, comprising:

[0006] S1, stacking a plurality of crystalline silicon-based solar cell slices to form a crystalline silicon-based solar cell slice group, and making the cross sections of the plurality of crystalline silicon-based solar cell slices coplanar to form a surface to be passivated, placing the crystalline silicon-based solar cell slice group in a fixed fixture to form a passivation unit, wherein each of the surfaces to be passivated is exposed outside the fixed fixture;

[0007] S2. Provide a conveying mechanism to convey the passivation unit to an evaporation annealing mechanism, wherein a first source material is provided in the evaporation annealing mechanism, and under vacuum conditions and a temperature environment of 20° C. to 300° C., the evaporation annealing mechanism heats and evaporates the first source material to form a gaseous first source material, and the gaseous first source material is deposited on the surface to be passivated in the passivation unit to form a first passivation layer;

[0008] S3. The evaporation annealing mechanism performs annealing treatment on the crystalline silicon-based solar cell segment group in the passivation unit on which the first passivation layer has been deposited under a temperature environment of 100° C. to 350° C.

[0009] Preferably, in the step S2, it includes:

[0010] S21, the evaporation annealing mechanism includes an evaporation cavity and an annealing cavity, the evaporation cavity is not connected with the annealing cavity, and the conveying mechanism conveys the passivation unit to the evaporation cavity to deposit the first passivation layer;

[0011] S22, the conveying mechanism conveys the passivation unit on which the first passivation layer has been deposited to the annealing chamber.

[0012] Preferably, the evaporation annealing mechanism is provided with a process chamber, and the passivation unit can sequentially complete the first passivation layer deposition and the annealing treatment in the process chamber.

[0013] Preferably, in the step S2, it includes:

[0014] The surface to be passivated in the passivation unit is transported to the evaporation annealing mechanism after cleaning and drying, or the transport mechanism transports the passivation unit to the evaporation annealing mechanism, and the evaporation annealing mechanism is preheated and vacuumed at the same time, and the preheating temperature is 50-150°C.

[0015] Preferably, in the step S2, the method of heating and evaporating the first source material to form the gaseous first source material comprises:

[0016] The evaporation annealing mechanism is provided with an electron beam gun, and the electron beam gun sprays an electron beam to bombard the first source material to form the gaseous first source material.

[0017] Preferably, in the step S2, the method of heating and evaporating the first source material to form the gaseous first source material comprises:

[0018] The evaporation annealing mechanism is provided with a resistance heating element, and the resistance heating element heats the first source material to form the gaseous first source material.

[0019] Preferably, in the step S2, the method of heating and evaporating the first source material to form the gaseous first source material comprises:

[0020] The evaporation annealing mechanism is provided with a laser emitting component, and the laser emitting component emits laser to heat the first source material to form the gaseous first source material.

[0021] Preferably, in the step S2, it includes:

[0022] The evaporation annealing mechanism is also provided with a second source material. After the first passivation layer is deposited on the surface to be passivated, the evaporation annealing mechanism heats and evaporates the second source material to form a gaseous second source material. The gaseous second source material is used to deposit a second passivation layer on the first passivation layer on the surface to be passivated.

[0023] Preferably, the evaporation annealing mechanism is further provided with the second source material, and after the first passivation layer is deposited on the surface to be passivated, the evaporation annealing mechanism heats and evaporates the second source material to form the gaseous second source material, and the step of depositing the second passivation layer on the first passivation layer on the surface to be passivated using the gaseous second source material comprises:

[0024] The evaporation annealing mechanism comprises a first evaporation chamber, a second evaporation chamber and an annealing chamber which are not interconnected, the first evaporation chamber is provided with the first source material, the second evaporation chamber is provided with the second source material, the conveying mechanism conveys the passivation unit after the first passivation layer is deposited to the second evaporation chamber, under vacuum conditions and a temperature environment of 20° C. to 300° C., the second source material is heated and evaporated to form the gaseous second source material, and the gaseous second source material is used to deposit the second passivation layer on the first passivation layer on the surface to be passivated;

[0025] The conveying mechanism conveys the passivation unit on which the second passivation layer is deposited to the annealing chamber.

[0026] Preferably, in the step S2, it includes:

[0027] The evaporation annealing mechanism is also provided with a second source material. Under vacuum conditions and a temperature environment of 20° C. to 300° C., the evaporation annealing mechanism heats and evaporates the second source material to form a gaseous second source material, and the gaseous second source material is used to deposit a second passivation layer on the surface to be passivated;

[0028] After the second passivation layer is deposited on the surface to be passivated, the evaporation annealing mechanism heats and evaporates the first source material to form the gaseous first source material, and the gaseous first source material is used to deposit the first passivation layer on the second passivation layer.

[0029] Preferably, in the step S2, it includes:

[0030] The passivation unit is located in the evaporation annealing mechanism, the angle formed by the orientation direction of the passivation surface in the passivation unit and the gravity direction is 0~90°, the passivation unit is located above the first source material, and the evaporation annealing mechanism deposits the first passivation layer on the passivation unit while the passivation unit rotates horizontally.

[0031] Preferably, the conveying mechanism can convey the plurality of the passivation units to the evaporation annealing mechanism to complete the deposition of the first passivation layer, and the evaporation annealing mechanism can sequentially complete the deposition of the first passivation layer and annealing treatment of the plurality of the passivation units.

[0032] Preferably, in the step S2, the deposition rate of the gaseous first source material on the surface to be passivated to deposit the first passivation layer is 0.1-20Å / s.

[0033] The present application also discloses a passivation device for implementing the above-mentioned passivation repair method, comprising a stacking mechanism, a sheet moving mechanism, the fixed tooling, the conveying mechanism and the evaporation annealing mechanism, wherein the stacking mechanism is used to stack a plurality of the crystalline silicon-based cell slices to form a crystalline silicon-based cell slice group, the sheet moving mechanism is used to transport the crystalline silicon-based cell slice group and place it in the fixed tooling to form the passivation unit, and the conveying mechanism can carry and drive the passivation unit to move to the evaporation annealing mechanism.

[0034] Preferably, the fixing tool comprises a cavity with an opening and a fastener, the crystalline silicon-based cell slice group can be placed in the cavity, the cross-sections of multiple crystalline silicon-based cell slices in the crystalline silicon-based cell slice group are coplanar and exposed at the opening or flush with the end face of the opening, and the fastener is arranged in the cavity, and the fastener is used to fix the crystalline silicon-based cell slice group in the cavity.

[0035] Preferably, the conveying mechanism includes a conveying channel and a handling hand, the conveying channel can carry and drive the passivation unit to move to the discharge end of the conveying channel, and the handling hand carries the passivation unit at the discharge end to the evaporation annealing mechanism.

[0036] The technical solution adopted in this application can achieve the following beneficial effects:

[0037] On the one hand, the present application discloses a method for repairing the passivation of a crystalline silicon-based cell slice section, comprising:

[0038] S1. Stack a plurality of crystalline silicon-based cell slices to form a crystalline silicon-based cell slice group, and make the cross-sections of the plurality of crystalline silicon-based cell slices coplanar to form a surface to be passivated, and place the crystalline silicon-based cell slice group in a fixed fixture to form a passivation unit, wherein each surface to be passivated is exposed outside the corresponding fixed fixture.

[0039] S2. Provide a conveying mechanism to convey the passivation unit to the evaporation annealing mechanism. The evaporation annealing mechanism is provided with a first source material. Under vacuum conditions and a temperature environment of 20°C to 300°C, the evaporation annealing mechanism heats and evaporates the first source material to form a gaseous first source material. The gaseous first source material is deposited on the surface to be passivated in the passivation unit to form a first passivation layer.

[0040] In this step, by means of physical deposition (i.e., evaporation coating process), the first source material is heated and evaporated to form a gaseous first source material, and the gaseous first source material is deposited on the surface to be passivated in the passivation unit to form a first passivation layer. Compared with chemical deposition (including ALD and PECVD), it is necessary to control multiple process factors such as the deposition direction of the plasma and the flow rate of the process gas during the deposition process. The evaporation coating process only needs to heat and evaporate the first source material in the provided vacuum space to form a gaseous first source material to deposit the first passivation layer. It can be seen that it is only necessary to control the vacuum pressure intensity and the evaporation temperature, so that the above method has fewer process control factors, a simple process method, and saves time and effort.

[0041] At the same time, chemical deposition has good wrapping properties and can deposit thin films on different convex and concave surfaces. It is mainly used to plate passivation films on the surface of silicon wafers with uneven surfaces after texturing. When used to deposit the first passivation layer on the cross-section of crystalline silicon-based solar cell slices, it is also easy to cause the front and back sides of the crystalline silicon-based solar cell slices to be blocked by the first passivation layer, resulting in a reduction in the illuminated area. Physical deposition mainly deposits the first passivation layer in a manner similar to light incident deposition on the passivation surface due to the formed gaseous source material. The obscured area of ​​the crystalline silicon-based solar cell slice will not be plated with the first passivation layer.

[0042] S3. The evaporation annealing mechanism performs annealing treatment on the crystalline silicon-based cell slice group in the passivation unit after the first passivation layer deposition in a temperature environment of 100° C. to 350° C.

[0043] In this step, the interface structure between the first passivation layer and the surface to be passivated is changed by annealing to destroy Si dangling bonds, thereby reducing the probability of minority carriers on the surface to be passivated meeting and recombination on the surface, thereby reducing the surface recombination rate. The free hydrogen atoms in the evaporation annealing mechanism can occupy the vacancies of the dangling bonds on the surface to be passivated, reducing the interface state density on the surface to achieve the effect of reducing the surface recombination rate, thereby achieving a passivation effect to improve the photoelectric conversion efficiency of the passivated crystalline silicon-based cell slices.

[0044] The above-mentioned passivation repair method adopts physical deposition, namely evaporation coating and annealing treatment. Compared with the passivation repair process method of crystalline silicon-based solar cell slice sections by chemical deposition (including ALD and PECVD), it simplifies the process steps and corresponding equipment structure and reduces the control requirements of process factors, thereby achieving the purpose of improving the photoelectric conversion efficiency of passivated crystalline silicon-based solar cell slices. At the same time, it also avoids cumbersome processes, which is conducive to the automation and large-scale passivation production of crystalline silicon-based solar cell slices.

[0045] In addition, since the ALD and PECVD equipment need to be fed with special process gases due to their own processes, and the working environment of the battery string welding equipment needs to be isolated from the special process gases, the above-mentioned equipment cannot be in the same working environment, which makes it difficult for the passivation device containing the ALD and PECVD equipment to be directly connected with the battery string welding equipment. However, the physical deposition used in this application does not require the use of special gases, so the relevant equipment in the above method can also be directly connected with the battery string welding equipment, which is also conducive to improving the feeding efficiency of the battery string welding equipment.

[0046] On the other hand, the present application discloses a passivation device for implementing the above-mentioned passivation repair method. The disclosed passivation device includes a stacking mechanism, a sheet moving mechanism, a fixed tooling, a conveying mechanism and an evaporation annealing mechanism. The stacking mechanism is used to stack a plurality of crystalline silicon-based cell slices to form a crystalline silicon-based cell slice group. The sheet moving mechanism is used to transport the crystalline silicon-based cell slice group and place it in the fixed tooling. The conveying mechanism can carry and drive the fixed tooling to move to the evaporation annealing mechanism.

[0047] The cooperation between the above-mentioned structure stacking mechanism, sheet moving mechanism, fixing tooling, conveying mechanism and evaporation annealing mechanism realizes the above-mentioned passivation repair method, so as to realize the automation and large-scale passivation production of crystalline silicon-based battery slices. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0049] Figure 1 A schematic diagram of the structure of the passivation device disclosed in the embodiment of the present application;

[0050] In the figure: 100, passivation unit; 110, fixed tooling; 200, conveying mechanism; 210, conveying channel; 220, handling hand; 300, evaporation annealing mechanism; 400, lamination mechanism; 500, sheet moving mechanism. DETAILED DESCRIPTION

[0051] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly understood.

[0052] It should be noted that when an element is referred to as being "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time.

[0053] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0054] The present application discloses a passivation repair method for a crystalline silicon-based cell slice cross section. The disclosed passivation repair method comprises:

[0055] S1. Stack a plurality of crystalline silicon-based cell slices to form a crystalline silicon-based cell slice group, and make the cross-sections of the plurality of crystalline silicon-based cell slices coplanar to form a surface to be passivated, and place the crystalline silicon-based cell slice group in a fixed fixture 110 to form a passivation unit 100, wherein each surface to be passivated is exposed outside the corresponding fixed fixture 110.

[0056] In this step, the cross-sections of multiple crystalline silicon-based cell slices are coplanar to form a surface to be passivated, and the surface to be passivated is exposed outside the corresponding fixed tooling 110, thereby preventing the problem of the first passivation layer being wrapped around the cross-section end of any one of the multiple crystalline silicon-based cell slices when the first passivation layer is subsequently deposited on the crystalline silicon-based cell slice group. The crystalline silicon-based cell slices can be made of crystalline silicon cells, composite perovskite cells based on crystalline silicon, etc., and the present application does not impose any restrictions on this.

[0057] S2. Provide a conveying mechanism 200 to convey the passivation unit 100 to the evaporation annealing mechanism 300. The evaporation annealing mechanism 300 is provided with a first source material. Under vacuum conditions and a temperature environment of 20°C to 300°C, the evaporation annealing mechanism 300 heats and evaporates the first source material to form a gaseous first source material. The gaseous first source material is deposited on the surface to be passivated in the passivation unit 100 to form a first passivation layer.

[0058] In this step, by means of physical deposition (i.e., evaporation coating process), the first source material is heated and evaporated to form a gaseous first source material, and the gaseous first source material is deposited on the surface to be passivated in the passivation unit 100 to form a first passivation layer. Compared with chemical deposition (including ALD method and PECVD method), it is necessary to control the deposition direction of the plasma, the flow rate of the process gas, and other process factors during the deposition process. The evaporation coating process only needs to heat and evaporate the first source material in the provided vacuum space to form a gaseous first source material to deposit the first passivation layer. It can be seen that it is only necessary to control the pressure intensity and evaporation temperature of the vacuum pump, so that the above method has fewer process control factors, a simple process method, and saves time and effort. Among them, the first source material can be aluminum oxide, titanium oxide, etc., and this application does not impose any restrictions on this.

[0059] At the same time, chemical deposition has good wrapping properties and can deposit thin films on different convex and concave surfaces. It is mainly used to plate passivation films on the surface of silicon wafers with uneven surfaces after texturing. When used to deposit the first passivation layer on the cross-section of crystalline silicon-based solar cell slices, it is also easy to cause the front and back sides of the crystalline silicon-based solar cell slices to be blocked by the first passivation layer, resulting in a reduction in the illuminated area. Physical deposition mainly deposits the first passivation layer in a manner similar to light incident deposition on the passivation surface due to the formed gaseous source material. The obscured area of ​​the crystalline silicon-based solar cell slice will not be plated with the first passivation layer.

[0060] S3, the evaporation annealing mechanism 300 performs annealing treatment on the crystalline silicon-based cell slice group in the passivation unit 100 after the first passivation layer deposition is completed in a temperature environment of 100° C. to 350° C.

[0061] In this step, annealing treatment is performed to change the interface structure between the first passivation layer and the surface to be passivated to destroy Si dangling bonds, thereby reducing the probability of minority carriers on the surface to be passivated meeting and recombination on the surface, thereby reducing the surface recombination rate. The free hydrogen atoms in the evaporation annealing mechanism 300 can occupy the vacancies of the dangling bonds on the surface to be passivated, reducing the interface state density on the surface to achieve the effect of reducing the surface recombination rate, thereby achieving a passivation effect to improve the photoelectric conversion efficiency of the passivated crystalline silicon-based cell slices.

[0062] The above-mentioned passivation repair method adopts physical deposition, namely evaporation coating and annealing treatment. Compared with the passivation repair process method of crystalline silicon-based solar cell slice sections by chemical deposition (including ALD and PECVD), it simplifies the process steps and corresponding equipment structure and reduces the control requirements of process factors, thereby achieving the purpose of improving the photoelectric conversion efficiency of passivated crystalline silicon-based solar cell slices. At the same time, it also avoids cumbersome processes, which is conducive to the automation and large-scale passivation production of crystalline silicon-based solar cell slices.

[0063] In addition, since the ALD and PECVD equipment need to be fed with special process gases due to their own processes, and the working environment of the battery string welding equipment needs to be isolated from the special process gases, the above-mentioned equipment cannot be in the same working environment, which makes it difficult for the passivation device containing the ALD and PECVD equipment to be directly connected with the battery string welding equipment. However, the physical deposition used in this application does not require the use of special gases, so the relevant equipment in the above method can also be directly connected with the battery string welding equipment, which is also conducive to improving the feeding efficiency of the battery string welding equipment.

[0064] In a first optional solution, in step S2, the following steps may be included:

[0065] S21, the evaporation annealing mechanism 300 includes an evaporation cavity and an annealing cavity, the evaporation cavity and the annealing cavity are not connected, and the conveying mechanism 200 conveys the passivation unit 100 to the evaporation cavity to deposit a first passivation layer;

[0066] In this step, two continuous processing stations are formed by setting up a non-interconnected evaporation chamber and an annealing chamber, so as to achieve continuous operation of the first passivation layer deposition and annealing treatment of the passivation unit 100, thereby further improving the passivation efficiency.

[0067] S22 , the conveying mechanism 200 conveys the passivation unit 100 on which the first passivation layer deposition is completed to the annealing chamber.

[0068] In a second optional scheme, the evaporation annealing mechanism 300 may be provided with a process chamber, and the passivation unit 100 may sequentially complete the first passivation layer deposition and annealing treatment in the process chamber, that is, the first passivation layer deposition process and the annealing treatment process are both completed in the process chamber. By sequentially completing the first passivation layer deposition and annealing treatment of the passivation unit 100 in the process chamber, it not only avoids the need for multiple transfers of the passivation unit 100, but also is conducive to the integrated design of the evaporation annealing mechanism 300.

[0069] In a third optional solution, in step S2, the following steps may be included:

[0070] The surface to be passivated in the passivation unit 100 is transported to the evaporation annealing mechanism 300 after cleaning and drying, or the transport mechanism 200 transports the passivation unit 100 to the evaporation annealing mechanism 300, and the evaporation annealing mechanism 300 is preheated and vacuumed at the same time, and the preheating temperature is 50-100°C;

[0071] When the crystalline silicon-based solar cell is diced to form crystalline silicon-based solar cell slices, water stains will remain on the cross-section of the crystalline silicon-based solar cell slices. In this step, the cleanliness of the surface to be passivated in the passivation unit 100 is improved by cleaning and drying. Of course, when preheating directly in the evaporation annealing mechanism 300, the preheating temperature is 50~150℃, and the water stains on the surface to be passivated will also evaporate due to the heat, thereby ensuring the deposition effect of the first passivation layer. Of course, the higher the preheating temperature, the faster the water stain cleaning efficiency.

[0072] In a further technical solution, in a first optional solution, in step S2, the method of heating and evaporating the first source material to form a gaseous first source material may include:

[0073] The evaporation annealing mechanism 300 is provided with an electron beam gun, which sprays electron beams to bombard the first source material to form a gaseous first source material.

[0074] In this step, the electron beam gun is characterized by being able to obtain extremely high energy density, up to 109w / cm2, and a heating temperature of 3000-6000℃. The electron beam gun can accurately bombard the first source material with electron beams by using the cooperation of electromagnetic fields, which not only makes it melt and evaporate quickly and then deposit on the cross section of the crystalline silicon-based cell slice, but also improves the purity of the gaseous first source material. This is conducive to the rapid deposition and high purity of the first passivation layer, thereby ensuring the passivation effect.

[0075] In a second optional solution, in step S2, the method of heating and evaporating the first source material to form a gaseous first source material may include:

[0076] The evaporation annealing mechanism 300 is provided with a resistance heating element, which carries the first source material and heats the first source material to form a gaseous first source material.

[0077] In a third optional solution, in step S2, the method of heating and evaporating the first source material to form a gaseous first source material may include:

[0078] The evaporation annealing mechanism 300 is provided with a laser emitting component, which emits laser to heat the first source material to form a gaseous first source material.

[0079] In a fourth optional solution, the step S2 may include:

[0080] The evaporation annealing mechanism 300 is also provided with a second source material. After the first passivation layer is deposited on the surface to be passivated, the evaporation annealing mechanism 300 heats and evaporates the second source material to form a gaseous second source material, and the gaseous second source material is used to deposit a second passivation layer on the first passivation layer on the surface to be passivated.

[0081] In this step, a second passivation layer is deposited on the first passivation layer to protect the first passivation layer, thereby extending the service life of the first passivation layer and increasing the storage time of crystalline silicon-based cell slices. The second source material can be aluminum nitride, silicon oxide, etc., and this application does not impose any restrictions on this.

[0082] In a further technical solution, the evaporation annealing mechanism 300 is further provided with a second source material. After the first passivation layer is deposited on the surface to be passivated, the evaporation annealing mechanism 300 heats and evaporates the second source material to form a gaseous second source material. The step of depositing the second passivation layer on the first passivation layer on the surface to be passivated with the gaseous second source material may include:

[0083] The evaporation annealing mechanism 300 includes a first evaporation chamber, a second evaporation chamber and an annealing chamber which are not interconnected. The first evaporation chamber is provided with a first source material, and the second evaporation chamber is provided with a second source material. The conveying mechanism 200 conveys the passivation unit 100 which has completed the deposition of the first passivation layer to the second evaporation chamber. Under vacuum conditions and a temperature environment of 20° C. to 300° C., the second source material is heated and evaporated to form a gaseous second source material. The gaseous second source material is deposited on the first passivation layer on the surface to be passivated to form a second passivation layer.

[0084] In this step, three consecutive workstations are formed by setting up a first evaporation chamber, a second evaporation chamber and an annealing chamber, and the first passivation layer, the second passivation layer and the annealing treatment are sequentially deposited on the surface to be passivated of the passivation unit 100, thereby facilitating the automated continuous production of the passivation unit 100.

[0085] The conveying mechanism 200 conveys the passivation unit 100 on which the second passivation layer deposition is completed to the annealing chamber.

[0086] In a fifth optional solution, the step S2 may include:

[0087] The evaporation annealing mechanism 300 is also provided with a second source material. Under vacuum conditions and a temperature environment of 20° C. to 300° C., the evaporation annealing mechanism 300 heats and evaporates the second source material to form a gaseous second source material, and the gaseous second source material is deposited on the surface to be passivated to form a second passivation layer.

[0088] After the second passivation layer is deposited on the surface to be passivated, the evaporation annealing mechanism 300 heats and evaporates the first source material to form a gaseous first source material, and the gaseous first source material is used to deposit the first passivation layer on the second passivation layer.

[0089] In this step, the gaseous first source material is deposited on the second passivation layer on the surface to be passivated. The gaseous first source material is in a free molecular or ionic state in the vapor deposition state. During the deposition process, the gaseous first source material can be doped in the second passivation layer, and part of it can penetrate through the second passivation layer and penetrate into the surface to be passivated, thereby reducing the probability of minority carriers on the surface to be passivated meeting and recombination on the surface, thereby reducing the surface recombination velocity, and thus achieving a better passivation effect. The second source material can be silicon oxide, titanium oxide, etc., and this application does not impose any restrictions on this.

[0090] Of course, a third source material may also be provided in the evaporation annealing mechanism 300. After the first passivation layer is deposited on the passivation surface, the evaporation annealing mechanism 300 heats and evaporates the third source material to form a gaseous third source material, and the gaseous third source material is deposited as a protective layer on the first passivation layer.

[0091] The third source material may be aluminum nitride, silicon oxide, etc., and this application does not impose any limitation on this.

[0092] In the embodiment of the present application, step S2 may include:

[0093] The passivation unit 100 is located in the evaporation annealing mechanism 300, and the angle formed by the direction of the passivation surface of the passivation unit 100 and the gravity direction is 0~90°. The passivation unit 100 is located above the first source material. While the evaporation annealing mechanism 300 deposits the first passivation layer on the passivation unit 100, the passivation unit 100 rotates horizontally.

[0094] In this step, the passivation unit 100 is located above the first source material, and the gaseous first source material formed by the heating of the first source material will rise to form a mist. The angle formed by the orientation direction of the surface to be passivated in the passivation unit 100 is 0~90°, and of course it can be 5°, 10°, 15°, 30°, 60° and 90°, etc., to ensure that the surface to be passivated can be more comprehensively deposited with the first passivation layer, thereby improving the deposition area and deposition effect of the first passivation layer. The passivation unit 100 rotates horizontally so that the surface to be passivated also rotates, and each position in the surface to be passivated can contact the gaseous first source material of different regional concentrations, so that the first passivation layer deposited on the surface to be passivated can be more uniform.

[0095] In the embodiment of the present application, the conveying mechanism 200 can convey multiple passivation units 100 to the evaporation annealing mechanism 300 to complete the first passivation layer deposition, and the evaporation annealing mechanism 300 can sequentially complete the deposition of the first passivation layer and annealing treatment of multiple passivation units 100, thereby further improving the passivation efficiency.

[0096] In an embodiment of the present application, in step S2, the deposition rate of the gaseous first source material to deposit the first passivation layer on the passivation surface can be 0.1~20Å / s.

[0097] In this step, the deposition rate is 0.1~20Å / s, and the time for the gaseous first source material to deposit the first passivation layer on the passivation surface in the passivation unit 100 is basically 60~400s. Compared with the chemical deposition in the prior art, the process time for depositing the first thin film by the ALD method is 200~2000s, and the process time for depositing the second thin film by the PECVD method is 200~2000s. The coating time of the above steps is shorter, which is beneficial to improving the passivation efficiency of depositing the first passivation layer on the passivation surface.

[0098] Experimental Example 1 is a method of slicing multiple crystalline silicon-based solar cells obtained by laser non-destructive method.

[0099] Experimental Example 2 is a plurality of crystalline silicon-based cell slices obtained by laser non-destructive method. First, a plurality of crystalline silicon-based cell slices are stacked to form a crystalline silicon-based cell slice group, and the cross-sections of the plurality of crystalline silicon-based cell slices are coplanar to form a surface to be passivated. Then, the crystalline silicon-based cell slice group is placed in a fixed tool 110 to form a passivation unit 100, wherein the surface to be passivated of the crystalline silicon-based cell slice group is exposed outside the fixed tool 110; finally, the passivation unit 100 is transported to the evaporation annealing mechanism 300, and under vacuum conditions and a temperature environment of 20°C to 300°C, the evaporation annealing mechanism 300 heats and evaporates the first source material to form a gaseous first source material, and the gaseous first source material deposits a first passivation layer on the surface to be passivated in the passivation unit 100, to obtain a group of crystalline silicon-based cell slice groups.

[0100] Experimental Example 3 is a plurality of crystalline silicon-based cell slices obtained by laser non-destructive method. First, a plurality of crystalline silicon-based cell slices are stacked to form a crystalline silicon-based cell slice group. The cross sections of the plurality of crystalline silicon-based cell slices are coplanar to form a surface to be passivated. The crystalline silicon-based cell slice group is correspondingly placed in a fixed fixture 110 to form a passivation unit 100, wherein the surface to be passivated of the crystalline silicon-based cell slice group is exposed outside the fixed fixture 110; then, the passivation unit 100 is transported to the evaporation annealing mechanism. In 300, under vacuum conditions and a temperature environment of 20°C to 300°C, the evaporation annealing mechanism 300 heats and evaporates the first source material to form a gaseous first source material, and the gaseous first source material is deposited on the surface to be passivated in the passivation unit 100 to form a first passivation layer; finally, the evaporation annealing mechanism 300 anneals the crystalline silicon-based battery cell segment group in the passivation unit 100 on which the first passivation layer has been deposited in a temperature environment of 100°C to 350°C to obtain a group of crystalline silicon-based battery cell segments.

[0101] Comparative Example 1 is a plurality of crystalline silicon-based cell slices obtained by laser non-destructive method. First, a plurality of crystalline silicon-based cell slices are stacked to form a crystalline silicon-based cell slice group. The cross-sections of the plurality of crystalline silicon-based cell slices are coplanar to form a passivation surface. The crystalline silicon-based cell slice group is correspondingly placed in a fixed tool 110 to form a passivation unit 100, wherein the surface to be passivated of the crystalline silicon-based cell slice group is exposed outside the fixed tool 110; then, the passivation unit 100 is transported to an ALD deposition device to deposit a first layer of passivation film on the surface to be passivated; then, the passivation unit 100 is transported to a PECVD reaction device to deposit a second layer of protective film; finally, the passivation unit 100 is transported to a light injection annealing furnace for annealing treatment to obtain a group of crystalline silicon-based cell slice groups.

[0102] Comparative Example 1 and the crystalline silicon-based cell slices obtained by laser non-destructive method using 182mm×182mm crystalline silicon-based cell slices, the performance of 3 crystalline silicon-based cell slices were randomly selected from the crystalline silicon-based cell slice groups obtained in Comparative Example 1 and Experimental Examples 1 to 3 for characterization.

[0103] The test method is to use a halm IV tester to test each group of crystalline silicon-based cell slices in Experimental Examples 1 to 3 under standard test conditions of 25±2℃ and a light intensity range of 1000±50W / m2. The test results are shown in the following table:

[0104]

[0105] In the above table, Eff refers to the conversion efficiency, Voc is the open circuit voltage, Isc is the short circuit current, P max is the peak power, Im is the operating current, and Vm is the peak voltage.

[0106] It can be seen from the above table that by comparing the average conversion efficiency of the three groups in Experimental Example 2 with the average conversion efficiency of the three groups in Experimental Example 1, it can be seen that the conversion efficiency of the crystalline silicon-based cell slices obtained by only using the evaporation annealing mechanism 300 to complete the deposition of the first passivation layer under vacuum conditions and a temperature environment of 20°C ~ 300°C is improved by about 0.12% compared with the crystalline silicon-based cell slices obtained only by laser non-destructive method.

[0107] By comparing the average conversion efficiency of the three groups in Experimental Example 3 with the average conversion efficiency of the three groups in Experimental Example 1, it can be seen that the crystalline silicon-based cell slices obtained by annealing the crystalline silicon-based cell slices after the deposition of the first passivation layer by the evaporation annealing mechanism 300 under vacuum conditions and a temperature environment of 20°C to 300°C, and then annealing the crystalline silicon-based cell slices after the deposition of the first passivation layer under a temperature environment of 100°C to 350°C, have a conversion efficiency improved by about 0.19% compared with the crystalline silicon-based cell slices obtained only by a laser non-destructive method.

[0108] By comparing the average conversion efficiency of the three groups in Experimental Example 3 with the average conversion efficiency of the three groups in Experimental Example 2, it can be seen that the conversion efficiency of the crystalline silicon-based cell slices obtained by the evaporation coating and annealing processes in sequence is improved by about 0.07% compared with the crystalline silicon-based cell slices obtained only by the evaporation coating process.

[0109] By comparing the average conversion efficiency of the three groups in Comparative Example 1 with the average conversion efficiency of the three groups in Experimental Example 1, it can be seen that the first passivation film and the second protective film are deposited in sequence by ALD deposition equipment and PECVD reaction equipment, and then the crystalline silicon-based cell slices are obtained by annealing in a light injection annealing furnace. Compared with the crystalline silicon-based cell slices obtained only by laser non-destructive method, the conversion efficiency is improved by about 0.18%.

[0110] By comparing the average conversion efficiency of the three groups in Comparative Example 1 with the average conversion efficiency of the three groups in Experimental Example 3, the conversion efficiencies are almost the same. It can be seen that the passivation effect achieved by physical deposition is basically consistent with the passivation effect of chemical deposition, and the process steps of physical deposition are simpler. At the same time, it is found that chemical deposition is prone to wrap-around plating, mainly because arc ion plating has good wrap-around properties and can deposit thin films on polymer substrates with different convex and concave surfaces. It is particularly suitable for coating samples with uneven surfaces, which can easily lead to the front and back sides of the crystalline silicon-based cell slices being blocked by the first passivation layer. The illumination area is reduced. The physical deposition is mainly because the formed gaseous source material presents a similar light incident deposition method to the surface to be passivated, and the obscured area is not easily coated with the first passivation layer.

[0111] It can be seen that the passivation repair method disclosed in the above-mentioned application can be used to repair the cross-section of crystalline silicon-based solar cell slices and improve the conversion efficiency. At the same time, compared with the chemical deposition method, while achieving the same efficiency improvement purpose, the passivation repair method disclosed in the application has simple process steps, fewer process control factors, saves time and labor, and is conducive to the large-scale production of cross-section passivation of crystalline silicon-based solar cell slices.

[0112] like Figure 1 As shown, the present application also discloses a passivation device for implementing the above-mentioned passivation repair method. The disclosed passivation device includes a stacking mechanism 400, a sheet moving mechanism 500, a fixed tool 110, a conveying mechanism 200 and a vapor deposition annealing mechanism 300. The stacking mechanism 400 is used to stack a plurality of crystalline silicon-based cell slices to form a crystalline silicon-based cell slice group. The sheet moving mechanism 500 is used to transport the crystalline silicon-based cell slice group and place it in the fixed tool 110. The conveying mechanism 200 can carry and drive the fixed tool 110 to move to the vapor deposition annealing mechanism 300.

[0113] The above structure realizes the above passivation repair method through the cooperation between the stacking mechanism 400, the sheet moving mechanism 500, the fixing tool 110, the conveying mechanism 200 and the evaporation annealing mechanism 300, so as to realize the automated slicing and large-scale passivation production of crystalline silicon-based solar cells.

[0114] In addition, the stacking mechanism 400 can be a stacking storage arm that can be stepped and raised, and completes the stacking of multiple crystalline silicon-based cell slices by raising and lowering the thickness of a crystalline silicon-based cell slice. Alternatively, the stacking mechanism 400 may include a belt conveyor, a grabbing robot and a stacking table. The belt conveyor carries multiple array-arranged crystalline silicon-based cell slices, and the grabbing robot can grab the crystalline silicon-based cell slices and stack them on the stacking table. This application does not impose any restrictions on this.

[0115] In an embodiment of the present application, the fixing tool 110 may include a cavity with an opening and a fastener. Specifically, the crystalline silicon-based cell slice group can be placed in the cavity. The cross-sections of multiple crystalline silicon-based cell slices in the crystalline silicon-based cell slice group are coplanar and exposed at the opening or flush with the end face of the opening. The fastener is arranged in the cavity. The fastener is used to fix the crystalline silicon-based cell slice group in the cavity, so as to avoid relative displacement of the multiple crystalline silicon-based cell slices, which may cause at least one of the multiple crystalline silicon-based cell slices to have a plating bypass problem during the deposition of the first passivation layer.

[0116] In an embodiment of the present application, the conveying mechanism 200 may include a conveying channel 210 and a handling hand 220. Specifically, the conveying channel 210 may carry and drive the passivation unit 100 to move to the first position, and the handling hand 220 may carry the passivation unit 100 at the first position to the evaporation annealing mechanism 300.

[0117] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A passivation repair method for a crystalline silicon-based cell section, characterized in that: include: S1, stacking a plurality of crystalline silicon-based cell slices to form a crystalline silicon-based cell slice group, and making the cross sections of the plurality of crystalline silicon-based cell slices coplanar to form a surface to be passivated, and placing the crystalline silicon-based cell slice group in a fixed fixture (110) to form a passivation unit (100), wherein each surface to be passivated is exposed outside the fixed fixture (110); S2. Provide a conveying mechanism (200) to convey the passivation unit (100) to an evaporation annealing mechanism (300), wherein a first source material is arranged in the evaporation annealing mechanism (300), and under vacuum conditions and a temperature environment of 20°C to 300°C, the evaporation annealing mechanism (300) heats and evaporates the first source material to form a gaseous first source material, and the gaseous first source material is deposited on the surface to be passivated in the passivation unit (100) as a first passivation layer, the passivation unit (100) is located in the evaporation annealing mechanism (300), the angle formed by the direction of the surface to be passivated of the passivation unit (100) and the gravity direction is 0° to 90°, the passivation unit (100) is located above the first source material, and while the evaporation annealing mechanism (300) deposits the first passivation layer on the passivation unit (100), the passivation unit (100) rotates horizontally; S3, the evaporation annealing mechanism (300) performs annealing treatment on the crystalline silicon-based solar cell slice group in the passivation unit (100) on which the first passivation layer deposition has been completed under a temperature environment of 100° C. to 350° C.

2. The passivation repair method for a crystalline silicon-based cell section according to claim 1, characterized in that: In the step S2, it includes: S21, the evaporation annealing mechanism (300) comprises an evaporation cavity and an annealing cavity, the evaporation cavity is not connected to the annealing cavity, and the conveying mechanism (200) conveys the passivation unit (100) to the evaporation cavity to deposit the first passivation layer; S22, the conveying mechanism (200) conveys the passivation unit (100) on which the first passivation layer deposition is completed to the annealing chamber.

3. The passivation repair method for a crystalline silicon-based cell section according to claim 1, characterized in that: The evaporation annealing mechanism (300) is provided with a process chamber, and the passivation unit (100) sequentially completes the first passivation layer deposition and the annealing treatment in the process chamber.

4. The passivation repair method for a crystalline silicon-based cell section according to claim 1, characterized in that: In the step S2, it includes: The surface to be passivated in the passivation unit (100) is transported to the evaporation annealing mechanism (300) after cleaning and drying, or the transport mechanism (200) transports the passivation unit (100) to the evaporation annealing mechanism (300), and the evaporation annealing mechanism (300) is preheated and evacuated at the same time, and the preheating temperature is 50-150°C.

5. The passivation repair method for a crystalline silicon-based cell section according to claim 1, characterized in that: In the step S2, the method of heating and evaporating the first source material to form the gaseous first source material includes: The evaporation annealing mechanism (300) is provided with an electron beam gun, which sprays an electron beam to bombard the first source material to form the gaseous first source material.

6. The passivation repair method for a crystalline silicon-based cell section according to claim 1, characterized in that: In the step S2, the method of heating and evaporating the first source material to form the gaseous first source material includes: The evaporation annealing mechanism (300) is provided with a resistance heating element, the resistance heating element carries the first source material, and the resistance heating element heats the first source material to form the gaseous first source material.

7. The passivation repair method for a crystalline silicon-based cell section according to claim 1, characterized in that: In the step S2, the method of heating and evaporating the first source material to form the gaseous first source material includes: The evaporation annealing mechanism (300) is provided with a laser emitting component, and the laser emitting component emits laser to heat the first source material to form the gaseous first source material.

8. The passivation repair method for a crystalline silicon-based cell section according to claim 1, characterized in that: In the step S2, it includes: The evaporation annealing mechanism (300) is also provided with a second source material. After the first passivation layer is deposited on the surface to be passivated, the evaporation annealing mechanism (300) heats and evaporates the second source material to form a gaseous second source material. The gaseous second source material is used to deposit a second passivation layer on the first passivation layer on the surface to be passivated.

9. The passivation repair method for a crystalline silicon-based cell section according to claim 8, characterized in that: The evaporation annealing mechanism (300) is further provided with the second source material. After the first passivation layer is deposited on the surface to be passivated, the evaporation annealing mechanism (300) heats and evaporates the second source material to form the gaseous second source material. The step of depositing the second passivation layer on the first passivation layer on the surface to be passivated using the gaseous second source material comprises: The evaporation annealing mechanism (300) comprises a first evaporation cavity, a second evaporation cavity and an annealing cavity which are not interconnected, the first evaporation cavity is provided with the first source material, the second evaporation cavity is provided with the second source material, the conveying mechanism (200) conveys the passivation unit (100) after the first passivation layer deposition is completed to the second evaporation cavity, under vacuum conditions and a temperature environment of 20°C to 300°C, the second source material is heated and evaporated to form the gaseous second source material, and the gaseous second source material is deposited on the first passivation layer on the surface to be passivated to form the second passivation layer; The transport mechanism (200) transports the passivation unit (100) on which the second passivation layer deposition is completed to the annealing chamber.

10. The passivation repair method for a crystalline silicon-based cell section according to claim 1, characterized in that: In the step S2, it includes: The evaporation annealing mechanism (300) is also provided with a second source material. Under vacuum conditions and a temperature environment of 20°C to 300°C, the evaporation annealing mechanism (300) heats and evaporates the second source material to form a gaseous second source material. The gaseous second source material is deposited on the surface to be passivated to form a second passivation layer. After the second passivation layer is deposited on the surface to be passivated, the evaporation annealing mechanism (300) heats and evaporates the first source material to form the gaseous first source material, and the gaseous first source material is used to deposit the first passivation layer on the second passivation layer.

11. The passivation repair method for a crystalline silicon-based cell section according to claim 1, characterized in that: The conveying mechanism (200) can convey the plurality of the passivation units (100) to the evaporation annealing mechanism (300) to complete the deposition of the first passivation layer, and the evaporation annealing mechanism (300) can sequentially complete the deposition of the first passivation layer and annealing treatment of the plurality of the passivation units (100).

12. The passivation repair method for a crystalline silicon-based cell section according to claim 1, characterized in that: In the step S2, the deposition rate of the gaseous first source material on the surface to be passivated to deposit the first passivation layer is 0.1-20Å / s.

13. A passivation device for implementing the passivation repair method according to any one of claims 1 to 12, characterized in that: The invention comprises a stacking mechanism (400), a sheet moving mechanism (500), the fixed tool (110), the conveying mechanism (200) and the evaporation annealing mechanism (300); the stacking mechanism (400) is used for stacking a plurality of the crystalline silicon-based solar cell sheets to form a crystalline silicon-based solar cell sheet group; the sheet moving mechanism (500) is used for moving the crystalline silicon-based solar cell sheet group and placing it in the fixed tool (110) to form the passivation unit (100); and the conveying mechanism (200) can carry and drive the passivation unit (100) to move to the evaporation annealing mechanism (300).

14. The passivation device according to claim 13, characterized in that The fixing tool (110) comprises a cavity with an opening and a fastener, the crystalline silicon-based cell slice group can be placed in the cavity, the cross-sections of the plurality of crystalline silicon-based cell slices in the crystalline silicon-based cell slice group are coplanar and exposed at the opening or flush with the end surface of the opening, and the fastener is arranged in the cavity, and is used to fix the crystalline silicon-based cell slice group in the cavity.

15. The passivation device according to claim 13, characterized in that: The conveying mechanism (200) comprises a conveying channel (210) and a handling hand (220); the conveying channel (210) can carry and drive the passivation unit (100) to move to the discharge end of the conveying channel (210); and the handling hand (220) carries the passivation unit (100) at the discharge end to the evaporation annealing mechanism (300).

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