Thin film solar cell module interconnection structure and preparation method thereof

Abstract

The invention relates to a thin film solar cell module interconnection structure and a preparation method thereof. The preparation method comprises the following steps: 1) selecting a substrate to deposit a first electrode layer; (2) forming a P1 scribing line; 3) depositing a device functional layer; 4) forming a P2 scribing line; 5) depositing a second electrode layer; and (6) forming a P3 lineation line. On one hand, on the premise that the width of a dead zone is reduced, photon-generated carriers of a device function layer corresponding to P3 lineation have a certain probability under the drifting effect and can be collected, the photoelectric conversion performance of the assembly is further improved, the device function layer can form absorption, conductive channels between adjacent sub-cells are prevented from being broken, and the photoelectric conversion efficiency of the assembly is improved. Series resistance is reduced; on the other hand, on the basis of the formed paddle-tumbler, and the paddle-tumbler and the groove are communicated or separated by the second electrode layer, not only can the scratch edge be prevented from tilting to cause craters, but also the damage of the device layer can be controlled, and lattice defects near a dead zone can be eliminated, so that the open-circuit voltage and the fill factor can be improved.

Description

Technical Field

[0001] The present invention belongs to the field of solar cells, and particularly relates to an interconnection structure for thin-film solar cell modules, and also relates to a preparation method for the interconnection structure of thin-film solar cell modules. Background Art

[0002] Currently, for large-area thin-film solar cell modules, three scribing and interconnection processes are basically required to meet the actual use requirements. Briefly, generally, a large-area cell is divided into several sub-cell units by laser scribing in a thin-film solar cell module, and then interconnected. The specific process (combined with Figure 1 shown) is as follows: First, the first electrode layer 1' on the substrate 0' is scribed into several small sections to form P1 scribing; then, a P / N-type functional layer 2', an intrinsic absorption layer 3', and an N / P-type functional layer 4' are deposited to form a device layer for photoelectric conversion; then, on one side of the P1 scribing at a distance as small as possible, the device layer is scribed in parallel the same number of times to form P2 scribing; finally, after depositing the second electrode layer 5', on one side of the P2 scribing at a distance as small as possible, the device layer is scribed in parallel the same number of times to form P3 scribing. In this way, a series structure of several sub-cells is formed in the entire large-area cell. However, this scribing and segmentation interconnection method has the following problems: 1) For each sub-cell, a non-power generation area, also known as a dead zone, is formed between the P1 scribing and the P3 scribing. Among them, in the device area between P2 and P3, due to being blocked by P3, it is in a short-circuit state. As the Figure 1 dotted line part in is the invalid area. Therefore, the existence of this dead zone directly reduces the effective power generation area, reduces the number of photo-generated carriers, causes a decrease in the short-circuit current (Isc), and at the same time, lattice defects or impurities near the dead zone form recombination centers, accelerating the recombination of electron-hole pairs, and reducing the open-circuit voltage (Voc) and fill factor (FF); 2) The P3 scribing used completely removes the absorption layer. That is, the P3 scribing should only isolate the back electrode layer. If the absorption layer is over-removed, it may cause the conductive channel between adjacent sub-cells to break, destroy the series structure of the sub-cells, significantly increase the series resistance (Rs), reduce the fill factor (FF) and efficiency. At the same time, the dead zone range includes the entire area between P1 and P3 (generally, the width of the dead zone is 100 - 200 μm). Therefore, the overall photoelectric conversion performance of the module is low. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide an improved interconnection structure for thin-film solar cell modules.

[0004] At the same time, it also relates to a preparation method for the interconnection structure of thin-film solar cell modules.

[0005] To solve the above technical problems, the technical solution adopted by the present invention is as follows: A preparation method for an interconnection structure of a thin-film solar cell module, which includes the following steps: 1) Select a substrate and deposit a first electrode layer on the substrate; 2) Scratch a P1 scribeline on the first electrode layer, and the scratching depth is the thickness of the first electrode layer; 3) Deposit a P / N type functional layer, an intrinsic absorption layer, and an N / P type functional layer on the first electrode layer and the substrate in sequence. The P / N type functional layer fills the scribed area, and the surface of the P / N type functional layer is flat; 4) Taking the P1 scribeline as a parallel reference, form a P2 scribeline that is recessed from the P / N type functional layer to the first electrode layer near the P1 scribeline, and the scratching depth is the sum of the thicknesses of the N / P type functional layer, the intrinsic absorption layer, and the P / N type functional layer; 5) Deposit a second electrode layer, where part of the second electrode layer is formed on the N / P type functional layer, part is formed on the corresponding groove walls of the N / P type functional layer, the intrinsic absorption layer, and the P / N type functional layer in the groove of the P2 scribeline, and the remaining part is formed on the first electrode layer. And the second electrode layer located within the P2 scribeline forms a groove, and the width of the groove is smaller than the width of the P2 scribeline; 6) Taking the P2 scribeline as a parallel reference, scratch a P3 scribeline from the second electrode layer to the N / P type functional layer near the P2 scribeline, and the depth of the P3 scribeline is the thickness of the second electrode layer. The sum of the width of the P1 scribeline, the width of the P2 scribeline, and the interval width between the P1 scribeline and the P2 scribeline is equal to the dead zone width; the P3 scribeline forms a groove, and the groove is either connected to or separated by the second electrode layer from the groove.

[0006] In some specific embodiments, the substrate material is inorganic non-metal, metal or polymer. Inorganic non-metals include rigid glass and flexible glass; metals include stainless steel, aluminum alloy and titanium; and / or, polymers include polyethylene terephthalate, polyethylene naphthalate, polyimide, parylene and polycarbonate. In short, the substrate material includes but is not limited to inorganic non-metals, metals or polymers, where inorganic non-metals such as rigid glass, ultra-thin flexible glass; metals such as stainless steel (SS), aluminum alloy (Al), titanium (Ti); polymers such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), parylene, polycarbonate (PC), etc.

[0007] According to a specific implementation and preferred aspect of the present invention, in step 1), the material of the first electrode layer is a transparent conductive oxide. Specifically, the deposition method of the first electrode layer includes any one or a combination of at least two of vacuum evaporation, magnetron sputtering, reactive plasma deposition, and chemical vapor deposition.

[0008] Preferably, the thickness of the first electrode layer is 10 - 1000 nm.

[0009] In some specific embodiments, the material of the first electrode layer includes any one or a combination of at least two of fluorine-doped tin oxide, indium tin oxide, indium zinc oxide, aluminum-doped zinc oxide, indium tungsten oxide, tin titanium indium oxide, boron-doped zinc oxide, and cerium-doped indium oxide.

[0010] Alternatively, the material of the first electrode layer is a metal oxide, and the conductive metals in the metal oxide include one or a combination of at least two of copper, silver, gold, iron, aluminum, tungsten, molybdenum, chromium, nickel, tantalum, vanadium, titanium, and manganese.

[0011] In short, the material of the first electrode layer can be a transparent conductive oxide (TCO) including, but not limited to, any one or a combination of at least two of FTO (fluorine-doped tin oxide), ITO (indium tin oxide), IZO (indium zinc oxide), AZO (aluminum-doped zinc oxide), IWO (indium tungsten oxide), ITIO (tin titanium indium oxide), BZO (boron-doped zinc oxide), or ICO (cerium-doped indium oxide), or can be a conductive metal including, but not limited to, any one or a combination of at least two of high-conductivity metals and alloys such as copper, silver, gold, iron, aluminum, tungsten, molybdenum, chromium, nickel, tantalum, vanadium, titanium, and manganese.

[0012] According to another specific implementation and preferred aspect of the present invention, in step 2), nanosecond infrared or picosecond infrared or nanosecond ultraviolet or picosecond ultraviolet laser is used to scribe the P1 scribing line, where the number of P1 scribing lines is any integer greater than 1, and the numbers of P2 scribing lines and P3 scribing lines match the number of P1 scribing lines and are arranged in one-to-one correspondence. That is, each sub-cell unit forms a set of P1 scribing lines, P2 scribing lines, and P3 scribing lines.

[0013] Preferably, the width of the P1 scribing line is 20 - 50 μm; the wavelength of the infrared laser used is 1064 ± 106.4 nm, the wavelength of the green laser is 532 ± 53.2 nm, and the wavelength of the ultraviolet laser is 355 ± 35.5 nm.

[0014] According to another specific implementation and preferred aspect of the present invention, in step 3), the P / N-type functional layer, the intrinsic absorption layer, and the N / P-type functional layer form a device layer for photoelectric conversion, and the device layer is a combination of one or at least two of amorphous silicon, perovskite, copper indium gallium selenide, cadmium telluride, and gallium arsenide.

[0015] According to yet another specific implementation and preferred aspect of the present invention, in step 4), a mechanical scribing or nanosecond infrared or picosecond infrared or nanosecond green or picosecond green or nanosecond ultraviolet or picosecond ultraviolet laser is used to scribe the P2 scribed line, and the width of the P2 scribed line is 20 - 50 μm; and / or, the wavelength of the infrared laser is 1064 ± 106.4 nm, the wavelength of the green laser is 532 ± 53.2 nm, and the wavelength of the ultraviolet laser is 355 ± 35.5 nm.

[0016] In some specific embodiments, the distance between the P1 scribed line and the P2 scribed line is less than the width of the P2 scribed line, and the width of the P1 scribed line is less than or equal to the width of the P2 scribed line. In short, the manufacturing process takes the "P1 scribed line" as a parallel reference, avoiding complete coverage or even exceeding the range of the P1 scribed line. However, appropriate intersection theoretically does not affect the optoelectronic conversion performance of the device. Considering process stability, try to make the P2 scribed line parallel to the P1 scribed line and the distance approach 0. At the same time, the width of the P1 scribed line is less than or equal to the width of the P2 scribed line, mainly considering the deposition of the second electrode layer to form a groove with the required width.

[0017] According to yet another specific implementation and preferred aspect of the present invention, in step 5), the second electrode layer material is a transparent conductive oxide, and the second electrode layer deposition method includes any one or a combination of at least two of vacuum evaporation, magnetron sputtering, reactive plasma deposition, and chemical vapor deposition.

[0018] Preferably, the thickness of the second electrode layer is 10 - 1000 nm.

[0019] Preferably, the second electrode layer material includes any one or a combination of at least two of tin-doped indium oxide, indium tin oxide, indium zinc oxide, aluminum-doped zinc oxide, indium tungsten oxide, indium tin oxide doped with titanium, zinc oxide doped with boron, and indium oxide doped with cerium.

[0020] Alternatively, the second electrode layer material is a metal oxide, and the conductive metal in the metal oxide includes one or a combination of at least two of copper, silver, gold, iron, aluminum, tungsten, molybdenum, chromium, nickel, tantalum, vanadium, titanium, and manganese.

[0021] In short, the material of the second electrode layer can be a transparent conductive oxide (TCO), including but not limited to any one or a combination of at least two of FTO (tin-doped indium oxide), ITO (indium tin oxide), IZO (indium zinc oxide), AZO (aluminum-doped zinc oxide), IWO (tungsten-doped indium oxide), ITIO (indium tin titanium oxide), BZO (boron-doped zinc oxide), or ICO (cerium-doped indium oxide), or it can be a conductive metal, including but not limited to any one or a combination of at least two of high-conductivity metals and alloys such as copper, silver, gold, iron, aluminum, tungsten, molybdenum, chromium, nickel, tantalum, vanadium, titanium, and manganese. The deposition methods of the second electrode layer include but are not limited to any one or a combination of at least two of vacuum evaporation, magnetron sputtering, reactive plasma deposition, and chemical vapor deposition. The thickness of the second electrode layer is 10 - 1000 nm.

[0022] In addition, in step 6), a mechanical scribing P3 line is used, and the width of the P3 line is 20 - 200 μm. In short, a mechanical scribing P3 line is used. The depth of the P3 line is the thickness of the second electrode layer. P3 should ensure that the second electrode layer is completely cut off, that is, the second electrode layer is completely removed within the scribed area of P3. However, it should be ensured that the scribed edge does not warp to form a "crater", and at the same time, the damage to the device layer should be minimized as much as possible.

[0023] Another technical solution of the present invention is: a thin-film solar cell module interconnection structure, which includes a substrate, a first electrode layer, a device layer for photoelectric conversion, and a second electrode layer. A P1 line is formed on the first electrode layer, the device layer fills the P1 line, and a P2 line is formed near the P1 line in the device layer. The second electrode layer is deposited in the device layer, the first electrode layer, and the P2 line and forms a groove. A P3 line is formed on the second electrode layer near the P2 line and with the P2 line as a parallel reference. The scribing depth of the P3 line is the thickness of the second electrode layer, and the P3 line forms a groove. The groove is either connected to the groove or separated by the second electrode layer. The P1 line, the P2 line, and the interval between the P1 line and the P2 line form a dead zone, and the side of the P3 line forms the edge of the dead zone or the side of the P3 line is located within the dead zone.

[0024] Preferably, the device layer includes a P / N type functional layer, an intrinsic absorption layer, and an N / P type functional layer sequentially arranged from the substrate to the second electrode layer. The surface layer formed by the P / N type functional layer partially filling the P1 line is a planar layer, and both the intrinsic absorption layer and the N / P type functional layer are arranged in a planar layer layout.

[0025] In addition, the bottom thickness of the groove is less than the thickness of the P / N type functional layer.

[0026] Due to the implementation of the above technical solutions, the present invention has the following advantages compared with the prior art: In the existing scribing and sectional interconnection method of solar cell modules, for each sub-cell, there is a non-power generation area, also known as a dead zone, between the P1 scribing and the P3 scribing. Among them, in the device area between P2 and P3, after being blocked by P3, it is in a short-circuit state. Therefore, the existence of this dead zone directly reduces the effective power generation area, decreases the number of photo-generated carriers, resulting in a decrease in the short-circuit current (Isc). At the same time, lattice defects or impurities near the dead zone form recombination centers, accelerating the recombination of electron-hole pairs, and reducing the open-circuit voltage (Voc) and fill factor (FF). The P3 scribing used completely removes the absorption layer. That is, the P3 scribing should only isolate the back electrode layer. If the absorption layer is over-removed, it may cause the conductive channel between adjacent sub-cells to break, damage the series structure of the sub-cells, significantly increase the series resistance (Rs), reduce the fill factor (FF) and efficiency. At the same time, the dead zone range includes the entire area between P1 and P3 (generally, the width of the dead zone is 100 - 200 μm). Therefore, there are deficiencies such as low overall photoelectric conversion performance of the module. However, the present invention conducts an overall design on the preparation method of the interconnection structure of thin-film solar cell modules, skillfully solving the deficiencies and defects of the existing technology. After adopting the preparation method of the interconnection structure of thin-film solar cell modules, a substrate is selected, and a first electrode layer is deposited on the substrate. Then, P1 scribing is formed by scribing on the first electrode layer, and the scribing depth is the thickness of the first electrode layer. Then, P / N type functional layers, an intrinsic absorption layer, and N / P type functional layers are sequentially deposited on the first electrode layer and the substrate. The P / N type functional layer fills the scribed area, and the surface of the P / N type functional layer is flat. Then, with the P1 scribing as a parallel reference, a P2 scribing that is recessed from the P / N type functional layer to the first electrode layer is formed near the P1 scribing, and the scribing depth is the sum of the thicknesses of the N / P type functional layer, the intrinsic absorption layer, and the P / N type functional layer. Then, a second electrode layer is deposited. Part of the second electrode layer is formed on the N / P type functional layer, part is formed in the groove of the P2 scribing to cover the N / P type functional layer, the intrinsic absorption layer, the P / N type functional layer, and the corresponding groove walls, and the remaining part is formed on the first electrode layer and is located within the P2 scribing. A groove is formed in the second electrode layer located within the P2 scribing, and the width of the groove is smaller than the width of the P2 scribing. Finally, with the P2 scribing as a parallel reference, a P3 scribing is formed by scribing from the second electrode layer to the N / P type functional layer near the P2 scribing, and the depth of the P3 scribing is the thickness of the second electrode layer, where the sum of the width of the P1 scribing, the width of the P2 scribing, and the interval width between the P1 scribing and the P2 scribing is equal to the width of the dead zone;The P3 scribing forms a scribing groove, which is either connected to the recess or separated by the second electrode layer. Therefore, on the one hand, based on the premise of reducing the width of the dead zone, and by retaining the device functional layers formed by the P / N type functional layer, the intrinsic absorption layer, and the N / P type functional layer corresponding to the P3 scribing, not only can the photo-generated carriers of the device functional layer corresponding to the P3 scribing have a certain probability of being collected under the drift effect, thereby improving the overall photoelectric conversion performance of the module, but also the device functional layer can form absorption, avoiding the breakage of the conductive channels between adjacent sub-cells and reducing the series resistance. On the other hand, based on the recess formed by the second electrode layer, and the scribing groove is either connected to the recess or separated by the second electrode layer, not only can it avoid the edge of the scribing from warping and causing craters, but also it is necessary to control the damage of the device layer, eliminate the lattice defects near the dead zone, so as to improve the open circuit voltage (Voc) and the fill factor (FF).; Description of the Drawings

[0027] Figure 1 It is a schematic diagram of the interconnection structure of the thin-film solar cell module in the background technology; Figure 2 It is a schematic diagram of the interconnection structure of the thin-film solar cell module in Embodiment 1; Figure 3 It is a schematic diagram of the interconnection structure of the thin-film solar cell module in Embodiment 2.

[0028] Wherein: 0′, 1. Substrate; 1′, 2. First electrode layer; 3. Device layer; 2′, 30. P / N type functional layer; 3′, 31. Intrinsic absorption layer; 4′, 32. N / P type functional layer; 5′, 4. Second electrode layer; Ⅰ, Ⅰ′. Recess; Ⅱ, Ⅱ′. Scribing groove. Detailed Embodiments

[0029] In order to make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be described in detail below in conjunction with the drawings and specific embodiments. Many specific details are set forth in the following description in order to fully understand the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0030] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention.

[0031] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically and clearly defined.

[0032] In the present invention, unless otherwise clearly specified and limited, terms such as "mounted", "connected", "coupled", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] In the present invention, unless otherwise clearly specified and limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0034] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are only for illustrative purposes and do not represent the only embodiments.

[0035] Example 1: AsFigure 2 As shown in the figure, the interconnection structure of the thin-film solar cell module involved in this embodiment includes a substrate 1, a first electrode layer 2, a device layer 3 for photoelectric conversion, and a second electrode layer 4. A P1 scribeline is formed on the first electrode layer 2, the device layer 3 fills the P1 scribeline, and a P2 scribeline is formed near the P1 scribeline in the device layer 3. The second electrode layer 4 is deposited in the device layer 3, the first electrode layer 2, and the P2 scribeline to form a groove I. A P3 scribeline is formed on the second electrode layer 4 near the P2 scribeline and with the P2 scribeline as the parallel reference. The scribing depth of the P3 scribeline is the thickness of the second electrode layer 4, and the P3 scribeline forms a groove II. The P1 scribeline, the P2 scribeline, and the interval part between the P1 scribeline and the P2 scribeline constitute a dead zone. The side of the P3 scribeline constitutes the edge of the dead zone, and the groove II and the groove I are separated by the second electrode layer 4.

[0036] Specifically, the device layer 3 includes a P / N type functional layer 30, an intrinsic absorption layer 31, and an N / P type functional layer 32 sequentially arranged from the substrate to the second electrode layer 4. Part of the P / N type functional layer 30 fills the P1 scribeline to form a surface layer that is a flat layer, and both the intrinsic absorption layer 31 and the N / P type functional layer 32 are arranged in a flat layer layout. The bottom thickness of the groove is less than the thickness of the P / N type functional layer.

[0037] In this example, the thin-film solar cell module is a perovskite thin-film solar cell module with a size of 1200*600 mm, the number of sub-cells: 93, and the preparation method includes the following steps: 1) Select the substrate 1 and deposit and form the first electrode layer 2 on the substrate 1. The material of the substrate 1 is inorganic non-metal (such as flexible glass), the first electrode layer 2 is an FTO electrode layer, and it is formed on the flexible glass by a deposition method; 2) Use laser scribing to form a P1 scribeline on the first electrode layer 2, and the scribing depth is the thickness of the first electrode layer 2. At the same time, the width of the P1 scribeline is 40 μm; 3) Deposit the P / N type functional layer 30, the intrinsic absorption layer 31, and the N / P type functional layer 32 on the first electrode layer 2 and the substrate 1 in sequence. The P / N type functional layer 30 fills the scribed area, and the surface of the P / N type functional layer is flat; 4) Using the P1 scribeline as the parallel reference, laser scribe a P2 scribeline that is recessed from the P / N type functional layer to the first electrode layer 2 near the P1 scribeline. The scribing depth is the sum of the thicknesses of the N / P type functional layer 32, the intrinsic absorption layer 31, and the P / N type functional layer 30. At the same time, the distance between the P1 scribeline and the P2 scribeline is 20 μm, and the width of the P2 scribeline is 60 μm; 5) Deposit the second electrode layer 4, where the second electrode layer 4 is partially formed on the N / P type functional layer 32, partially formed in the grooves of the P2 scribed line on the corresponding groove walls of the N / P type functional layer 32, the intrinsic absorption layer 31, and the P / N type functional layer 30, and the remaining part is formed on the first electrode layer 2 and is located within the P2 scribed line. A groove Ⅰ is formed in the second electrode layer 4 within the P2 scribed line, and the width of the groove Ⅰ is 25 μm. At the same time, the second electrode layer 4 is a composite electrode layer; 6) With the P2 scribed line as the parallel reference, mechanically scribe near the P2 scribed line and scribe from the second electrode layer towards the N / P type functional layer to form the P3 scribed line. The depth of the P3 scribed line is the thickness of the second electrode layer 4. The sum of the width of the P1 scribed line, the width of the P2 scribed line, and the interval width between the P1 scribed line and the P2 scribed line is equal to the dead zone width (40 + 60 + 20 = 120 μm); the P3 scribed line forms a scribed groove Ⅱ, and the width of the scribed groove Ⅱ is 40 μm, and the scribed groove Ⅱ is separated from the groove Ⅰ by the second electrode layer 4.

[0038] Example 2: As Figure 3 shown, the interconnection structure of the thin-film solar cell module involved in this example is basically the same as that of Example 1, except for the P3 scribed line.

[0039] Specifically, the side of the P3 scribed line in this example is located within the dead zone.

[0040] In this example, the thin-film solar cell module is a perovskite thin-film solar cell module, with dimensions of 1200 * 600 mm, the number of sub-cells: 93, and the preparation method includes the following steps: 1) Select the substrate 1 and deposit and form the first electrode layer 2 on the substrate 1. The material of the substrate 1 is inorganic non-metal (such as flexible glass), the first electrode layer 2 is an FTO electrode layer, and it is formed on the flexible glass by the deposition method; 2) Use laser scribing on the first electrode layer 2 to form the P1 scribed line, and the scribing depth is the thickness of the first electrode layer 2. At the same time, the width of the P1 scribed line is 30 μm; 3) Deposit the P / N type functional layer 30, the intrinsic absorption layer 31, and the N / P type functional layer 32 in sequence on the first electrode layer 2 and the substrate 1. The P / N type functional layer 30 fills the scribed area, and the surface of the P / N type functional layer is flat; 4) With the P1 scribed line as the parallel reference, laser scribe near the P1 scribed line to form the P2 scribed line that is recessed from the P / N type functional layer towards the first electrode layer 2. The scribing depth is the sum of the thicknesses of the N / P type functional layer 32, the intrinsic absorption layer 31, and the P / N type functional layer 30. At the same time, the distance between the P1 scribed line and the P2 scribed line is 20 μm, and the width of the P2 scribed line is 40 μm; 5) Deposit the second electrode layer 4, where the second electrode layer 4 is partially formed on the N / P type functional layer 32, partially formed in the grooves of the N / P type functional layer 32, the intrinsic absorption layer 31, and the corresponding groove walls of the P / N type functional layer 30 in the P2 scribed line, and the remaining part is formed on the first electrode layer 2 and is located within the P2 scribed line. The second electrode layer 4 forms a groove Ⅰ with a width of 25 μm. At the same time, the second electrode layer 4 is a composite electrode layer; 6) With the P2 scribed line as the parallel reference, mechanically scribe near the P2 scribed line, and scribe from the second electrode layer towards the N / P type functional layer to form the P3 scribed line. The depth of the P3 scribed line is the thickness of the second electrode layer 4. The sum of the width of the P1 scribed line, the width of the P2 scribed line, and the interval width between the P1 scribed line and the P2 scribed line is equal to the dead zone width (30 + 40 + 20 = 90 μm); the P3 scribed line forms a scribed groove Ⅱ with a width of 40 μm, and the scribed groove Ⅱ communicates with the groove Ⅰ. At the same time, one side of the P3 scribed line is located within the dead zone.

[0041] Comparative Example 1: As Figure 1 shown, the interconnection structure of the thin-film solar cell module involved in this comparative example includes a substrate 0′, a first electrode layer 1′, a P / N type functional layer 2′, an intrinsic absorption layer 3′, an N / P type functional layer 4′, and a second electrode layer 5′. Among them, the first electrode layer 1′ is scribed into several small sections to form the P1 scribed line; then, at a distance as small as possible on one side of the "P1 scribed line", the device layer is scribed in parallel the same number of times to form the P2 scribed line; finally, after depositing the second electrode layer 5′, at a distance as small as possible on one side of the P2 scribed line, the device layer is scribed in parallel the same number of times to form the P3 scribed line. Therefore, the dead zone width is the maximum distance between the P1 scribed line and the P3 scribed line.

[0042] Taking the perovskite thin-film solar cell module as an example, its size is 1200*600 mm, the number of sub-cells: 93, and the preparation method includes the following steps: 1) Select the substrate 0′ and deposit and form the first electrode layer 1′ on the substrate 0′. The material of the substrate 0′ is inorganic non-metal (such as flexible glass), the first electrode layer 1′ is an FTO electrode layer, and it is formed on the flexible glass by the deposition method; 2) Scribe the P1 scribed line on the first electrode layer 1′, and the scribed thickness is equal to the thickness of the first electrode layer 1′, and the width of the formed laser scribing is 40 μm; 3) Deposit the P / N type functional layer 2′, the intrinsic absorption layer 3′, and the N / P type functional layer 4′ on the first electrode layer 1′ and the substrate 0′ in sequence. The P / N type functional layer 2′ fills the scribed area, and the surface of the P / N type functional layer 2′ is flat; 4) With the P1 scribing line as the parallel reference, a P2 scribing line is laser scribed near the P1 scribing line, which is recessed from the P / N type functional layer towards the first electrode layer 1'. The scribing depth is the sum of the thicknesses of the N / P type functional layer 4', the intrinsic absorption layer 3', and the P / N type functional layer 2'. At the same time, the distance between the P1 scribing line and the P2 scribing line is 20 μm, and the width of the P2 scribing line is 50 μm; 5) Deposit the second electrode layer 5'. Part of the second electrode layer 5' is formed on the N / P type functional layer 4', part is formed on the corresponding groove walls of the N / P type functional layer 4', the intrinsic absorption layer 3', and the P / N type functional layer 2' in the groove of the P2 scribing line, and the remaining part is formed on the first electrode layer 1' and is located within the P2 scribing line. The second electrode layer 5' forms a groove Ⅰ' with a width of 25 μm. At the same time, the second electrode layer 5' is a composite electrode layer; 6) With the P2 scribing line as the parallel reference, a P3 scribing line is laser scribed near the P2 scribing line, which is recessed from the second electrode layer 5' towards the P / N type functional layer 2'. The thickness of the P3 scribing line is the sum of the thicknesses of the second electrode layer 5', the N / P type functional layer 4', and the intrinsic absorption layer 3'. The width of the groove Ⅱ' formed by the P3 scribing line is 30 μm, and the distance between the P2 scribing line and the P3 scribing line is 50 μm. That is, the width of the dead zone is 40 μm + 20 μm + 50 μm + 50 μm + 30 μm = 190 μm.

[0043] In summary, for the interconnected structures of the solar cell modules in the examples and comparative examples, an IV tester is used to test the photovoltaic conversion efficiency of the cells and related electrical performance parameters under standard illumination power under a simulated solar light source. The specific test results are shown in Table 1.

[0044]

[0045] Based on the data analysis in Table 1, it can be seen that due to the different widths of the dead zones and the P3 scribing line being mechanically scribed and only scribing the second electrode layer, the open-circuit voltage, short-circuit current, fill factor, output power, and conversion efficiency of the entire solar cell module are all significantly improved.

[0046] In summary, the present application has the following technical advantages: 1) On the premise of reducing the width of the dead zone, by retaining the device functional layers formed by the P / N type functional layer, the intrinsic absorption layer, and the N / P type functional layer corresponding to the P3 scribing line, not only can the photo-generated carriers in the device functional layer corresponding to the P3 scribing line have a certain probability of being collected under the drift action, thereby improving the overall photovoltaic conversion performance of the module, but also the device functional layer can form absorption, avoiding the breakage of the conductive channels between adjacent sub-cells and reducing the series resistance; 2) Based on the grooves formed in the second electrode layer, and the scribing grooves are in communication with or separated by the second electrode layer from the grooves, which not only avoids the warping of the scribing edge and causing craters, but also must control the damage of the device layer, eliminate the lattice defects near the dead zone, so as to improve the open circuit voltage (Voc) and fill factor (FF); 3) Mechanical scribing is adopted for P3 scribing. Not only does mechanical scribing not generate thermal effects, there is also no risk of ablation to the device layer, and it has little impact on the performance of the overall series component.

[0047] The above has made a detailed description of the present invention, aiming to enable those skilled in this field of technology to understand the content of the present invention and implement it. However, it cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for preparing an interconnection structure of a thin-film solar cell module, characterized in that: It includes the following steps: 1) Selecting a substrate and depositing a first electrode layer on the substrate; 2) Scribing the first electrode layer to form a P1 scribe line, and the depth of the scribe line is equal to the thickness of the first electrode layer; 3) depositing a P / N type functional layer, an intrinsic absorption layer, and an N / P type functional layer on the first electrode layer and the substrate in sequence, wherein the P / N type functional layer fills the scribed area and the surface of the P / N type functional layer is a plane; 4) Taking the P1 scribe line as a parallel reference, a P2 scribe line is formed near the P1 scribe line, which is recessed from the P / N type functional layer to the first electrode layer, and the depth of the scribe line is the sum of the thicknesses of the N / P type functional layer, the intrinsic absorption layer, and the P / N type functional layer; 5) depositing a second electrode layer, wherein the second electrode layer is partially formed on the N / P type functional layer, partially formed on the groove wall corresponding to the N / P type functional layer, the intrinsic absorption layer, and the P / N type functional layer in the groove of the P2 scribe line, and the remaining portion is formed on the first electrode layer, and the second electrode layer located in the P2 scribe line forms a groove; 6) With the P2 line as a parallel reference, a P3 line is scribed from the second electrode layer to the N / P type functional layer near the P2 line, and the depth of the P3 line is the thickness of the second electrode layer, wherein the sum of the width of the P1 line, the width of the P2 line and the width of the interval between the P1 line and the P2 line is equal to the dead zone width; the P3 line forms a groove, and the groove and the groove are connected or separated by the second electrode layer.

2. The method for preparing the interconnection structure of thin-film solar cell modules according to claim 1, characterized in that: In step 1), the substrate material is an inorganic non-metal, a metal or a polymer.

3. The method for preparing the interconnection structure of thin-film solar cell modules according to claim 2, characterized in that: Inorganic non-metals include rigid glass and flexible glass; and / or, metals include stainless steel, aluminum alloys and titanium; and / or, polymers include Polyethylene terephthalate, polyethylene naphthalate, polyimide, parylene and polycarbonate.

4. The method for preparing the interconnection structure of thin-film solar cell modules according to claim 1, characterized in that: In step 1), the material of the first electrode layer is a transparent conductive oxide; and / or the deposition method of the first electrode layer includes any one of vacuum evaporation, magnetron sputtering, reactive plasma deposition, and chemical vapor deposition, or a combination of at least two thereof; and / or the thickness of the first electrode layer is 10-1000 nm.

5. The method for preparing the interconnection structure of thin-film solar cell modules according to claim 4, characterized in that: The first electrode layer material includes any one of fluorine-doped tin oxide, tin-doped indium oxide, zinc-doped indium oxide, aluminum-doped zinc oxide, indium oxide doped with tungsten, titanium-tin-doped indium oxide, boron-doped zinc oxide, and cerium-doped indium oxide, or a combination of at least two of them; and / or the first electrode layer material is a metal oxide, and the conductive metal in the metal oxide includes one of copper, silver, gold, iron, aluminum, tungsten, molybdenum, chromium, nickel, tantalum, vanadium, titanium, and manganese, or a combination of at least two of them.

6. The method for preparing the interconnection structure of thin-film solar cell modules according to claim 1, characterized in that: In step 2), nanosecond infrared or picosecond infrared or nanosecond ultraviolet or picosecond ultraviolet laser is used to scribe P1 lines, wherein the number of P1 lines is any integer greater than 1, and the number of P2 lines and P3 lines matches the number of P1 lines and is arranged one-to-one; and / or, the width of the P1 line is 20-50 μm; and / or, the infrared laser wavelength is 1064±106.4 nm, the green laser wavelength is 532±53.2 nm, and the ultraviolet laser wavelength is 355±35.5 nm.

7. The method for preparing the interconnection structure of thin-film solar cell modules according to claim 1, characterized in that: In step 3), the P / N type functional layer, the intrinsic absorption layer, and the N / P type functional layer constitute a device layer for photoelectric conversion, and the device layer is one or a combination of at least two of amorphous silicon, perovskite, copper indium gallium selenide, cadmium telluride, and gallium arsenide.

8. The method for preparing the interconnection structure of thin-film solar cell modules according to claim 1, characterized in that: In step 4), mechanical scribing or nanosecond infrared or picosecond infrared or nanosecond green light or picosecond green light or nanosecond ultraviolet or picosecond ultraviolet laser scribing is used to scribing P2 lines, and the width of the P2 lines is 20-50 μm.

9. The method for preparing the interconnection structure of thin-film solar cell modules according to claim 8, characterized in that: The infrared laser wavelength is 1064±106.4nm, the green laser wavelength is 532±53.2nm, and the ultraviolet laser wavelength is 355±35.5nm.

10. The method for preparing the interconnection structure of thin-film solar cell modules according to claim 8, characterized in that: The distance between the P1 scribe line and the P2 scribe line is smaller than the width of the P2 scribe line, and the width of the P1 scribe line is smaller than or equal to the width of the P2 scribe line.

11. The method for preparing the interconnection structure of thin-film solar cell modules according to claim 1, characterized in that: In step 5), the second electrode layer material is a transparent conductive oxide; and / or the second electrode layer deposition method includes any one of vacuum evaporation, magnetron sputtering, reactive plasma deposition, and chemical vapor deposition, or a combination of at least two thereof; and / or the thickness of the second electrode layer is 10-1000 nm.

12. The method for preparing the interconnection structure of thin-film solar cell modules according to claim 11, characterized in that: The second electrode layer material includes any one of fluorine-doped tin oxide, tin-doped indium oxide, zinc-doped indium oxide, aluminum-doped zinc oxide, indium oxide doped with tungsten, titanium-tin-doped indium oxide, boron-doped zinc oxide, and cerium-doped indium oxide, or a combination of at least two of them; and / or, the second electrode layer material is a metal oxide, and the conductive metal in the metal oxide includes one of copper, silver, gold, iron, aluminum, tungsten, molybdenum, chromium, nickel, tantalum, vanadium, titanium, and manganese, or a combination of at least two of them.

13. The method for preparing the interconnection structure of thin-film solar cell modules according to claim 1, characterized in that: In step 6), mechanical scribing is used to scribe P3 lines, and the width of P3 lines is 20-200 μm.

14. A thin-film solar cell module interconnection structure, comprising a substrate, a first electrode layer, a device layer for photoelectric conversion, and a second electrode layer, wherein a P1 scribe line is formed on the first electrode layer, the device layer fills the P1 scribe line, and the device layer forms a P2 scribe line near the P1 scribe line, and the second electrode layer is deposited in the device layer, the first electrode layer, and the P2 scribe line to form a groove, It is characterized in that A P3 line is formed on the second electrode layer, which is close to the P2 line and parallel to the P2 line, wherein the engraving depth of the P3 line is the thickness of the second electrode layer, and the P3 line forms a groove, and the groove and the groove are connected or separated by the second electrode layer, the P1 line, the P2 line and the interval between the P1 line and the P2 line constitute a dead zone, and the side of the P3 line constitutes the edge of the dead zone or the side of the P3 line is located in the dead zone.

15. The thin-film solar cell module interconnection structure according to claim 14, characterized in that: The device layer includes a P / N type functional layer, an intrinsic absorption layer and an N / P type functional layer arranged in sequence from the substrate to the second electrode layer, wherein the surface layer formed by filling the P1 line in the P / N type functional layer is a planar layer, and the intrinsic absorption layer and the N / P type functional layer are both in a planar layer layout.

16. The thin-film solar cell module interconnection structure according to claim 15, characterized in that: The groove bottom thickness of the groove is smaller than the thickness of the P / N type functional layer.

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