A curved cadmium telluride thin film photovoltaic module and a method of manufacturing the same

Abstract

This invention relates to the field of semiconductor technology and discloses a curved cadmium telluride thin-film photovoltaic module and its fabrication method. The fabrication method includes: depositing a transparent conductive layer and a cell layer sequentially from bottom to top on one side surface of a glass substrate; forming a P1 laser groove penetrating the transparent conductive layer and the cell layer; sequentially forming a P2 laser groove penetrating the cell layer and a contact layer, the contact layer being located on the surface of the cell layer and covering the inner wall of the P2 laser groove; forming a P3 laser groove penetrating the contact layer and the cell layer, wherein the interior or bottom of the P3 laser groove is a filling layer; performing a hot bending process; forming a first back electrode layer on the surface of the filling layer and a second back electrode layer on the surface of the contact layer; the porosity of the first back electrode layer is greater than that of the second back electrode layer; and removing the filling layer and the first back electrode layer corresponding to the P3 laser groove position using a film removal solution to form a groove. This invention can meet the integration and fabrication of cadmium telluride thin-film modules with arbitrary curved shapes, improving the design flexibility and efficiency of the modules.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, specifically to a curved cadmium telluride thin-film photovoltaic module and its preparation method. Background Technology

[0002] Currently, thin-film photovoltaic modules employ an inline structure, which is primarily formed using laser etching or mechanical scribing processes. These processes offer advantages such as high control precision and suitability for large-scale industrialization. However, laser etching or mechanical scribing is mainly suitable for planar substrates with regular shapes, and cannot process irregularly shaped curved substrates. This limits the development and application of curved thin-film photovoltaic modules. In some technologies, cadmium telluride modules utilize a hot bending process, first pre-preparing a portion of the high-temperature resistant film layer, then hot bending, followed by curved surface coating and integration. However, existing laser equipment cannot etch irregular curved surfaces. Current curved laser or mechanical scribing equipment can only process hyperboloid products with simple shapes and small deformations, and cannot process hyperboloid products with complex shapes and large deformations. Furthermore, if a metal electrode layer is formed before hot bending, the hot bending process may damage the metal electrode layer.

[0003] Therefore, a method for fabricating curved cadmium telluride thin-film photovoltaic modules is needed to avoid laser etching of the curved photovoltaic modules after hot bending, while avoiding damage to the metal back electrode and obstruction and influence on the hot bending and Cl processing processes, thereby improving the design flexibility of the curved substrate. Summary of the Invention

[0004] In view of this, the present invention provides a curved cadmium telluride thin-film photovoltaic module and its preparation method, so as to solve the problems in the related technology that the laser etching process is not suitable for curved substrates with irregular shape and large deformation, and that the hot bending process may damage the metal electrode layer.

[0005] In a first aspect, the present invention provides a method for preparing a curved cadmium telluride thin-film photovoltaic module, the method comprising:

[0006] A glass substrate is provided, and a transparent conductive layer and a battery layer are deposited sequentially from bottom to top on one side surface of the glass substrate;

[0007] A P1 laser groove is formed, which penetrates the transparent conductive layer and the battery layer. The filling material of the P1 laser groove is an insulating material.

[0008] A P2 laser groove and a contact layer are formed sequentially; the P2 laser groove penetrates the battery layer; the contact layer is located on the surface of the battery layer and covers the inner wall of the P2 laser groove.

[0009] A P3 laser groove is formed, which penetrates the contact layer and the battery layer. The interior or bottom of the P3 laser groove is a filling layer. The contact layer exposes the surface of the filling layer inside or at the bottom of the P3 laser groove, thus obtaining the intermediate component structure.

[0010] The intermediate component structure undergoes hot bending and Cl treatment processes.

[0011] A back electrode layer is formed, comprising a first back electrode layer and a second back electrode layer; wherein, the second back electrode layer is located on the surface of the contact layer opposite to the battery layer and fills the P2 laser groove; the first back electrode layer is located inside or on the surface of the filling layer at the bottom of the P3 laser groove; the porosity of the first back electrode layer is greater than that of the second back electrode layer; and the thickness of the first back electrode layer is less than that of the second back electrode layer.

[0012] The filler layer and the first back electrode layer corresponding to the P3 laser groove position are removed by using a membrane removal solution through the first back electrode layer to form a groove. The groove penetrates the second back electrode layer, the contact layer and the battery layer.

[0013] The method for fabricating curved cadmium telluride thin-film photovoltaic modules provided by this invention first forms a P3 laser groove with a filling layer inside or at the bottom, and makes the contact layer cover the part outside the P3 laser groove, exposing the surface of the filling layer. Next, the module is hot-bent. Finally, taking advantage of the deposition characteristics of the back electrode layer, a first back electrode layer with a large porosity is formed on the surface of the filling layer, and a second back electrode layer with a small porosity is formed on the surface of the contact layer. Finally, a film removal solution is used to remove the filling layer inside or at the bottom of the P3 laser groove through the first back electrode layer to form a groove. The groove can separate and insulate the second back electrode layers on both sides, realizing the separation and insulation between adjacent module units. First, completing all laser etching integration processes before the hot bending process avoids etching the curved photovoltaic modules, thus eliminating the need for and limitations on curved laser equipment and processes. This allows for the integration and fabrication of cadmium telluride thin-film modules with arbitrary curved shapes, reducing the radius of curvature to below 1m. Second, forming the back electrode layer after the hot bending process avoids obstruction and interference from the back electrode layer, improving the effectiveness of these processes. This enhances the module's design flexibility, stability, reliability, and efficiency, while also preventing damage to the back electrode layer during hot bending, thus improving its reliability. Third, utilizing the deposition characteristics of the back electrode layer, a first and second back electrode layer with different porosities are simultaneously formed, eliminating the need for additional process steps, simplifying the process flow, and improving efficiency. Furthermore, using a film removal solution to remove the filler layer through the first back electrode layer simultaneously removes the film layer above the filler layer, forming a groove. The process is simple and effective. Therefore, the method for preparing curved cadmium telluride thin-film photovoltaic modules provided by the present invention can improve the effect of hot bending process, reduce the minimum achievable curvature radius of photovoltaic modules, improve the design flexibility, stability, reliability and module efficiency of curved cadmium telluride thin-film modules, and at the same time simplify the process flow and improve process efficiency.

[0014] In one optional embodiment, the step of sequentially forming the P2 laser groove and the contact layer includes:

[0015] The P2 laser groove is formed by etching the battery layer with a second laser.

[0016] A contact layer is formed on the side of the battery layer facing away from the transparent conductive layer, and the contact layer also covers the inner wall of the P2 laser groove.

[0017] In one alternative implementation, the filler layer is a sacrificial layer;

[0018] The steps for forming the P3 laser groove include:

[0019] The P3 laser groove is formed by etching the contact layer and the battery layer with a third laser.

[0020] A filling layer is formed inside the P3 laser groove; the contact layer exposes the surface of the filling layer inside the P3 laser groove.

[0021] In one alternative implementation, the first back electrode layer is located on the surface of the filling layer inside the P3 laser slot;

[0022] The steps for forming the groove include:

[0023] The filler layer inside the P3 laser groove is removed by using a stripping solution through the first back electrode layer, and the first back electrode layer located on the surface of the filler layer inside the P3 laser groove is also removed, forming a groove that penetrates the second back electrode layer, the contact layer, and the battery layer.

[0024] In one optional embodiment, the filling layer is made of an oxide material, a photoresist material, a ceramic material, a metal material, or a group II-VI compound material;

[0025] Oxide materials include ZnO, MgZnO, or MgO;

[0026] Ceramic materials include SiO2, Si3N4, or Al2O3;

[0027] Metallic materials include Cr or Al;

[0028] Group II-VI compound materials include CdS, CdS:O, CdSe, CdSe:O, and MgTe.

[0029] In one alternative implementation, the filling layer is a buffer layer;

[0030] The step of sequentially depositing a transparent conductive layer and a battery layer on a glass substrate includes:

[0031] A transparent conductive layer, a filler layer, and a battery layer are sequentially deposited on a glass substrate;

[0032] The steps for forming the P2 laser groove include:

[0033] A second laser etching process is used to form a P2 laser groove between the filler layer and the battery layer; the P2 laser groove penetrates through the filler layer and the battery layer.

[0034] The steps for forming the P3 laser groove include:

[0035] A third laser etching method is used to etch the contact layer and the battery layer to form a P3 laser groove; the P3 laser groove penetrates the battery layer and exposes the filling layer; the bottom of the P3 laser groove is the filling layer.

[0036] In one alternative implementation, the first back electrode layer is located on the surface of the filling layer at the bottom of the P3 laser slot;

[0037] The steps for forming the groove include:

[0038] The filler layer corresponding to the bottom of the P3 laser groove is removed by using a membrane removal solution through the first back electrode layer, and the first back electrode layer on the surface of the filler layer at the bottom of the P3 laser groove is removed to form a groove, while the filler layer on both sides of the groove is retained.

[0039] In one alternative embodiment, the filling layer is made of ZnO, MgZnO, ZnSO, ZnS, or CdZnS.

[0040] In one alternative embodiment, the thickness ratio of the first back electrode layer and the second back electrode layer is less than 1:10.

[0041] The thickness of the second back electrode layer is 50nm to 200nm, and the porosity of the first back electrode layer is <10%.

[0042] The first back electrode layer is a porous or discontinuous layer, and the porosity of the first back electrode layer is >30%.

[0043] The material of the back electrode layer is Mo, Ni, Ti, and the corresponding nitrides or nitrogen oxides;

[0044] The first and second back electrode layers are suitable for preparation by electroplating, electroless plating, sputtering or evaporation processes;

[0045] The thickness of the filling layer is 20 nm to 10 μm;

[0046] The filler layer is suitable for preparation by sputtering, evaporation, roll coating or printing processes;

[0047] The contact layer material is Pd, Ag, Cu, Ni, Ti, selenium oxide, ZnTe, or CdZnTe;

[0048] The thickness of the contact layer is 1nm to 20nm;

[0049] The contact layer is suitable for preparation by electroplating, electroless plating, sputtering or evaporation processes;

[0050] The insulating material is SiO2, Si3N4 or Al2O3;

[0051] The battery layer is made of CdTe, CdSTe, CdSeTe, CdMgTe, CdZnTe, CdSSeTe, or CdZnSSeTe.

[0052] The method for preparing curved cadmium telluride thin-film photovoltaic modules provided by this invention has a thickness ratio of less than or equal to 1:10 for the first back electrode layer and the second back electrode layer, a porosity of less than 10% for the second back electrode layer, and a porosity of greater than 30% for the first back electrode layer. This allows the film removal solution to enter the filler layer through the gaps or pores of the second back electrode layer, thereby improving the corrosion removal rate of the filler layer, increasing process efficiency, reducing damage to the first back electrode layer, and improving the reliability and yield of the module.

[0053] In one alternative embodiment, the stripping solution contains a material that can corrode the filler layer;

[0054] The membrane removal solution can be an acidic solution, an alkaline solution, or an organic solvent;

[0055] Acidic solutions include phosphoric acid, sulfuric acid, acetic acid, or hydrofluoric acid;

[0056] Alkaline solutions include sodium hydroxide, potassium hydroxide, ferric chloride, or hydrogen peroxide;

[0057] Organic solvents include ethanol, acetone, methyl pyrrolidone, or ethanolamine;

[0058] The concentration of the membrane removal solution is 1% to 100%, and the temperature is 20℃ to 100℃.

[0059] In a second aspect, the present invention provides a curved cadmium telluride thin-film photovoltaic module, the curved cadmium telluride thin-film photovoltaic module comprising:

[0060] A glass substrate, a transparent conductive layer, a battery layer, a contact layer, and a second back electrode layer are stacked in sequence.

[0061] The P1 laser groove penetrates the transparent conductive layer and the battery layer. The filling material of the P1 laser groove is an insulating material.

[0062] P2 laser groove, penetrating the battery layer;

[0063] The groove penetrates the second back electrode layer, the contact layer, and the battery layer, and exposes the surface of the transparent conductive layer;

[0064] The contact layer and back electrode layer also fill the P2 laser groove and cover the surface of the P1 laser groove.

[0065] The curved cadmium telluride thin-film photovoltaic module provided by the present invention can achieve separation and insulation of the contact layer and the second back electrode layer on both sides of the groove by setting the groove; at the same time, the curved cadmium telluride thin-film photovoltaic module can be of any curved shape, which improves the design flexibility, stability, reliability and module efficiency of the curved cadmium telluride thin-film module.

[0066] In one optional embodiment, a buffer layer is further provided between the transparent conductive layer and the battery layer;

[0067] The P1 laser groove penetrates the transparent conductive layer, buffer layer, and battery layer;

[0068] The P2 laser slot penetrates both the buffer layer and the battery layer;

[0069] The groove runs through the buffer layer, battery layer, contact layer, and battery layer. Attached Figure Description

[0070] To more clearly illustrate the technical solutions in the specific embodiments or related technologies of the present invention, the drawings used in the description of the specific embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0071] Figure 1 This is a schematic flowchart of a method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0072] Figure 2 This is a schematic diagram illustrating the specific process of a method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0073] Figure 3 This is a schematic diagram of the structure for forming the P1 laser groove in a method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0074] Figure 4 This is a schematic diagram of the structure for filling the P1 laser groove in a method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0075] Figure 5 This is a schematic diagram of the structure forming the P2 laser groove in a method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0076] Figure 6 This is a schematic diagram of the structure for forming a contact layer in a method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0077] Figure 7 This is a schematic diagram of the structure forming the P3 laser groove in a method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0078] Figure 8 This is a schematic diagram of the structure of the filling layer in a method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0079] Figure 9 This is a schematic diagram of the structure of the back electrode layer formed in a method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0080] Figure 10 This is a schematic diagram of the structure forming the groove in a method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0081] Figure 11 This is a schematic diagram illustrating the specific process of another method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0082] Figure 12 This is a schematic diagram of the structure for forming the P1 laser groove in another method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0083] Figure 13 This is a schematic diagram of the structure for filling the P1 laser groove in another method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0084] Figure 14 This is a schematic diagram of the structure for forming the P2 laser groove in another method for fabricating a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0085] Figure 15 This is a schematic diagram of the structure for forming a contact layer in another method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0086] Figure 16 This is a schematic diagram of the structure forming the P3 laser groove in another method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0087] Figure 17 This is a schematic diagram of the structure for forming the back electrode layer in another method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0088] Figure 18 This is a schematic diagram of the structure forming the groove in a method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0089] Figure label:

[0090] 10. Glass substrate; 20. Transparent conductive layer; 30. Battery layer; 40. Contact layer; 51. First back electrode layer; 52. Second back electrode layer; 60. Filling layer; 61. Sacrificial layer; 62. Buffer layer; 81. P1 laser groove; 82. P2 laser groove; 83. P3 laser groove; 90. Groove. Detailed Implementation

[0091] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the invention, not the entire structure.

[0092] In the following description, descriptions of well-known structures and techniques are omitted to avoid unnecessarily obscuring the concepts of the present invention. Various structural schematic diagrams according to embodiments of the present invention are shown in the accompanying drawings. These drawings are not to scale, and some details are enlarged for clarity, and some details may be omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate in practice due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed. In the context of the present invention, when a layer / element is referred to as being "on" another layer / element, the layer / element may be directly on the other layer / element, or there may be an intermediate layer / element between them. Additionally, if a layer / element is "on" another layer / element in one orientation, then when the orientation is reversed, the layer / element may be "below" the other layer / element.

[0093] Currently, thin-film photovoltaic modules employ an inline structure, which is primarily formed using laser etching or mechanical scribing processes. These processes offer advantages such as high control precision and suitability for large-scale industrialization. However, laser etching or mechanical scribing is mainly suitable for planar substrates with regular shapes, and cannot process irregularly shaped curved substrates. This limits the development and application of curved thin-film photovoltaic modules. In some technologies, cadmium telluride modules utilize a hot bending process, first pre-preparing a portion of the high-temperature resistant film layer, then hot bending, followed by curved surface coating and integration. However, existing laser equipment cannot etch irregular curved surfaces. Current curved laser or mechanical scribing equipment can only process hyperboloid products with simple shapes and small deformations, and cannot process hyperboloid products with complex shapes and large deformations. Furthermore, if a metal electrode layer is formed before hot bending, the hot bending process may damage the metal electrode layer.

[0094] Therefore, a method for fabricating curved cadmium telluride thin-film photovoltaic modules is needed to avoid laser etching of the curved photovoltaic modules after hot bending, while avoiding damage to the metal back electrode and obstruction and influence on the hot bending and Cl processing processes, thereby improving the design flexibility of the curved substrate.

[0095] like Figure 1 As shown, this embodiment provides a method for preparing a curved cadmium telluride thin-film photovoltaic module, which includes, but is not limited to, steps S101 to S107.

[0096] Step S101: Provide a glass substrate 10, and deposit a transparent conductive layer 20 and a battery layer 30 sequentially from bottom to top on one side surface of the glass substrate 10.

[0097] Step S102: Forming P1 laser groove 81, which penetrates the transparent conductive layer 20 and the battery layer 30. The filling material of P1 laser groove 81 is an insulating material.

[0098] In step S103, a P2 laser groove 82 and a contact layer 40 are formed sequentially; the P2 laser groove 82 penetrates the battery layer 30; the contact layer 40 is located on the surface of the battery layer 30 and covers the inner wall of the P2 laser groove 82.

[0099] Step S104: A P3 laser groove 83 is formed, which penetrates the contact layer 40 and the battery layer 30. The interior or bottom of the P3 laser groove 83 is a filling layer 60. The contact layer 40 exposes the surface of the filling layer 60 inside or at the bottom of the P3 laser groove 83, thus obtaining an intermediate component structure.

[0100] Step S105: Perform hot bending and Cl treatment processes on the intermediate component structure;

[0101] Step S106: Form a back electrode layer, which includes a first back electrode layer 51 and a second back electrode layer 52; wherein, the second back electrode layer 52 is located on the surface of the contact layer 40 facing away from the battery layer 30 and fills the P2 laser groove 82; the first back electrode layer 51 is located inside the P3 laser groove 83 or on the surface of the filling layer 60 at the bottom; the porosity of the first back electrode layer 51 is greater than the porosity of the second back electrode layer 52; the thickness of the first back electrode layer 51 is less than the thickness of the second back electrode layer 52.

[0102] In step S107, the filler layer 60 and the first back electrode layer 51 corresponding to the P3 laser groove 83 position are removed by using a film removal solution through the first back electrode layer 51 to form a groove 90. The groove 90 penetrates the second back electrode layer 52, the contact layer 40 and the battery layer 30.

[0103] In some alternative implementations, the resulting curved cadmium telluride thin-film photovoltaic module has a radius of curvature of <1m and an irregular shape.

[0104] In practice, when forming the back electrode layer, the back electrode layer forms quickly on the contact layer surface, and the formed second back electrode layer 52 has good density and uniformity; while the back electrode layer forms slowly directly on the filler layer surface, and the formed first back electrode layer 51 is thin, has high porosity and is discontinuous, making it easy for the membrane removal solution to pass through.

[0105] In the intermediate component structure, the contact layer 40 covers the surface of the battery layer 30 and the inner wall of the P2 laser groove 82, and exposes the surface of the filling layer 60 inside or at the bottom of the P3 laser groove 83, so that the intermediate component structure has no contact layer 40 on the surface of the filling layer 60. After the hot bending process, a first back electrode layer 51 with high porosity and thinner structure is formed on the surface of the filling layer 60 inside or at the bottom of the P3 laser groove 83, while a second back electrode layer 52 with low porosity and thicker structure is formed on the surface of the contact layer 40 and inside the P2 laser groove 82. Finally, the film removal solution can pass through the first back electrode layer 51 to etch the filling layer 60, removing the filling layer 60 and the first back electrode layer 51 above it, thus obtaining a metal-free groove 90, achieving the separation and electrical insulation effect of the second back electrode layer 52. Therefore, the method for fabricating curved cadmium telluride thin-film photovoltaic modules provided in this embodiment completes the laser etching process of P1 laser groove 81, P2 laser groove 82 and P3 laser groove 83 before the hot bending process. The P3 laser groove 83 has a filling layer 60 inside or at the bottom. After the hot bending process, the first back electrode layer 51 and the second back electrode layer 52 are formed. The second back electrode layer 52 is separated by forming a groove 90 with a film removal solution, thereby achieving separation and insulation between adjacent module units. This overcomes the problem that the traditional P3 laser etching process is only suitable for planar substrates or substrates with regular shapes and small deformation, and cannot meet the processing requirements of substrates with large deformation and irregular shapes. It can realize the fabrication of P3 insulating laser grooves on arbitrarily formed substrates and reduce the radius of curvature to below 1m.

[0106] The method for fabricating curved cadmium telluride thin-film photovoltaic modules provided in this embodiment first forms a P3 laser groove with a filling layer inside or at the bottom, and makes the contact layer cover the part outside the P3 laser groove, exposing the surface of the filling layer. Next, the module is hot-bent. Finally, taking advantage of the deposition characteristics of the back electrode layer, a first back electrode layer with a large porosity is formed on the surface of the filling layer, and a second back electrode layer with a small porosity is formed on the surface of the contact layer. Finally, a film removal solution is used to remove the filling layer inside or at the bottom of the P3 laser groove through the first back electrode layer to form a groove. The groove can separate and insulate the second back electrode layers on both sides, realizing the separation and insulation between adjacent module units. First, completing all laser etching integration processes before the hot bending process avoids etching the curved photovoltaic modules, thus eliminating the need for and limitations on curved laser equipment and processes. This allows for the integration and fabrication of cadmium telluride thin-film modules with arbitrary curved shapes, reducing the radius of curvature to below 1m. Second, forming the back electrode layer after the hot bending process avoids obstruction and interference from the back electrode layer, improving the effectiveness of these processes. This enhances the module's design flexibility, stability, reliability, and efficiency, while also preventing damage to the back electrode layer during hot bending, thus improving its reliability. Third, utilizing the deposition characteristics of the back electrode layer, a first and second back electrode layer with different porosities are simultaneously formed, eliminating the need for additional process steps, simplifying the process flow, and improving efficiency. Furthermore, using a film removal solution to remove the filler layer through the first back electrode layer simultaneously removes the film layer above the filler layer, forming a groove. The process is simple and effective. Therefore, the method for preparing curved cadmium telluride thin-film photovoltaic modules provided in this embodiment can improve the effect of hot bending process, reduce the minimum curvature radius that photovoltaic modules can achieve, improve the design flexibility, stability, reliability and module efficiency of curved cadmium telluride thin-film modules, and at the same time simplify the process flow and improve process efficiency.

[0107] In some alternative implementations, the step of forming the P1 laser groove 81 includes:

[0108] A P1 laser groove 81 is formed by laser etching of the transparent conductive layer 20 and the battery layer 30; the P1 laser groove 81 penetrates the transparent conductive layer 20 and the battery layer 30.

[0109] The P1 laser groove 81 is filled with the first filling material.

[0110] In some optional embodiments, the step of sequentially forming the P2 laser groove 82 and the contact layer 40 includes:

[0111] A second laser etching process is used to form a P2 laser groove 82 in the cell layer 30.

[0112] A contact layer 40 is formed on the side of the battery layer 30 facing away from the transparent conductive layer 20, and the contact layer 40 also covers the inner wall of the P2 laser groove 82.

[0113] In some alternative implementations, the filler layer 60 is a sacrificial layer 61;

[0114] The steps for forming the P3 laser groove 83 include:

[0115] A third laser etching process is used to etch the contact layer 40 and the battery layer 30 to form a P3 laser groove 83.

[0116] A filling layer 60 is formed inside the P3 laser groove 83; the contact layer 40 exposes the surface of the filling layer 60 inside the P3 laser groove 83.

[0117] In some alternative embodiments, the first back electrode layer 51 is located on the surface of the filling layer 60 inside the P3 laser slot 83;

[0118] The step of forming the groove 90 includes:

[0119] The filler layer 60 inside the P3 laser groove 83 is removed by using a membrane removal solution through the first back electrode layer 51, and the first back electrode layer 51 located on the surface of the filler layer 60 inside the P3 laser groove 83 is removed to form a groove 90. The groove 90 penetrates the second back electrode layer 52, the contact layer 40 and the battery layer 30.

[0120] In some alternative embodiments, the filling layer 60 is made of an oxide material, a photoresist material, a ceramic material, or a metal material;

[0121] Oxide materials include ZnO, MgZnO, or MgO;

[0122] Ceramic materials include SiO2, Si3N4, or Al2O3;

[0123] Metallic materials include Cr or Al.

[0124] In some alternative implementations, the filler layer 60 is a buffer layer 62;

[0125] The step of sequentially depositing a transparent conductive layer 20 and a battery layer 30 on a glass substrate 10 includes:

[0126] A transparent conductive layer 20, a filler layer 60, and a battery layer 30 are sequentially deposited on a glass substrate 10.

[0127] The steps for forming the P2 laser groove 82 include:

[0128] A second laser etching filler layer 60 and a battery layer 30 are used to form a P2 laser groove 82; the P2 laser groove 82 penetrates the filler layer 60 and the battery layer 30.

[0129] The steps for forming the P3 laser groove 83 include:

[0130] A third laser etching process is used to etch the contact layer 40 and the battery layer 30 to form a P3 laser groove 83. The P3 laser groove 83 penetrates the contact layer 40 and the battery layer 30 and exposes the filling layer 60. The bottom of the P3 laser groove 83 is the filling layer 60.

[0131] In some alternative embodiments, the first back electrode layer 51 is located on the surface of the filling layer 60 at the bottom of the P3 laser groove 83;

[0132] The step of forming the groove 90 includes:

[0133] The filler layer 60 corresponding to the bottom of the P3 laser groove 83 is removed by using a membrane removal solution through the first back electrode layer 51, and the first back electrode layer 51 on the surface of the filler layer 60 at the bottom of the P3 laser groove 83 is removed to form a groove 90, while the filler layer 60 on both sides of the groove 90 is retained.

[0134] In some alternative embodiments, the material of the filler layer 60 is ZnO, MgZnO, ZnSO, ZnS, or CdZnS.

[0135] In practice, the padding layer 60 is a buffer layer, and part of the buffer layer will eventually be retained in the component as part of the component.

[0136] In some optional embodiments, the thickness ratio of the first back electrode layer 51 and the second back electrode layer 52 is less than or equal to 1:10, for example, the thickness ratio of the first back electrode layer 51 and the second back electrode layer 52 is 1:10, 1:20, or 1:100.

[0137] The thickness of the second back electrode layer 52 is 50nm to 200nm, for example, 50nm, 100nm, 120nm, 150nm or 200nm, etc.

[0138] The porosity of the second back electrode layer 52 is <10%;

[0139] The thickness of the second back electrode layer 52 is 1nm to 20nm, such as 1nm, 3nm, 5nm, 10nm, 15nm or 20nm.

[0140] The first back electrode layer 51 is a porous or discontinuous layer, and the porosity of the first back electrode layer 51 is >30%.

[0141] The method for fabricating curved cadmium telluride thin-film photovoltaic modules provided in this embodiment has a thickness ratio of less than or equal to 1:10 for the first back electrode layer and the second back electrode layer, a porosity of less than 10% for the second back electrode layer, and a porosity of greater than 30% for the first back electrode layer. This allows the film removal solution to enter the filler layer through the gaps or pores of the second back electrode layer, thereby improving the corrosion removal rate of the filler layer, increasing process efficiency, reducing damage to the first back electrode layer, and improving the reliability and yield of the module.

[0142] In some alternative embodiments, the porosity of the second back electrode layer 52 is <5%; in some examples, the porosity of the second back electrode layer 52 is <3%. The porosity of the second back electrode layer 52 is <10%; the first back electrode layer 51 is a porous or discontinuous layer with a porosity >30%.

[0143] In some alternative implementations, the porosity of the first back electrode layer 51 is >50%; in some examples, the porosity of the first back electrode layer 51 is >60%.

[0144] In some alternative implementations, the material of the back electrode layer is Mo, Ni, Ti, and the corresponding nitrides or oxynitrides.

[0145] The first back electrode layer 51 and the second back electrode layer 52 are suitable for preparation by electroplating, electroless plating, sputtering or evaporation processes.

[0146] In some alternative embodiments, the thickness of the filler layer 60 is 20 nm to 10 μm;

[0147] The filler layer 60 is suitable for preparation by sputtering, evaporation, roll coating or printing processes;

[0148] The material of the contact layer 40 is Pd, Ag, Cu, Ni, Ti, selenium oxide, ZnTe, or CdZnTe;

[0149] The thickness of the contact layer 40 is 1 nm to 20 nm;

[0150] The contact layer 40 is suitable for preparation by electroplating, electroless plating, sputtering or evaporation processes;

[0151] The insulating material is SiO2, Si3N4 or Al2O3;

[0152] The material of the battery layer 30 is CdTe, CdSTe, CdSeTe, CdMgTe, CdZnTe, CdSSeTe, or CdZnSSeTe.

[0153] In some alternative embodiments, the stripping solution contains a material that can corrode the filler layer 60;

[0154] The membrane removal solution can be an acidic solution, an alkaline solution, or an organic solvent;

[0155] Acidic solutions include phosphoric acid, sulfuric acid, acetic acid, or hydrofluoric acid;

[0156] Alkaline solutions include sodium hydroxide, potassium hydroxide, ferric chloride, or hydrogen peroxide;

[0157] Organic solvents include ethanol, acetone, methyl pyrrolidone, or ethanolamine;

[0158] The concentration of the membrane removal solution is 1% to 100%, and the temperature is 20℃ to 100℃.

[0159] In practice, the choice of the stripping solution depends on the material of the filler layer 60. In some examples, the material of the filler layer 60 is ZnO, and the stripping solution is a 10% phosphoric acid solution; the material of the filler layer 60 is CdSe, and the stripping solution is a 10% hydrochloric acid solution; in some examples, the material of the filler layer 60 is photoresist or nano-silicon, and the stripping solution is a 10% NaOH solution.

[0160] In some alternative embodiments, the membrane removal solution permeates through the microporous structure of the first back electrode layer 51 to the location of the filling layer 60 and reacts chemically with the filling layer 60, increasing the surface tension of the filling layer 60. At the same time, it reacts chemically with the interface layer. Under the combined action of physical and chemical effects, the filling layer 60 decomposes, thereby causing the second back electrode layer 52 above the interface layer to detach.

[0161] In some alternative embodiments, the intermediate component structure is placed in a stripping solution and subjected to ultrasonic treatment to remove the filling layer 60 and the first back electrode layer 51 corresponding to the position of the P3 laser groove 83, forming a groove 90; the groove 90 separates the second back electrode layers 52 on both sides.

[0162] In some optional embodiments, the ultrasonic treatment time is 1 min to 10 min. The method for preparing curved cadmium telluride thin-film photovoltaic modules provided in this embodiment involves placing the intermediate module structure in a film removal solution and performing ultrasonic treatment to remove the filling layer 60 and the first back electrode layer 51 corresponding to the P3 laser groove 83 position, forming a groove 90; the groove 90 separates the second back electrode layers 52 on both sides. The concentration of the film removal solution is 1% to 100%, the temperature is 20℃ to 100℃, and the ultrasonic treatment time is 1 min to 10 min, which can improve the decomposition rate of the filling layer 60, thereby improving the film removal efficiency.

[0163] like Figure 2 As shown, the present invention also provides a detailed flowchart of a method for preparing a curved cadmium telluride thin-film photovoltaic module, including but not limited to steps S201 to S210.

[0164] Step S201: A glass substrate 10 is provided, and a transparent conductive layer 20 and a battery layer 30 are sequentially deposited from bottom to top on one side surface of the glass substrate 10.

[0165] In practice, the material and thickness of the glass substrate 10 can be set according to requirements; the material of the battery layer 30 is CdTe, CdSTe, CdSeTe, CdMgTe, CdZnTe, CdSSeTe or CdZnSSeTe.

[0166] In step S202, a P1 laser groove 81 is formed by first laser etching of the transparent conductive layer 20 and the battery layer 30; the P1 laser groove 81 penetrates the transparent conductive layer 20 and the battery layer 30, such as... Figure 3 As shown.

[0167] Step S203: Fill the P1 laser groove 81 with the first filling material, such as... Figure 4 As shown.

[0168] In practice, the insulating material is SiO2, Si3N4, or Al2O3. The thickness of the insulating material is at least greater than or equal to the thickness of the transparent conductive layer 20.

[0169] Step S204: A P2 laser groove 82 is formed by laser etching the battery layer 30; the P2 laser groove 82 penetrates the battery layer 30, such as... Figure 5 As shown.

[0170] In step S205, a contact layer 40 is formed on the side of the battery layer 30 facing away from the transparent conductive layer 20. The contact layer 40 also covers the inner wall of the P2 laser groove 82, such as... Figure 6 As shown.

[0171] In specific implementation, the material of the contact layer 40 is Pd, Ag, Cu, Ni, Ti, selenium oxide, ZnTe or CdZnTe; the thickness of the contact layer 40 is 1nm to 20nm; the contact layer 40 is suitable for preparation by electroplating, electroless plating, sputtering or evaporation processes.

[0172] In step S206, a third laser etching process is used to etch the contact layer 40 and the battery layer 30 to form a P3 laser groove 83; the P3 laser groove 83 penetrates the contact layer 40 and the battery layer 30, such as... Figure 7 As shown.

[0173] Step S207: A filling layer 60 is formed in the P3 laser groove 83, as shown below. Figure 8 As shown; the contact layer 40 exposes the surface of the filling layer 60 inside the P3 laser slot 83 to obtain the intermediate component structure; the filling layer 60 is the sacrificial layer 61.

[0174] In specific implementations, the thickness of the filler layer 60 is 20 nm to 10 μm; the filler layer 60 is suitable for preparation by sputtering, evaporation, roll coating, or printing processes. The material of the filler layer 60 is an oxide material, a photoresist material, a ceramic material, or a metal material; oxide materials include ZnO, MgZnO, or MgO; ceramic materials include SiO2, Si3N4, or Al2O3; and metal materials include Cr or Al.

[0175] Step S208 involves performing a hot bending process and a Cl process on the intermediate component structure.

[0176] Step S209: Forming a back electrode layer, which includes a first back electrode layer 51 and a second back electrode layer 52; wherein, the second back electrode layer 52 is located on the surface of the contact layer 40 facing away from the battery layer 30 and fills the P2 laser groove 82; the first back electrode layer 51 is located on the surface of the filling layer 60 inside the P3 laser groove 83; the porosity of the first back electrode layer 51 is greater than that of the second back electrode layer 52; the thickness of the first back electrode layer 51 is less than that of the second back electrode layer 52, such as... Figure 9 As shown.

[0177] In specific implementation, the thickness ratio of the first back electrode layer 51 and the second back electrode layer 52 is less than 1:10; the thickness of the second back electrode layer 52 is 50nm to 200nm, and the porosity is <10%; the first back electrode layer 51 is a porous or discontinuous layer with a porosity >30%; the material of the back electrode layer is Mo, Ni, Ti, and the corresponding nitrides or nitrogen oxides.

[0178] In step S210, a stripping solution is used to remove the filling layer 60 inside the P3 laser groove 83 through the first back electrode layer 51, and the first back electrode layer 51 located on the surface of the filling layer 60 inside the P3 laser groove 83 is also removed, forming a groove 90. The groove 90 penetrates the second back electrode layer 52, the contact layer 40, and the battery layer 30, as shown below. Figure 10 As shown.

[0179] In practice, the film removal solution contains a material that can corrode the filler layer 60; the film removal solution is an acidic solution, an alkaline solution, or an organic solvent; the acidic solution includes phosphoric acid, sulfuric acid, acetic acid, or hydrofluoric acid; the alkaline solution includes sodium hydroxide, potassium hydroxide, ferric chloride, or hydrogen peroxide; the organic solvent includes ethanol, acetone, methyl pyrrolidone, or ethanolamine; the concentration of the film removal solution is 1% to 100%, and the temperature is 20℃ to 100℃.

[0180] like Figure 11 As shown, the present invention also provides a detailed flowchart of another method for preparing curved cadmium telluride thin-film photovoltaic modules, including but not limited to steps S301 to S309.

[0181] Step S301: A glass substrate 10 is provided, and a transparent conductive layer 20, a filling layer 60 and a battery layer 30 are deposited sequentially from bottom to top on one side surface of the glass substrate 10; the filling layer 60 is a buffer layer 62.

[0182] In specific implementation, the material and thickness of the glass substrate 10 can be set according to requirements, and the material of the battery layer 30 can be CdTe, CdSTe, CdSeTe, CdMgTe, CdZnTe, CdSSeTe or CdZnSSeTe.

[0183] In step S302, a P1 laser groove 81 is formed by first laser etching of the transparent conductive layer 20 and the battery layer 30; the P1 laser groove 81 penetrates the transparent conductive layer 20 and the battery layer 30, such as... Figure 12 As shown.

[0184] Step S303: Fill the P1 laser groove 81 with the first filling material, such as... Figure 13 As shown.

[0185] In practice, the insulating material is SiO2, Si3N4, or Al2O3. The thickness of the insulating material is at least greater than or equal to the thickness of the transparent conductive layer 20.

[0186] Step S304: A P2 laser groove 82 is formed using the second laser etching buffer layer 62 and the battery layer 30; the P2 laser groove 82 penetrates the buffer layer 62 and the battery layer 30, as shown below. Figure 14 As shown.

[0187] In step S305, a contact layer 40 is formed on the side of the battery layer 30 facing away from the transparent conductive layer 20. The contact layer 40 also covers the inner wall of the P2 laser groove 82, such as... Figure 15 As shown.

[0188] In specific implementation, the material of the contact layer 40 is Pd, Ag, Cu, Ni, Ti, selenium oxide, ZnTe or CdZnTe; the thickness of the contact layer 40 is 1nm to 30nm; the contact layer 40 is suitable for preparation by electroplating, electroless plating, sputtering or evaporation processes.

[0189] In step S306, a third laser etching process is used to etch the contact layer 40 and the battery layer 30 to form a P3 laser groove 83. The P3 laser groove 83 penetrates the contact layer 40 and the battery layer 30, and exposes the filling layer 60, as shown below. Figure 16 As shown; the bottom of the P3 laser groove 83 is a filling layer 60; thus, the intermediate component structure is obtained.

[0190] In specific implementations, the thickness of the filler layer 60 is 30 nm to 10 μm; the filler layer 60 is suitable for preparation by sputtering, evaporation, roll coating, or printing processes. The material of the filler layer 60 is a group II-VI compound material; the material of the filler layer 60 is CdS, CdS:O, CdSe, CdSe:O, or MgTe.

[0191] Step S307 involves performing a hot bending process and a Cl process on the intermediate component structure.

[0192] Step S308: Forming a back electrode layer, which includes a first back electrode layer 51 and a second back electrode layer 52; wherein, the second back electrode layer 52 is located on the surface of the contact layer 40 facing away from the battery layer 30 and fills the P2 laser groove 82; the first back electrode layer 51 is located on the surface of the filling layer 60 at the bottom of the P3 laser groove 83; the porosity of the first back electrode layer 51 is greater than that of the second back electrode layer 52; the thickness of the first back electrode layer 51 is less than that of the second back electrode layer 52, such as... Figure 17 As shown.

[0193] In specific implementation, the thickness ratio of the first back electrode layer 51 and the second back electrode layer 52 is less than 1:10; the thickness of the second back electrode layer 52 is 50nm to 300nm, and the porosity is <10%; the first back electrode layer 51 is a porous or discontinuous layer with a porosity >30%; the material of the back electrode layer is Mo, Ni, Ti, and the corresponding nitrides or nitrogen oxides.

[0194] Step S309: Using a film removal solution, the filling layer 60 corresponding to the bottom of the P3 laser groove 83 is removed through the first back electrode layer 51, and the first back electrode layer 51 on the surface of the filling layer 60 at the bottom of the P3 laser groove 83 is also removed, forming a groove 90. The filling layers 60 on both sides of the groove 90 are retained. Figure 18 As shown.

[0195] In practice, the film removal solution contains a material that can corrode the filler layer 60; the film removal solution is an acidic solution, an alkaline solution, or an organic solvent; the acidic solution includes phosphoric acid, sulfuric acid, acetic acid, or hydrofluoric acid; the alkaline solution includes sodium hydroxide, potassium hydroxide, ferric chloride, or hydrogen peroxide; the organic solvent includes ethanol, acetone, methyl pyrrolidone, or ethanolamine; the concentration of the film removal solution is 1% to 100%, and the temperature is 20℃ to 100℃.

[0196] To verify the effectiveness of the method for fabricating curved cadmium telluride thin-film photovoltaic modules provided by this invention, this application provides Example 1, Example 2, and Comparative Example 1 to fabricate different curved cadmium telluride thin-film photovoltaic modules. Example 1, through... Figure 2 Prepared by the method shown. Figure 9 This is a schematic diagram of the curved cadmium telluride thin-film photovoltaic module obtained through Example 1. Example 2 is obtained through... Figure 10Prepared by the method shown. Figure 18 This is a schematic diagram of the curved cadmium telluride thin-film photovoltaic module obtained through Example 1. Comparative Example 1 is a conventional photovoltaic module fabrication method, in which P1 laser groove and P2 laser groove are formed first, and then P3 laser groove is formed after hot bending.

[0197] The preparation method provided in Comparative Example 1 includes: providing an ultra-white soda-lime glass substrate with a thickness of 2 mm to 3.2 mm; depositing a SnO2:F / SnO2 (FTO) transparent conductive layer with a thickness of 200 nm to 500 nm on the glass substrate; depositing a CdSTe or CdSeTe absorption layer with a thickness of 2 μm to 5 μm and a compositionally gradually varying thickness on the FTO transparent conductive layer; performing a first laser treatment (P1) to etch the transparent conductive layer and the battery layer to form a P1 laser groove; filling the P1 laser groove location with a SiO2 high-temperature resistant insulating material with a thickness of 0.1 μm to 7 μm; performing a second laser treatment (P2) to etch the battery layer to form a P2 laser groove; and sputtering to deposit a 100 nm thick layer. The process involves a Ni metal layer, followed by glass hot bending at 500℃–700℃ to form a regular shape with a curvature radius >10m. This is followed by Cl treatment at 400℃–500℃, surface cleaning, and a third laser treatment (P3) to etch the metal electrode layer, creating a P3 laser groove. The hot-bent hyperbolic cadmium telluride module product prepared in this comparative example exhibits a regular and uniform shape with a curvature radius >10m, primarily due to limitations imposed by the current market's limitations in the processing capabilities of curved surface laser etching equipment.

[0198] Example 1 provides a fabrication method comprising: providing an ultra-white soda-lime glass substrate with a thickness of 2 mm to 3.2 mm; depositing a SnO2:F / SnO2 (FTO) transparent conductive layer with a thickness of 200 nm to 500 nm on the glass substrate; depositing a CdSTe or CdSeTe absorption layer (i.e., a battery layer) with a compositionally gradually varying thickness of 2 μm to 5 μm on the FTO transparent conductive layer; performing a first laser processing (P1) to etch the transparent conductive layer and the battery layer to form a P1 laser groove; filling the P1 laser groove location with a SiO2 high-temperature resistant insulating material with a thickness of 0.1 μm to 7 μm; performing a second laser processing (P2) to etch the battery layer to form a P2 laser groove; and depositing a Pd contact layer with a thickness of 1 nm to 2 nm, the contact layer simultaneously covering the battery layer and the P2 laser groove. The process involves a third laser treatment (P3) to etch the battery layer and contact layer, forming a P3 laser groove. The laser groove is then filled with a 100nm CdSe filler layer (i.e., a sacrificial layer). Next, the glass is hot-bent at 500℃–700℃, resulting in a curvature radius <1m and an irregular shape. A Cl treatment at 400℃–500℃ is then performed. The surface is cleaned. An electroplating process is then used to deposit a first back electrode layer and a second back electrode layer. The first back electrode layer is a 10nm thick Ni layer with a porosity >50%, while the second back electrode layer is a 100nm thick Ni layer with a porosity <10%. Finally, a 10% hydrochloric acid solution is used to etch the CdSe filler layer and the first back electrode layer, forming a groove. This groove allows for the disconnection and insulation between the first back electrode layers on both sides of the P3 laser groove.

[0199] Example 2 provides a fabrication method comprising: providing an ultra-white soda-lime glass substrate with a thickness of 2 mm to 3.2 mm; depositing a SnO2:F / SnO2 (FTO) transparent conductive layer with a thickness of 200 nm to 500 nm on the glass substrate; depositing a ZnO filling layer (i.e., a buffer layer) with a thickness of 100 nm on the FTO transparent conductive layer 2; depositing a CdSTe or CdSeTe absorption layer (i.e., a battery layer) with a compositionally gradually varying thickness of 2 μm to 5 μm on the surface of the ZnO filling layer; performing a first laser processing (P1) to etch the transparent conductive layer, the filling layer, and the battery layer to form a P1 laser groove; filling the P1 laser groove location with a Si3N4 high-temperature resistant insulating material with a thickness of 0.5 μm to 4 μm; and performing a second laser processing (P2) to etch the filling layer and the battery layer to form a P2 laser groove. A Ni contact layer with a thickness of 1 nm to 2 nm is deposited, which simultaneously covers the battery layer and the P2 laser groove. A third laser treatment (P3) is performed to etch the battery layer and the contact layer, forming the laser groove and exposing the filling layer. The glass is then hot-bent at 500℃ to 700℃ to form an irregular shape with a curvature radius of <1 m. The glass is then treated with Cl at 400℃ to 500℃. The surface is then cleaned. A first back electrode layer and a second back electrode layer are deposited, wherein the first back electrode layer is a Ni layer with a thickness of 5 nm and a porosity of >60%, and the second back electrode layer is a Ni layer with a thickness of 150 nm and a porosity of <5%. Finally, the ZnO filling layer and the first back electrode layer are removed by etching with a 10% phosphoric acid solution to form a groove. This groove can disconnect and insulate the first back electrode layers on both sides of the P3 laser groove.

[0200] Compared to Comparative Example 1, the fabrication methods provided in Examples 1 and 2 complete all three laser integration processes before high-temperature hot bending, thereby avoiding the equipment and process requirements and limitations associated with curved surface laser processing and enabling the fabrication of curved photovoltaic modules of arbitrary shapes. Examples 1 and 2 can achieve a curvature radius of less than 1m after hot bending, resulting in irregular module shapes, which can improve the design flexibility, stability, reliability, and module efficiency of curved cadmium telluride thin-film modules.

[0201] This embodiment also provides a curved cadmium telluride thin-film photovoltaic module, such as... Figure 10 As shown, the curved cadmium telluride thin-film photovoltaic module includes:

[0202] A glass substrate 10, a transparent conductive layer 20, a battery layer 30, a contact layer 40, and a second back electrode layer 52 are stacked sequentially.

[0203] P1 laser groove 81 penetrates the transparent conductive layer 20 and the battery layer 30. The filling material of P1 laser groove 81 is an insulating material.

[0204] P2 laser slot 82, penetrating the battery layer 30;

[0205] The groove 90 penetrates the second back electrode layer 52, the contact layer 40 and the battery layer 30, and exposes the surface of the transparent conductive layer 20.

[0206] The contact layer 40 and the back electrode layer also fill the P2 laser groove 82 and cover the surface of the P1 laser groove 81.

[0207] The curved cadmium telluride thin-film photovoltaic module provided in this embodiment can achieve separation and insulation of the contact layer and the second back electrode layer on both sides of the groove by setting the groove; at the same time, the curved cadmium telluride thin-film photovoltaic module can be of any curved shape, which improves the design flexibility, stability, reliability and module efficiency of the curved cadmium telluride thin-film module.

[0208] In some alternative implementations, such as Figure 18 As shown, a buffer layer 62 is also provided between the transparent conductive layer 20 and the battery layer 30;

[0209] P1 laser groove 81 penetrates the transparent conductive layer 20, buffer layer 62 and battery layer 30;

[0210] P2 laser slot 82 penetrates buffer layer 62 and battery layer 30;

[0211] The groove 90 penetrates the buffer layer 62, the battery layer 30, the contact layer 40, and the battery layer 30.

[0212] In some alternative embodiments, the material of the buffer layer 62 is ZnO, MgZnO, ZnSO, ZnS, or CdZnS;

[0213] The material of the contact layer 40 is Pd, Ag, Cu, Ni, Ti, selenium oxide, ZnTe, or CdZnTe;

[0214] The thickness of the contact layer 40 is 1 nm to 20 nm;

[0215] The insulating material is SiO2, Si3N4 or Al2O3;

[0216] The material of the battery layer 30 is CdTe, CdSTe, CdSeTe, CdMgTe, CdZnTe, CdSSeTe, or CdZnSSeTe.

[0217] In the description of this specification, the references to terms such as "this embodiment," "an embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, those skilled in the art can combine and integrate the different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of the present invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0218] The above description does not provide detailed explanations of the technical aspects of each layer's patterning, etching, etc. However, those skilled in the art should understand that various technical means can be used to form layers and regions of the desired shape. Furthermore, to form the same structure, those skilled in the art can also design methods that are not entirely identical to those described above. Additionally, although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination.

[0219] The above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described above, and various obvious changes, readjustments, combinations, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention. The scope of protection of the present invention is determined by the scope of the appended claims.

Claims

1. A method for preparing a curved cadmium telluride thin-film photovoltaic module, characterized in that, include: A glass substrate is provided, wherein a transparent conductive layer and a battery layer are sequentially deposited from bottom to top on one side surface of the glass substrate; A P1 laser groove is formed, which penetrates the transparent conductive layer and the battery layer, and the filling material of the P1 laser groove is an insulating material; A P2 laser groove and a contact layer are formed sequentially; the P2 laser groove penetrates the battery layer; the contact layer is located on the surface of the battery layer and covers the inner wall of the P2 laser groove. A P3 laser groove is formed, which penetrates the contact layer and the battery layer, and the interior or bottom of the P3 laser groove is a filling layer. The contact layer exposes the surface of the filling layer inside or at the bottom of the P3 laser groove, thus obtaining an intermediate component structure. The intermediate component structure is subjected to a hot bending process and a Cl process. A back electrode layer is formed, the back electrode layer including a first back electrode layer and a second back electrode layer; wherein, the second back electrode layer is located on the surface of the contact layer opposite to the battery layer and fills the P2 laser groove; the first back electrode layer is located inside or on the surface of the filling layer at the bottom of the P3 laser groove; the porosity of the first back electrode layer is greater than that of the second back electrode layer; the thickness of the first back electrode layer is less than that of the second back electrode layer. A stripping solution is used to remove the filling layer and the first back electrode layer corresponding to the P3 laser slot position through the first back electrode layer, forming a groove that penetrates the second back electrode layer, the contact layer, and the battery layer.

2. The method for preparing a curved cadmium telluride thin-film photovoltaic module according to claim 1, characterized in that, The step of sequentially forming the P2 laser groove and the contact layer includes: The battery layer is etched using a second laser to form a P2 laser groove; A contact layer is formed on the side of the battery layer opposite to the transparent conductive layer, and the contact layer also covers the inner wall of the P2 laser groove.

3. The method for preparing a curved cadmium telluride thin-film photovoltaic module according to claim 2, characterized in that, The filling layer is a sacrificial layer; The step of forming the P3 laser groove includes: The contact layer and the battery layer are etched using a third laser to form a P3 laser groove; A filling layer is formed inside the P3 laser groove; the contact layer exposes the surface of the filling layer inside the P3 laser groove.

4. The method for preparing a curved cadmium telluride thin-film photovoltaic module according to claim 3, characterized in that, The first back electrode layer is located on the surface of the filling layer inside the P3 laser slot; The step of forming the groove includes: The filling layer inside the P3 laser groove is removed by using a stripping solution through the first back electrode layer, and the first back electrode layer located on the surface of the filling layer inside the P3 laser groove is removed to form a groove that penetrates the second back electrode layer, the contact layer and the battery layer.

5. The method for preparing a curved cadmium telluride thin-film photovoltaic module according to claim 4, characterized in that, The filling layer is made of oxide materials, photoresist materials, ceramic materials, metal materials, or II-VI group compound materials; The oxide material includes ZnO, MgZnO, or MgO; The ceramic material includes SiO2, Si3N4, or Al2O3; The metallic material includes Cr or Al; The group II-VI compound materials include CdS, CdS:O, CdSe, CdSe:O, and MgTe.

6. The method for preparing a curved cadmium telluride thin-film photovoltaic module according to claim 2, characterized in that, The filling layer is a buffer layer; The step of sequentially depositing a transparent conductive layer and a battery layer on the glass substrate includes: A transparent conductive layer, a filler layer, and a battery layer are sequentially deposited on the glass substrate. The step of forming the P2 laser groove includes: A P2 laser groove is formed by etching the filler layer and the battery layer using a second laser; the P2 laser groove penetrates the filler layer and the battery layer. The step of forming the P3 laser groove includes: The contact layer and the battery layer are etched using a third laser to form a P3 laser groove; the P3 laser groove penetrates the battery layer and exposes the filling layer; the bottom of the P3 laser groove is the filling layer.

7. The method for preparing a curved cadmium telluride thin-film photovoltaic module according to claim 6, characterized in that, The first back electrode layer is located on the surface of the filling layer at the bottom of the P3 laser slot; The step of forming the groove includes: The filler layer corresponding to the bottom of the P3 laser groove is removed by using a membrane removal solution through the first back electrode layer, and the first back electrode layer on the surface of the filler layer at the bottom of the P3 laser groove is removed to form a groove, while the filler layer on both sides of the groove is retained.

8. The method for preparing a curved cadmium telluride thin-film photovoltaic module according to claim 7, characterized in that, The filling layer is made of ZnO, MgZnO, ZnSO, ZnS, or CdZnS.

9. The method for preparing a curved cadmium telluride thin-film photovoltaic module according to claim 1, characterized in that, The thickness ratio of the first back electrode layer to the second back electrode layer is less than 1:10; The thickness of the second back electrode layer is 50nm to 200nm, and the porosity of the second back electrode layer is <10%. The first back electrode layer is a porous or discontinuous layer, and the porosity of the second back electrode layer is >30%. The material of the back electrode layer is Mo, Ni, Ti, and the corresponding nitrides or nitrogen oxides; The first back electrode layer and the second back electrode layer are suitable for preparation by electroplating, electroless plating, sputtering or evaporation processes; The thickness of the filling layer is 20 nm to 10 μm; The filler layer is suitable for preparation by sputtering, evaporation, roll coating or printing processes; The contact layer material is Pd, Ag, Cu, Ni, Ti, selenium oxide, ZnTe, or CdZnTe; The thickness of the contact layer is 1nm to 20nm; The contact layer is suitable for preparation by electroplating, electroless plating, sputtering or evaporation processes; The insulating material is SiO2, Si3N4 or Al2O3; The battery layer is made of CdTe, CdSTe, CdSeTe, CdMgTe, CdZnTe, CdSSeTe, or CdZnSSeTe.

10. The method for preparing a curved cadmium telluride thin-film photovoltaic module according to claim 1, characterized in that, The membrane removal solution contains a material that can corrode the filler layer; The membrane removal solution is an acidic solution, an alkaline solution, or an organic solvent; The acidic solution includes phosphoric acid, sulfuric acid, acetic acid, or hydrofluoric acid; The alkaline solution includes sodium hydroxide, potassium hydroxide, ferric chloride, or hydrogen peroxide; The organic solvent includes ethanol, acetone, methyl pyrrolidone, or ethanolamino; The concentration of the membrane removal solution is 1% to 100%, and the temperature is 20℃ to 100℃.

11. A curved cadmium telluride thin-film photovoltaic module, characterized in that, include: A glass substrate, a transparent conductive layer, a battery layer, a contact layer, and a second back electrode layer are stacked in sequence. The P1 laser groove penetrates the transparent conductive layer and the battery layer, and the filling material of the P1 laser groove is an insulating material; P2 laser groove, penetrating the battery layer; A groove that penetrates the second back electrode layer, the contact layer, and the battery layer, and exposes the surface of the transparent conductive layer; The contact layer and the back electrode layer also fill the P2 laser groove and cover the surface of the P1 laser groove.

12. The curved cadmium telluride thin-film photovoltaic module according to claim 11, characterized in that, A buffer layer is also provided between the transparent conductive layer and the battery layer; The P1 laser groove penetrates the transparent conductive layer, the buffer layer, and the battery layer; The P2 laser groove penetrates the buffer layer and the battery layer; The groove extends through the buffer layer, the battery layer, the contact layer, and the battery layer.

Images