Curved-surface cadmium telluride film photovoltaic module and preparation method thereof

Abstract

The invention relates to the technical field of semiconductors, and discloses a curved-surface cadmium telluride film photovoltaic module and a preparation method thereof, and the preparation method comprises the steps: sequentially depositing a transparent conductive layer, a high-resistance layer and an etching layer on a glass substrate; forming a P1 laser groove penetrating through the etching layer, wherein a filling material of the P1 laser groove is a first filling material; forming a second absorption layer covering the P1 laser groove; forming a P2 laser groove penetrating through the transparent conductive layer, the high-resistance layer, the etching layer and the second absorption layer; forming a P3 laser groove penetrating through the etching layer and the second absorption layer; carrying out a hot bending treatment process; sequentially forming a back contact layer and a back electrode layer on the surface of the second absorption layer, and filling the P3 laser groove; and performing a local film removing process, and removing the second absorption layer, the back contact layer and the back electrode layer corresponding to the position of the P1 laser groove to form a groove. Integration and preparation of the cadmium telluride thin film assembly with any curved surface shape can be met, and segmentation and insulation between adjacent assembly units are achieved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a curved cadmium telluride thin-film photovoltaic module and a preparation method thereof. Background Art

[0002] Currently, there are two main methods for achieving hyperbolic curvature in CdTe modules using hot bending: the first involves pre-preparing all cell membrane layers, hot bending, and then performing Cl and Cu treatments; the second involves pre-preparing some high-temperature resistant membrane layers, hot bending, and then performing curved surface coating and integration. The first method is limited by the presence of metal back electrodes, such as Mo, which affect the Cl treatment and limit cell efficiency to only 70% to 80% of conventional modules. The second method is primarily limited by the inability of existing laser equipment to etch irregular curved surfaces. Current curved laser or mechanical etching equipment can only process hyperbolic products with simple shapes and small deformations, but cannot process complex shapes and large deformations.

[0003] Therefore, a method for preparing curved cadmium telluride thin-film photovoltaic modules is needed to avoid laser etching of the curved photovoltaic modules after thermal bending, while avoiding the obstruction and influence of the metal back electrode on the thermal bending process and the Cl treatment process. Summary of the Invention

[0004] In view of this, the present invention provides a curved cadmium telluride thin-film photovoltaic module and a preparation method thereof to solve the problems in the related art that laser equipment cannot achieve etching of irregular curved surfaces, and that the metal electrode layer blocks and affects the hot bending process and the Cl treatment process.

[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] Providing a glass substrate, and sequentially depositing a transparent conductive layer, a high-resistance layer, and an etching layer on the glass substrate;

[0007] A P1 laser groove is formed, wherein the P1 laser groove penetrates the etching layer, and the filling material of the P1 laser groove is the first filling material;

[0008] A second absorption layer is formed on the side of the etching layer facing away from the high-resistance layer; the second absorption layer covers the surface of the P1 laser groove;

[0009] forming a P2 laser groove, wherein the P2 laser groove penetrates the transparent conductive layer, the high-resistance layer, the etching layer, and the second absorption layer, and the filling material of the P2 laser groove is the second filling material;

[0010] forming a P3 laser groove, wherein the P3 laser groove penetrates the etching layer and the second absorption layer; and obtaining a first component structure;

[0011] Performing a hot bending process and a Cl treatment process on the first component structure;

[0012] forming a back contact layer and a back electrode layer in sequence on a surface of the second absorption layer facing away from the etching layer to obtain a second component structure, wherein the back contact layer and the back electrode layer are also filled with a P3 laser groove;

[0013] The second component structure is subjected to a local stripping process to remove the second absorption layer, the back contact layer and the back electrode layer corresponding to the position of the P1 laser groove to form a groove.

[0014] The present invention provides a method for preparing a curved cadmium telluride thin-film photovoltaic module. In a first aspect, a first filling material is first filled in a P1 laser groove, and a second absorption layer is formed on the surface of the P1 laser groove. Then, after forming a back contact layer and a back electrode layer, a local film removal process is performed to remove the second absorption layer, the back contact layer and the back electrode layer corresponding to the position of the P1 laser groove to form a groove, thereby separating and insulating the back contact layer and the back electrode layer on both sides of the P1 laser groove, thereby realizing the division and insulation between adjacent module units. A new metal layer separation and insulation method based on the combination of a laser groove pre-buried layer process and a selective film removal process is developed, thereby realizing the replacement of the third laser process in the traditional module integration process. Secondly, by forming the P1 laser groove, the P2 laser groove and the P3 laser groove before the hot bending process, and completing all laser etching integration processes before hot bending to form a curved photovoltaic module, it is possible to avoid etching the curved photovoltaic module, thereby avoiding the need and restrictions on curved laser equipment and processes, and meeting the integration and preparation of cadmium telluride thin-film modules with arbitrary curved shapes; thirdly, by forming the back electrode layer after the hot bending process, it is possible to avoid the back electrode layer blocking and affecting the hot bending process and the Cl treatment process, thereby improving the effects of the hot bending process and the Cl treatment process, and thereby improving the efficiency of the module.

[0015] In an optional embodiment, the step of forming the P1 laser groove includes:

[0016] Etching the etched layer using a first laser to form a P1 laser groove;

[0017] Filling the P1 laser groove with a first filling material;

[0018] The steps of forming the P2 laser groove include:

[0019] A second laser is used to etch the transparent conductive layer, the high-resistance layer, the etching layer, and the second absorption layer to form a P2 laser groove;

[0020] The P2 laser trench is filled with a second filling material.

[0021] In an optional embodiment, in the step of forming the second absorption layer, the second absorption layer contacts the first filling material in the P1 laser groove, and the stress between the second absorption layer and the first filling material is greater than 0.5 GPa; an interface layer is formed between the second absorption layer and the first filling material;

[0022] In the local stripping process, the interface layer between the second absorption layer and the first filling material corresponding to the P1 laser groove position is decomposed, and the second absorption layer, back contact layer and back electrode layer corresponding to the P1 laser groove position are removed to form a groove.

[0023] The present invention provides a method for preparing a curved cadmium telluride thin-film photovoltaic module, in which a second absorption layer is formed on the surface of a P1 laser groove, which contacts the first filling material in the P1 laser groove and forms an interface layer. The second absorption layer and the first filling material have high stress and low bonding force, so that in a local film removal process, the interface layer between the second absorption layer corresponding to the position of the P1 laser groove and the first filling material is decomposed, thereby removing the second absorption layer, back contact layer and back electrode layer corresponding to the position of the P1 laser groove to form a groove, thereby realizing the segmentation and insulation of the back contact layer / back electrode layer on both sides of the P1 laser groove.

[0024] In an optional embodiment, the step of forming the second absorption layer includes:

[0025] A second window layer is formed on the surface of the etching layer facing away from the high-resistance layer; the second window layer covers the surface of the P1 laser groove;

[0026] forming a second absorption layer on a surface of the second window layer facing away from the etching layer;

[0027] The steps of forming the groove include:

[0028] Performing a local stripping process on the second component structure to remove the second window layer, the second absorption layer, the back contact layer, and the back electrode layer corresponding to the position of the P1 laser groove to form a groove;

[0029] In the step of forming the second window layer, the second window layer contacts the first filling material in the P1 laser groove, and the stress between the second window layer and the first filling material is greater than 0.5 GPa; an interface layer is formed between the second window layer and the first filling material;

[0030] In the local film removal process, the interface layer between the second window layer corresponding to the P1 laser groove position and the first filling material is decomposed, and the second window layer, the second absorption layer, the back contact layer and the back electrode layer corresponding to the P1 laser groove position are removed to form a groove.

[0031] The present invention provides a method for preparing a curved cadmium telluride thin-film photovoltaic module, in which a second window layer is formed on the surface of a P1 laser groove, which contacts the first filling material in the P1 laser groove and forms an interface layer. The second window layer and the first filling material have high stress and low bonding force, so that in a local film removal process, the interface layer between the second window layer corresponding to the position of the P1 laser groove and the first filling material is decomposed, thereby removing the second window, the second absorption layer, the back contact layer and the back electrode layer corresponding to the position of the P1 laser groove to form a groove, thereby realizing the segmentation and insulation of the back contact layer / back electrode layer on both sides of the P1 laser groove.

[0032] In an optional embodiment, the first filling material includes one or two layers of Al2O3, SiO2, Si3N4, ZrO2, NaCl, MgTe, Ni, Mo, and Cr;

[0033] The second filling material is an insulating material;

[0034] The material of the second window layer is CdS, CdSe, CdS:O, CdSe:O, CdSSe or CdSSeO;

[0035] The material of the second absorption layer is CdTe, CdSTe, CdSeTe, CdMgTe, CdZnTe, CdSSeTe or CdZnSSeTe.

[0036] The present invention provides a method for preparing a curved cadmium telluride thin-film photovoltaic module, wherein the first filling material includes one or two layers of Al2O3, SiO2, Si3N4, ZrO2, NaCl, MgTe, Ni, Mo, and Cr; the material of the second window layer is CdS, CdSe, CdS:O, CdSe:O, CdSSe, or CdSSeO; the material of the second absorption layer is CdTe, CdSTe, CdSeTe, CdMgTe, CdZnTe, CdSSeTe, or CdZnSSeTe ; The second window layer or the second absorption layer can contact the first filling material in the P1 laser groove and form an interface layer. The second window layer or the second absorption layer and the first filling material have high stress and low bonding force, so that the interface layer between the second window layer corresponding to the P1 laser groove position and the first filling material can be decomposed through a local stripping process, and then the second window, the second absorption layer, the back contact layer and the back electrode layer corresponding to the P1 laser groove position are removed to form a groove, thereby realizing the segmentation and insulation of the back contact layer / back electrode layer on both sides of the P1 laser groove.

[0037] In an optional embodiment, the local film removal process includes:

[0038] The second component structure is placed in a local film-removing solution and is subjected to ultrasonic treatment to remove the second absorption layer, the back contact layer and the back electrode layer corresponding to the position of the P1 laser groove, thereby forming a groove; the groove separates the back contact layer and the back electrode layer on both sides of the P1 laser groove;

[0039] The local film-removing solution comprises an acid solution or an alkali solution.

[0040] The temperature of the local film-removing solution is 30-100 DEG C; and the ultrasonic treatment time is 1-10 minutes.

[0041] The preparation method of the curved cadmium telluride thin film photovoltaic component provided by the application can decompose the interface layer between the second absorption layer and the first filling material at a high speed, thereby improving the film-removing efficiency.

[0042] In an alternative embodiment, the material of the back contact layer is metal; and the material of the back electrode layer is metal.

[0043] The step of forming the back contact layer and the back electrode layer comprises:

[0044] The first component structure is subjected to surface acid treatment.

[0045] The back contact layer is formed on the surface of the second absorption layer opposite to the etching layer through a Cu treatment process; and the back contact layer also covers the inner wall of the P3 laser groove.

[0046] The back electrode layer is formed on the surface of the back contact layer opposite to the second absorption layer; and the back electrode layer also fills the P3 laser groove.

[0047] The preparation method of the curved cadmium telluride thin film photovoltaic component provided by the application can avoid the blockage and influence of the back electrode layer on the Cl treatment process and the Cu treatment process, improve the effect of the heat bending treatment process and the Cl treatment process, and thereby improve the efficiency of the component; finally, the local film-removing process is used to remove the second absorption layer, the back contact layer and the back electrode layer corresponding to the position of the P1 laser groove, thereby forming a groove and realizing the separation and insulation of the back contact layer and the back electrode layer on both sides of the P1 laser groove.

[0048] In a second aspect, the application provides a curved cadmium telluride thin film photovoltaic component, which comprises:

[0049] The glass substrate, the transparent conductive layer, the high-resistance layer, the etching layer, the second absorption layer, the back contact layer and the back electrode layer are sequentially stacked.

[0050] A P1 laser groove, wherein the P1 laser groove penetrates the etching layer, and the filling material of the P1 laser groove is a first filling material;

[0051] A groove penetrates the second absorption layer, the back contact layer, and the back electrode layer corresponding to the position of the P1 laser groove, and exposes the surface of the P1 laser groove;

[0052] A P2 laser groove, wherein the P2 laser groove penetrates the transparent conductive layer, the high-resistance layer, the etching layer, and the second absorption layer, and the filling material of the P2 laser groove is the second filling material;

[0053] P3 laser groove, the P3 laser groove penetrates the etching layer and the second absorption layer;

[0054] The back contact layer and the back electrode layer also fill the P3 laser groove and cover the surface of the P2 laser groove and the surface of the P3 laser groove.

[0055] The curved cadmium telluride thin-film photovoltaic module provided by the present invention can achieve separation and insulation of the back contact layer and the back electrode layer on both sides of the P1 laser groove by providing a groove that passes through the second absorption layer, the back contact layer and the back electrode layer corresponding to the position of the P1 laser groove and exposes the surface of the P1 laser groove; at the same time, the curved cadmium telluride thin-film photovoltaic module can have any curved shape.

[0056] In an optional embodiment, the first filling material includes one or two layers of Al2O3, SiO2, Si3N4, ZrO2, NaCl, MgTe, Ni, Mo, and Cr;

[0057] The second filling material is an insulating material;

[0058] The material of the second absorption layer is CdTe, CdSTe, CdSeTe, CdMgTe, CdZnTe, CdSSeTe or CdZnSSeTe.

[0059] In an optional embodiment, the curved cadmium telluride thin-film photovoltaic module further includes:

[0060] The second window layer is located on the surface of the etching layer facing away from the high-resistance layer; the second window layer is located between the etching layer and the second absorption layer; the second window layer covers the surface of the P1 laser groove;

[0061] The P3 laser groove penetrates the etching layer, the second window layer and the second absorption layer;

[0062] The groove passes through the second window layer, the second absorption layer, the back contact layer and the back electrode layer corresponding to the position of the P1 laser groove;

[0063] The material of the second window layer is CdS, CdSe, CdS:O, CdSe:O, CdSSe or CdSSeO;

[0064] The thickness of the second window layer is 50nm to 400nm;

[0065] The thickness of the second absorption layer is 1 μm to 4 μm.

[0066] In an optional embodiment, the material of the etching layer is a metal film material, and the metal film material is Al, Cr, ZnO or MgTe;

[0067] or:

[0068] The etching layer is a first window layer, a first absorption layer, or a first window layer / first absorption layer stack;

[0069] The material of the first window layer is CdS, CdSe, CdS:O, CdSe:O, CdSSe or CdSSeO;

[0070] The material of the first absorption layer is CdTe, CdSTe, CdSeTe, CdMgTe, CdZnTe, CdSSeTe or CdZnSSeTe;

[0071] The thickness of the first window layer is 50nm to 200nm;

[0072] The thickness of the first absorption layer is 0.3 μm to 3 μm.

[0073] In the curved cadmium telluride thin film photovoltaic module provided by the present invention, the etching layer can be a metal thin film material, or it can be a first absorption layer or a first window layer / first absorption layer stack. The etching layer is set as a first window layer / first absorption layer stack. A first absorption layer and a second absorption layer with a composition gradient can be set in the curved cadmium telluride thin film photovoltaic module to improve the light absorption effect of the photovoltaic module and thereby improve the photoelectric conversion efficiency of the photovoltaic module. BRIEF DESCRIPTION OF THE DRAWINGS

[0074] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in related technologies, the following briefly introduces the drawings required for use in the specific embodiments or related technical descriptions. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0075] Figure 1 It is a schematic flow chart of a method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0076] Figure 2 The figure is a schematic diagram of a specific process of a method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0077] Figure 3 3 is a schematic structural diagram of forming a P1 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 4 It is a structural schematic diagram of forming a P2 laser groove and a P3 laser groove in a method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0079] Figure 5 It is a structural schematic diagram of forming a back contact layer and a back electrode layer in a method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0080] Figure 6 3 is a schematic structural diagram of forming grooves in a method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0081] Figure 7 1 is a schematic diagram of a 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 8 It is a structural schematic diagram of forming a P1 laser groove, a P2 laser groove, and a P3 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 9 3 is a schematic structural diagram of forming a back contact layer and a back electrode layer in another method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0084] Figure 10 3 is a schematic structural diagram of forming grooves in another method for preparing a curved cadmium telluride thin-film photovoltaic module according to an embodiment of the present invention.

[0085] Figure 11 The figure is a schematic structural diagram of a curved cadmium telluride thin-film photovoltaic module in which the etching layer is a first window layer / first absorption layer stack according to an embodiment of the present invention.

[0086] Reference numerals:

[0087] 10. Glass substrate; 20. Transparent conductive layer; 30. High-resistance layer; 40. Etching layer; 41. First window layer; 42. First absorption layer; 51. Second window layer; 52. Second absorption layer; 60. Back contact layer; 70. Back electrode layer; 81. P1 laser groove; 82. P2 laser groove; 83. P3 laser groove; 90. Groove. DETAILED DESCRIPTION

[0088] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0089] In the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion about the concepts of the present invention. The accompanying drawings illustrate various schematic diagrams of structures according to embodiments of the present invention. These figures are not drawn to scale; certain details are exaggerated and may be omitted for clarity. The shapes of the various regions and layers shown in the figures, as well as their relative sizes and positional relationships, are merely exemplary and may deviate in practice due to manufacturing tolerances or technical limitations. Those skilled in the art may design regions / layers with different shapes, sizes, and relative positions based on actual needs. 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 intervening layer / element between them. Furthermore, if a layer / element is "on" another layer / element in one orientation, it may be "below" the other layer / element when the orientation is reversed.

[0090] Combining CdTe thin-film modules with a hot-bending process to produce curved CdTe thin-film photovoltaic modules is a very important and promising research endeavor. Currently, there are two main methods for producing curved CdTe modules using hot-bending: the first involves pre-preparing all cell film layers, performing hot-bending, and then performing Cl and Cu treatments; the second involves pre-preparing some high-temperature-resistant film layers, performing hot-bending, and then performing curved surface coating and integration. The first method is limited by the presence of a metal back electrode, such as Mo, which affects the Cl treatment and limits cell efficiency to only 70% to 80% of conventional modules. The second method is primarily limited by the inability of existing laser equipment to etch irregularly curved surfaces. Current curved laser or mechanical etching equipment can only process simple-shaped, minimally deformed hyperbolic products, but cannot process complex, heavily deformed hyperbolic products.

[0091] Therefore, a new method for preparing curved cadmium telluride thin-film photovoltaic modules is needed to avoid laser etching of the curved photovoltaic modules after hot bending, while avoiding the obstruction and influence of metal electrodes on the hot bending process and Cl treatment process.

[0092] This application primarily addresses the limitations of the second method's integration process based on traditional laser or mechanical etching, as well as the impact of the metal back electrode on Cl treatment efficiency in the first method. By designing the cell structure and adjusting the module integration and fabrication process, a new selective film removal method based on a laser trench pre-embedded layer process has been developed. This replaces the third laser process in the traditional module integration process, enabling the completion of all three laser integration processes before the high-temperature hot bending process. This eliminates the need for and limitations of curved laser equipment and processes, enabling the integration and fabrication of cadmium telluride thin-film modules with arbitrary curved shapes.

[0093] 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 S108.

[0094] In step S101 , a glass substrate 10 is provided, and a transparent conductive layer 20 , a high-resistance layer 30 , and an etching layer 40 are sequentially deposited on the glass substrate 10 .

[0095] Step S102, forming a P1 laser groove 81, the P1 laser groove 81 penetrates the etching layer 40, and the filling material of the P1 laser groove 81 is a first filling material, such as Figure 3 shown.

[0096] In step S103 , a second absorption layer 52 is formed on the side of the etching layer 40 facing away from the high-resistance layer 30 ; the second absorption layer 52 covers the surface of the P1 laser groove 81 .

[0097] Step S104, forming a P2 laser groove 82, the P2 laser groove 82 penetrates the transparent conductive layer 20, the high resistance layer 30, the etching layer 40, and the second absorption layer 52, and the filling material of the P2 laser groove 82 is the second filling material, such as Figure 4 shown.

[0098] Step S105, forming a P3 laser groove 83, the P3 laser groove 83 penetrates the etching layer 40 and the second absorption layer 52, and obtains a first component structure, such as Figure 5 shown.

[0099] Step S106, performing a thermal bending process and a Cl treatment process on the first component structure;

[0100] Step S107, a back contact layer 60 and a back electrode layer 70 are sequentially formed on the surface of the second absorption layer 52 facing away from the etching layer 40 to obtain a second component structure. The back contact layer 60 and the back electrode layer 70 are also filled with the P3 laser groove 83, as shown in FIG. Figure 5 shown.

[0101] In step S108, a local film-removing process is performed on the second component structure to remove the second absorption layer 52, the back contact layer 60 and the back electrode layer 70 corresponding to the position of the P1 laser groove 81, and a groove 90 is formed, as shown in Figure 6

[0102] In actual implementation, since the back contact layer is relatively thin, the back contact layer and the back electrode layer are sequentially filled in the P3 laser groove.

[0103] The preparation method of the curved cadmium telluride thin film photovoltaic component provided in the embodiment has the following advantages. First, the P1 laser groove is formed before the heat bending process, and all laser etching integration processes are completed before the curved photovoltaic component is formed through the heat bending process, which can avoid etching treatment on the curved photovoltaic component, and further avoid the demand and limitation of curved laser equipment and process, and can meet the integration and preparation of cadmium telluride thin film components with any curved shape. Second, the back electrode layer is formed after the heat bending process, which can avoid the blocking and influence of the back electrode layer on the heat bending process and the Cl treatment process, improve the effect of the heat bending process and the Cl treatment process, and further improve the efficiency of the component.

[0104] Therefore, the preparation method of the curved cadmium telluride thin film photovoltaic component provided in the embodiment forms the P1 laser groove before the heat bending process, forms the groove to separate the back contact layer and the back electrode after the heat bending process, realizes the separation and insulation between adjacent component units, and further realizes the replacement of the third laser process in the traditional component integration process, so that all laser etching integration processes can be completed before the curved photovoltaic component is formed through the heat bending process, etching treatment on the curved photovoltaic component is avoided, and further the demand and limitation of curved laser equipment and process are avoided, which can meet the integration and preparation of cadmium telluride thin film components with any curved shape. At the same time, the blocking and influence of the back electrode layer on the heat bending process and the Cl treatment process are avoided, the effect of the heat bending process and the Cl treatment process is improved, and the efficiency of the component is further improved.

[0105] In some optional embodiments, the step of forming the P1 laser groove 81 includes:

[0106] ​The first laser is used to etch the etched layer 40 to form a P1 laser groove 81;

[0107] Filling the P1 laser groove 81 with a first filling material;

[0108] The steps of forming the P2 laser groove 82 include:

[0109] The transparent conductive layer 20, the high resistance layer 30, the etching layer 40, and the second absorption layer 52 are etched using a second laser to form a P2 laser groove 82;

[0110] The P2 laser groove 82 is filled with a second filling material.

[0111] In some optional embodiments, during the step of forming the second absorption layer 52 , the second absorption layer 52 contacts the first filling material in the P1 laser groove 81 , and the stress between the second absorption layer 52 and the first filling material is greater than 0.5 GPa; an interface layer is formed between the second absorption layer 52 and the first filling material;

[0112] In the local stripping process, the interface layer between the second absorption layer 52 and the first filling material corresponding to the P1 laser groove 81 is decomposed, and the second absorption layer 52, the back contact layer 60 and the back electrode layer 70 corresponding to the P1 laser groove 81 are removed to form a groove 90.

[0113] The preparation method of the curved cadmium telluride thin-film photovoltaic module provided in this embodiment forms a second absorption layer on the surface of the P1 laser groove, which contacts the first filling material in the P1 laser groove and forms an interface layer. The second absorption layer and the first filling material have high stress and low bonding force, so that in the local film removal process, the interface layer between the second absorption layer corresponding to the position of the P1 laser groove and the first filling material is decomposed, so that the second absorption layer, back contact layer and back electrode layer corresponding to the position of the P1 laser groove can be removed to form a groove, thereby realizing the segmentation and insulation of the back contact layer / back electrode layer on both sides of the P1 laser groove.

[0114] In some optional embodiments, the step of forming the second absorption layer 52 includes:

[0115] A second window layer 51 is formed on the surface of the etching layer 40 facing away from the high-resistance layer 30 ; the second window layer 51 covers the surface of the P1 laser groove 81 ;

[0116] A second absorption layer 52 is formed on a surface of the second window layer 51 facing away from the etching layer 40 ;

[0117] The steps of forming the groove 90 include:

[0118] The second component structure is subjected to a local stripping process to remove the second window layer 51 , the second absorption layer 52 , the back contact layer 60 and the back electrode layer 70 corresponding to the position of the P1 laser groove 81 to form a groove 90 .

[0119] In some optional embodiments, during the step of forming the second window layer 51 , the second window layer 51 contacts the first filling material in the P1 laser groove 81 , and the stress between the second window layer 51 and the first filling material is greater than 0.5 GPa; an interface layer is formed between the second window layer 51 and the first filling material;

[0120] In the local stripping process, the interface layer between the second window layer 51 and the first filling material corresponding to the position of the P1 laser groove 81 is decomposed, and the second window layer 51, the second absorption layer 52, the back contact layer 60 and the back electrode layer 70 corresponding to the position of the P1 laser groove 81 are removed to form a groove 90.

[0121] The preparation method of the curved cadmium telluride thin-film photovoltaic module provided in this embodiment forms a second window layer on the surface of the P1 laser groove, which contacts the first filling material in the P1 laser groove and forms an interface layer. The second window layer and the first filling material have high stress and low bonding force, so that in the local film removal process, the interface layer between the second window layer corresponding to the position of the P1 laser groove and the first filling material is decomposed, so that the second window, the second absorption layer, the back contact layer and the back electrode layer corresponding to the position of the P1 laser groove can be removed to form a groove, thereby realizing the segmentation and insulation of the back contact layer / back electrode layer on both sides of the P1 laser groove.

[0122] In some optional embodiments, the first filling material includes one or two layers of Al2O3, SiO2, Si3N4, ZrO2, NaCl, MgTe, Ni, Mo, and Cr;

[0123] The second filling material is an insulating material;

[0124] The material of the second window layer 51 is CdS, CdSe, CdS:O, CdSe:O, CdSSe or CdSSeO;

[0125] The material of the second absorption layer 52 is CdTe, CdSTe, CdSeTe, CdMgTe, CdZnTe, CdSSeTe or CdZnSSeTe.

[0126] In the preparation method of the curved cadmium telluride thin-film photovoltaic module provided in this embodiment, the first filling material includes one or two layers of Al2O3, SiO2, Si3N4, ZrO2, NaCl, MgTe, Ni, Mo, and Cr; the material of the second window layer is CdS, CdSe, CdS:O, CdSe:O, CdSSe, or CdSSeO; the material of the second absorption layer is CdTe, CdSTe, CdSeTe, CdMgTe, CdZnTe, CdSSeTe, or CdZnSSeTe ; The second window layer or the second absorption layer can contact the first filling material in the P1 laser groove and form an interface layer. The second window layer or the second absorption layer and the first filling material have high stress and low bonding force, so that the interface layer between the second window layer corresponding to the P1 laser groove position and the first filling material can be decomposed through a local stripping process, and then the second window, the second absorption layer, the back contact layer and the back electrode layer corresponding to the P1 laser groove position are removed to form a groove, thereby realizing the segmentation and insulation of the back contact layer / back electrode layer on both sides of the P1 laser groove.

[0127] In some optional embodiments, the local film removal process includes:

[0128] The second component structure is placed in a local stripping solution and subjected to ultrasonic treatment to remove the second absorption layer 52, the back contact layer 60, and the back electrode layer 70 corresponding to the position of the P1 laser groove 81, thereby forming a groove 90; the groove 90 separates the back contact layer 60 and the back electrode layer 70 on both sides of the P1 laser groove 81;

[0129] Topical descaling solutions include acidic or alkaline solutions;

[0130] The temperature of the local membrane removal solution is 30° C. to 100° C.; and the ultrasonic treatment time is 1 min to 10 min.

[0131] During specific implementation, the local film removal solution penetrates into the interface layer through crystallization penetration. The local film removal solution can increase the surface tension of the interface layer and react chemically with the interface layer. Under the simultaneous action of physical and chemical effects, the interface layer is decomposed, and the second absorption layer, back contact layer and back electrode layer above the interface layer are then fallen off.

[0132] The preparation method of the curved cadmium telluride thin-film photovoltaic module provided in this embodiment places the second module structure in a local defilming solution and performs ultrasonic treatment to remove the second absorption layer, back contact layer and back electrode layer corresponding to the P1 laser groove position. The local defilming solution includes an acid solution or an alkaline solution; the temperature of the local defilming solution is 30°C to 100°C; the ultrasonic treatment time is 1min to 10min, which can increase the decomposition rate of the interface layer between the second absorption layer and the first filling material, thereby improving the defilming efficiency.

[0133] In some optional embodiments, the local film removal process includes:

[0134] The second component structure is placed in a local stripping solution and subjected to ultrasonic treatment to remove the second window layer 51, the second absorption layer 52, the back contact layer 60 and the back electrode layer 70 corresponding to the position of the P1 laser groove 81, thereby forming a groove 90; the groove 90 separates the back contact layer 60 and the back electrode layer 70 on both sides of the P1 laser groove 81;

[0135] Topical descaling solutions include acidic or alkaline solutions;

[0136] The temperature of the local membrane removal solution is 30° C. to 100° C.; and the ultrasonic treatment time is 1 min to 10 min.

[0137] During specific implementation, the local film removal solution penetrates into the interface layer through crystallization penetration. The local film removal solution can increase the surface tension of the interface layer and react chemically with the interface layer. Under the simultaneous action of physical and chemical effects, the interface layer is decomposed, and the second window layer, second absorption layer, back contact layer and back electrode layer above the interface layer are fallen off.

[0138] In some optional embodiments, the topical descaling solution includes hydrochloric acid solution, sulfuric acid solution, sodium hydroxide solution or potassium hydroxide solution.

[0139] In some optional embodiments, the material of the back contact layer 60 is metal; the material of the back electrode layer 70 is metal;

[0140] The steps of forming the back contact layer 60 and the back electrode layer 70 include:

[0141] performing a surface acid treatment on the first component structure;

[0142] A back contact layer 60 is formed on the surface of the second absorption layer 52 facing away from the etching layer 40 by a Cu treatment process; the back contact layer 60 also covers the inner wall of the P3 laser groove 83;

[0143] A back electrode layer 70 is formed on the surface of the back contact layer 60 facing away from the second absorption layer 52 ; the back electrode layer 70 also fills the P3 laser groove 83 .

[0144] The preparation method of the curved cadmium telluride thin-film photovoltaic module provided in this embodiment forms two metal layers, a back contact layer and a back electrode layer, after the hot bending process. This can avoid the back electrode layer from blocking and affecting the Cl treatment process and the Cu treatment process, improve the effects of the hot bending process and the Cl treatment process, and thus improve the efficiency of the module; finally, through a local film removal process, the second absorption layer, the back contact layer and the back electrode layer corresponding to the position of the P1 laser groove are removed to form a groove, thereby achieving separation and insulation of the back contact layer and the back electrode layer on both sides of the P1 laser groove.

[0145] In some optional embodiments, the etching layer 40 is a first window layer, a first absorption layer 42 or a first window layer / first absorption layer 42 stack;

[0146] The material of the first window layer is CdS, CdSe, CdS:O, CdSe:O, CdSSe or CdSSeO;

[0147] The material of the first absorption layer 42 is CdTe, CdSTe, CdSeTe, CdMgTe, CdZnTe, CdSSeTe or CdZnSSeTe.

[0148] In some optional embodiments, the etching layer 40 is a first window layer / first absorption layer 42 stack; the first window layer is located on the side of the high resistance layer 30 facing away from the transparent conductive layer 20; the first absorption layer 42 is located on the side of the first window layer facing away from the high resistance layer 30;

[0149] The thickness of the first window layer is 50nm to 200nm;

[0150] The thickness of the first absorption layer 42 is 0.3 μm to 3 μm.

[0151] In some optional embodiments, the material of the etching layer 40 is a metal thin film material, and the metal thin film material is Al, Cr, ZnO or MgTe.

[0152] In some optional embodiments, the metal film material is an Al film, and the first filling material is SiO2; after forming the etching layer 40 (Al film), a first laser etching is performed to form a P1 laser groove 81; the P1 laser groove 81 is filled with SiO2; and then acid corrosion is used to remove the Al / SiO2 layer outside the position of the P1 laser groove 81 to achieve selective filling of the P1 laser groove 81 with SiO2.

[0153] In the curved cadmium telluride thin-film photovoltaic module provided in this embodiment, the etching layer can be a metal thin film material, or it can be a first absorption layer or a first window layer / first absorption layer stack. The etching layer is set as a first window layer / first absorption layer stack. A first absorption layer and a second absorption layer with a composition gradient can be set in the curved cadmium telluride thin-film photovoltaic module to improve the light absorption effect of the photovoltaic module and thereby improve the photoelectric conversion efficiency of the photovoltaic module.

[0154] like Figure 2 As shown, the present invention also provides a specific flow chart of a method for preparing a curved cadmium telluride thin-film photovoltaic module, including but not limited to steps S201 to S212.

[0155] In step S201 , a glass substrate 10 is provided, and a transparent conductive layer 20 , a high-resistance layer 30 , and an etching layer 40 are sequentially deposited on the glass substrate 10 .

[0156] Step S202 : using a first laser to etch the etching layer 40 to form a P1 laser groove 81 ; the P1 laser groove 81 penetrates the etching layer 40 .

[0157] Step S203: Fill the P1 laser groove 81 with a first filling material, such as Figure 3 shown.

[0158] In a specific implementation, the first filling material includes one or two layers of Al2O3, SiO2, Si3N4, ZrO2, NaCl, MgTe, Ni, Mo, and Cr.

[0159] In step S204, a second absorption layer 52 is formed on the side of the etching layer 40 facing away from the high-resistance layer 30; the second absorption layer 52 covers the surface of the P1 laser groove 81; the second absorption layer 52 is in contact with the first filling material in the P1 laser groove 81, and the stress between the second absorption layer 52 and the first filling material is greater than 0.5 GPa; an interface layer is formed between the second absorption layer 52 and the first filling material.

[0160] In step S205 , a second laser is used to etch the transparent conductive layer 20 , the high-resistance layer 30 , the etching layer 40 , and the second absorption layer 52 to form a P2 laser groove 82 .

[0161] Step S206, fill the P2 laser groove 82 with a second filling material, such as Figure 4 shown.

[0162] Step S207, forming a P3 laser groove 83, the P3 laser groove 83 penetrates the etching layer 40 and the second absorption layer 52, and obtains a first component structure, such as Figure 4 shown.

[0163] Step S208: performing a hot bending process and a Cl treatment process on the first component structure.

[0164] Step S209: performing surface acid treatment on the first component structure.

[0165] In step S210 , a back contact layer 60 is formed on the surface of the second absorption layer 52 facing away from the etching layer 40 by a Cu treatment process; the back contact layer 60 also covers the inner wall of the P3 laser groove 83 ; the material of the back contact layer 60 is metal.

[0166] Step S211, forming a back electrode layer 70 on the surface of the back contact layer 60 facing away from the second absorption layer 52; the back electrode layer 70 also fills the P3 laser groove 83; the material of the back electrode layer 70 is metal, such as Figure 5 shown.

[0167] In step S212, the second component structure is placed in a local stripping solution and subjected to ultrasonic treatment. The interface layer between the second absorption layer 52 and the first filling material corresponding to the position of the P1 laser groove 81 is decomposed, and the second absorption layer 52, the back contact layer 60 and the back electrode layer 70 corresponding to the position of the P1 laser groove 81 are removed to form a groove 90; the groove 90 separates the back contact layer 60 and the back electrode layer 70 on both sides of the P1 laser groove 81. Figure 6 shown.

[0168] In a specific implementation, the local membrane removal solution includes hydrochloric acid solution, sulfuric acid solution, sodium hydroxide solution or potassium hydroxide solution. The temperature of the local membrane removal solution is 30° C. to 100° C.; and the ultrasonic treatment time is 1 minute to 10 minutes.

[0169] like Figure 7 As shown, the present invention also provides a specific flow chart of another method for preparing a curved cadmium telluride thin-film photovoltaic module, including but not limited to steps S301 to S308.

[0170] In step S301 , a glass substrate 10 is provided, and a transparent conductive layer 20 , a high-resistance layer 30 , and an etching layer 40 are sequentially deposited on the glass substrate 10 .

[0171] Step S302 : using a first laser to etch the etching layer 40 to form a P1 laser groove 81 ; the P1 laser groove 81 penetrates the etching layer 40 .

[0172] Step S303: Fill the P1 laser groove 81 with a first filling material, such as Figure 8 shown.

[0173] In a specific implementation, the first filling material includes one or two layers of Al2O3, SiO2, Si3N4, ZrO2, NaCl, MgTe, Ni, Mo, and Cr.

[0174] Step S304, forming a second window layer 51 on the surface of the etching layer 40 facing away from the high-resistance layer 30; the second window layer 51 covers the surface of the P1 laser groove 81; the second window layer 51 contacts the first filling material in the P1 laser groove 81, and the stress between the second window layer 51 and the first filling material is greater than 0.5GPa; an interface layer is formed between the second window layer 51 and the first filling material, such as Figure 8 shown.

[0175] In step S305 , a second absorption layer 52 is formed on the surface of the second window layer 51 facing away from the etching layer 40 .

[0176] In step S306 , a second laser is used to etch the transparent conductive layer 20 , the high-resistance layer 30 , the etching layer 40 , and the second absorption layer 52 to form a P2 laser groove 82 .

[0177] Step S307, fill the P2 laser groove 82 with a second filling material, such as Figure 8 shown.

[0178] Step S308, forming a P3 laser groove 83, the P3 laser groove 83 penetrates the etching layer 40, the second window layer 51, and the second absorption layer 52, and obtains a first component structure, such as Figure 8 shown.

[0179] Step S309: performing a hot bending process and a Cl treatment process on the first component structure.

[0180] Step S310 , performing surface acid treatment on the first component structure.

[0181] Step S311, a back contact layer 60 is formed on the surface of the second absorption layer 52 facing away from the second window layer 51 by a Cu treatment process; the back contact layer 60 also covers the inner wall of the P3 laser groove 83, such as Figure 9 As shown, the material of the back contact layer 60 is metal.

[0182] Step S312, forming a back electrode layer 70 on the surface of the back contact layer 60 facing away from the second absorption layer 52; the back electrode layer 70 is also filled with the P3 laser groove 83, such as Figure 9 As shown, the material of the back electrode layer 70 is metal.

[0183] Step S313, placing the second component structure in a local stripping solution and performing ultrasonic treatment, decomposing the interface layer between the second window layer 51 corresponding to the position of the P1 laser groove 81 and the first filling material, removing the second window layer 51, the second absorption layer 52, the back contact layer 60 and the back electrode layer 70 corresponding to the position of the P1 laser groove 81, and forming a groove 90; the groove 90 separates the back contact layer 60 and the back electrode layer 70 on both sides of the P1 laser groove 81, as shown in FIG. Figure 10 shown.

[0184] In order to verify the effect of the method for preparing the curved cadmium telluride thin film photovoltaic module provided by the present invention, this application provides Example 1 and Comparative Example 1 to prepare different curved cadmium telluride thin film photovoltaic modules. Example 1 is as follows Figure 6 The preparation method shown is used, wherein the etching layer is a first window layer / first absorption layer stack; the first window layer is located on the side of the high resistance layer facing away from the transparent conductive layer; the first absorption layer is located on the side of the first window layer facing away from the high resistance layer, Figure 11 Schematic diagram of the structure of the curved cadmium telluride thin film photovoltaic module obtained by Example 1. Comparative Example 1 is a conventional photovoltaic module preparation method.

[0185] The preparation method provided by Comparative Example 1 comprises: providing a 2.5 mm to 3.2 mm ultra-white soda-lime glass substrate; depositing a Sn02:F (FTO) transparent conductive layer with a thickness of 300 nm to 600 nm on the glass substrate; depositing a Sn02 high resistance layer with a thickness of 20 nm to 60 nm on the FTO transparent conductive layer; depositing a CdSe window layer with a thickness of 50 nm to 200 nm on the Sn02 high resistance layer; depositing a CdTe absorption layer with a thickness of 2 μm to 3 μm on the CdSe window layer; performing a first laser treatment using a 1064 nm wavelength laser to etch the transparent conductive layer / high resistance layer / window layer / absorption layer; performing P1 laser groove insulation filling using a nanometer silicon solution; performing a second laser treatment using a 532 nm wavelength laser to etch the window layer / absorption layer; performing a 600 °C and 3 min heat bending treatment to form a hyperbolic shape, the substrate is only a simple regular shape, and the maximum arch height is < 15 mm; performing a Cl treatment at 400 °C to 450 °C for 5 min to 60 min; performing cadmium telluride surface treatment using a 0.5% to 1% dilute hydrochloric acid solution; depositing a ZnTe back contact layer with a thickness of 5 nm to 30 nm and a Cu doping content of 0.1% to 5% on the absorption layer; depositing a back electrode layer with a thickness of 100 nm on the back contact layer; performing a third laser treatment using a 532 nm wavelength laser to etch the window layer / absorption layer / back contact layer / metal back electrode layer; and completing the preparation of the heat-bent curved surface assembly. The heat-bent hyperbolic cadmium telluride assembly product prepared by the comparative example has a regular and single shape, and the maximum arch height of the bending must be less than < 15 mm, which is mainly limited by the process level of the existing market curved surface laser etching equipment.

[0186] The preparation method provided in Example 1 comprises: providing a super-white sodium-calcium glass substrate with a thickness of 2.5 mm to 3.2 mm; depositing a SnO2:F (FTO) transparent conductive layer with a thickness of 300 nm to 600 nm on the glass substrate; depositing a SnO2 high-resistance layer with a thickness of 20 nm to 60 nm on the FTO transparent conductive layer; depositing a CdSe first window layer with a thickness of 50 nm to 200 nm on the SnO2 high-resistance layer; depositing a CdTe first absorption layer with a thickness of 0.3 μm to 2 μm on the CdSe window layer; performing a first laser treatment by using a first laser (laser with a wavelength of 532 nm) to etch the first window layer / first absorption layer and form a P1 laser groove; filling the P1 laser groove with a first filling material, and the first filling material is SiO2 or a SiO2 / Ni composite layer; depositing a CdSe second window layer with a thickness of 50 nm to 400 nm and a CdTe second absorption layer with a thickness of 1 μm to 4 μm; performing a second laser treatment by using a second laser (laser with a wavelength of 1064 nm) to etch the transparent conductive layer / first window layer / first absorption layer / second window layer / second absorption layer and form a P2 laser groove; performing SiO2 filling on the P2 laser groove; performing a third laser treatment by using a third laser (laser with a wavelength of 532 nm) to etch the first window layer / first absorption layer / second window layer / second absorption layer and form a P3 laser groove; performing a hot bending treatment at 600 ℃ for 3 min to form a double-curved shape; performing a Cl treatment at 400 ℃ to 450 ℃ for 5 min to 60 min; performing cadmium telluride surface treatment by using a 0.5% to 1% dilute hydrochloric acid solution; depositing a ZnTe back contact layer with a thickness of 10 nm to 100 nm containing Cu; depositing a MoAl back electrode layer with a thickness of 60 nm to 200 nm; performing ultrasonic treatment in the hydrochloric acid solution for 1 min to 10 min to make all film layers above the transparent conductive layer at the position of the P1 laser groove (the second window layer / second absorption layer / back contact layer / back electrode layer) fall off to form a groove, and the groove can make the metal film layers (back contact layer / back electrode layer) on both sides of the P1 laser groove disconnected and insulated. Compared with Comparative Example 1, the preparation method provided in Example 1 completes all three laser integration processes before high-temperature hot bending forming, thereby avoiding the requirement and limitation of a curved laser processing device and process, and enabling the preparation of a curved photovoltaic module with an arbitrary shape.

[0187] The embodiment also provides a curved cadmium telluride thin-film photovoltaic module, as shown in Figure 6 The curved cadmium telluride thin-film photovoltaic module comprises:

[0188] a glass substrate 10, a transparent conductive layer 20, a high-resistance layer 30, an etching layer 40, a second absorption layer 52, a back contact layer 60, and a back electrode layer 70 which are sequentially stacked;

[0189] A P1 laser groove 81 , wherein the P1 laser groove 81 penetrates the etching layer 40 , and the filling material of the P1 laser groove 81 is a first filling material;

[0190] The groove 90 penetrates the second absorption layer 52 , the back contact layer 60 and the back electrode layer 70 corresponding to the position of the P1 laser groove 81 and exposes the surface of the P1 laser groove 81 ;

[0191] A P2 laser groove 82, the P2 laser groove 82 penetrates the transparent conductive layer 20, the high-resistance layer 30, the etching layer 40, and the second absorption layer 52, and the filling material of the P2 laser groove 82 is the second filling material;

[0192] P3 laser groove 83, P3 laser groove 83 penetrates the etching layer 40 and the second absorption layer 52;

[0193] The back contact layer 60 and the back electrode layer 70 also fill the P3 laser groove 83 and cover the surfaces of the P2 laser groove 82 and the P3 laser groove 83 .

[0194] The curved cadmium telluride thin-film photovoltaic module provided in this embodiment can achieve separation and insulation of the back contact layer and the back electrode layer on both sides of the P1 laser groove by providing a groove that passes through the second absorption layer, back contact layer and back electrode layer corresponding to the position of the P1 laser groove and exposes the surface of the P1 laser groove; at the same time, the curved cadmium telluride thin-film photovoltaic module can have any curved shape.

[0195] In some optional embodiments, the first filling material includes one or two layers of Al2O3, SiO2, Si3N4, ZrO2, NaCl, MgTe, Ni, Mo, and Cr;

[0196] The second filling material is an insulating material;

[0197] The material of the second absorption layer 52 is CdTe, CdSTe, CdSeTe, CdMgTe, CdZnTe, CdSSeTe or CdZnSSeTe.

[0198] In some optional embodiments, the curved cadmium telluride thin-film photovoltaic module further comprises:

[0199] The second window layer 51 is located on the surface of the etching layer 40 facing away from the high-resistance layer 30; the second window layer 51 is located between the etching layer 40 and the second absorption layer 52; the second window layer 51 covers the surface of the P1 laser groove 81;

[0200] The P3 laser groove 83 penetrates the etching layer 40, the second window layer 51 and the second absorption layer 52;

[0201] The groove 90 passes through the second window layer 51 , the second absorption layer 52 , the back contact layer 60 and the back electrode layer 70 corresponding to the position of the P1 laser groove 81 ;

[0202] The material of the second window layer 51 is CdS, CdSe, CdS:O, CdSe:O, CdSSe or CdSSeO;

[0203] The thickness of the second window layer 51 is 50 nm to 400 nm;

[0204] The thickness of the second absorption layer 52 is 1 μm to 4 μm.

[0205] In some optional embodiments, the etching layer 40 is a first window layer 41, a first absorption layer 42, or a first window layer 41 / first absorption layer 42 stack;

[0206] The material of the first window layer 41 is CdS, CdSe, CdS:O, CdSe:O, CdSSe or CdSSeO;

[0207] The material of the first absorption layer 42 is CdTe, CdSTe, CdSeTe, CdMgTe, CdZnTe, CdSSeTe or CdZnSSeTe.

[0208] In a specific implementation, the material of the first window layer 41 can be the same as or different from the material of the second window layer 51; the material of the first absorption layer 42 can be the same as or different from the material of the second absorption layer 52. In one example, the material of the first absorption layer 42 is different from the material of the second absorption layer 52, and the Cd and Te compositions in the first absorption layer 42 and the second absorption layer 52 vary in a gradient.

[0209] In the curved cadmium telluride thin-film photovoltaic module provided in this embodiment, the etched layer is a first absorption layer or a first window layer / first absorption layer stack; a first absorption layer and a second absorption layer with a composition gradient can be set in the curved cadmium telluride thin-film photovoltaic module to improve the light absorption effect of the photovoltaic module and thereby improve the photoelectric conversion efficiency of the photovoltaic module.

[0210] In some optional embodiments, the etching layer 40 is a stack of a first window layer 41 and a first absorption layer 42; the first window layer 41 is located on the surface of the high resistance layer 30 facing away from the transparent conductive layer 20; the first absorption layer 42 is located on the surface of the first window layer 41 facing away from the high resistance layer 30;

[0211] The thickness of the first window layer 41 is 50 nm to 200 nm;

[0212] The thickness of the first absorption layer 42 is 0.3 μm to 3 μm.

[0213] In some optional embodiments, the material of the etching layer 40 is a metal thin film material, and the metal thin film material is Al, Cr, ZnO or MgTe.

[0214] In some optional embodiments, the material of the transparent conductive layer 20 is SnO2:F (FTO); the thickness of the transparent conductive layer is 300nm to 600nm;

[0215] The material of the high resistance layer is SnO2; the thickness of the high resistance layer is 20nm to 60nm;

[0216] The material of the first window layer 41 is CdSe; the material of the first absorption layer 42 is CdTe;

[0217] The material of the second window layer 51 is CdSe; the material of the second absorption layer 52 is CdTe;

[0218] The material of the back contact layer is ZnTe containing Cu; the thickness of the back contact layer is 10nm to 100nm;

[0219] The material of the back electrode layer is MoAl; the thickness of the back electrode layer is 60 nm to 200 nm.

[0220] In the description of this specification, the reference terms "this embodiment", "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in an appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples, unless otherwise clearly defined. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, "multiple" means at least two, such as two, three, etc., unless otherwise clearly defined.

[0221] While the above description does not provide detailed technical details regarding patterning and etching of each layer, those skilled in the art will appreciate that various technical means can be employed to form layers, regions, and the like in desired shapes. Furthermore, those skilled in the art may devise methods that differ from those described above to form the same structure. Furthermore, while each embodiment has been described separately, this does not mean that the measures in each embodiment cannot be advantageously combined.

[0222] The above are only preferred embodiments 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 that various obvious changes, readjustments, combinations, and substitutions can be made by those skilled in the art 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: Providing a glass substrate, and sequentially depositing a transparent conductive layer, a high-resistance layer, and an etching layer on the glass substrate; forming a P1 laser groove, wherein the P1 laser groove penetrates the etching layer, and a filling material of the P1 laser groove is a first filling material; forming a second absorption layer on a side of the etching layer facing away from the high-resistance layer; the second absorption layer covers the surface of the P1 laser groove; forming a P2 laser groove, wherein the P2 laser groove penetrates the transparent conductive layer, the high-resistance layer, the etching layer, and the second absorption layer, and the filling material of the P2 laser groove is the second filling material; forming a P3 laser groove, wherein the P3 laser groove penetrates the etching layer and the second absorption layer; and obtaining a first component structure; performing a hot bending process and a Cl treatment process on the first component structure; forming a back contact layer and a back electrode layer in sequence on a surface of the second absorption layer facing away from the etching layer to obtain a second component structure, wherein the back contact layer and the back electrode layer also fill the P3 laser groove; The second component structure is subjected to a local stripping process to remove the second absorption layer, the back contact layer and the back electrode layer corresponding to the position of the P1 laser groove to form a groove.

2. The method for preparing a curved cadmium telluride thin-film photovoltaic module according to claim 1, wherein: The step of forming the P1 laser groove includes: Using a first laser to etch the etching layer to form a P1 laser groove; Filling the P1 laser groove with a first filling material; The step of forming the P2 laser groove includes: Using a second laser to etch the transparent conductive layer, the high-resistance layer, the etching layer, and the second absorption layer to form a P2 laser groove; The P2 laser trench is filled with a second filling material.

3. The method for preparing a curved cadmium telluride thin film photovoltaic module according to claim 2, wherein: In the step of forming the second absorption layer, the second absorption layer contacts the first filling material in the P1 laser groove, and the stress between the second absorption layer and the first filling material is greater than 0.5 GPa; an interface layer is formed between the second absorption layer and the first filling material; In the local stripping process, the interface layer between the second absorption layer and the first filling material corresponding to the P1 laser groove position is decomposed, and the second absorption layer, back contact layer and back electrode layer corresponding to the P1 laser groove position are removed to form a groove.

4. The method for preparing a curved cadmium telluride thin film photovoltaic module according to claim 2, wherein: The step of forming the second absorption layer comprises: A second window layer is formed on a surface of the etching layer facing away from the high-resistance layer; the second window layer covers the surface of the P1 laser groove; forming a second absorption layer on a surface of the second window layer facing away from the etching layer; The step of forming the groove comprises: Performing a local stripping process on the second component structure to remove the second window layer, the second absorption layer, the back contact layer and the back electrode layer corresponding to the position of the P1 laser groove to form a groove; In the step of forming the second window layer, the second window layer contacts the first filling material in the P1 laser groove, and the stress between the second window layer and the first filling material is greater than 0.5 GPa; an interface layer is formed between the second window layer and the first filling material; In the local film removal process, the interface layer between the second window layer corresponding to the P1 laser groove position and the first filling material is decomposed, and the second window layer, second absorption layer, back contact layer and back electrode layer corresponding to the P1 laser groove position are removed to form a groove.

5. The method for preparing a curved cadmium telluride thin-film photovoltaic module according to claim 4, wherein: The first filling material includes one or two layers of Al2O3, SiO2, Si3N4, ZrO2, NaCl, MgTe, Ni, Mo, and Cr; The second filling material is an insulating material; The material of the second window layer is CdS, CdSe, CdS:O, CdSe:O, CdSSe or CdSSeO; The material of the second absorption layer is CdTe, CdSTe, CdSeTe, CdMgTe, CdZnTe, CdSSeTe or CdZnSSeTe.

6. The method for preparing a curved cadmium telluride thin-film photovoltaic module according to claim 1, wherein: The local film removal process includes: Placing the second component structure in a local stripping solution and performing ultrasonic treatment to remove the second absorption layer, the back contact layer, and the back electrode layer corresponding to the position of the P1 laser groove to form a groove; the groove separates the back contact layer and the back electrode layer on both sides of the P1 laser groove; The local desmear solution includes an acid solution or an alkaline solution; The temperature of the local membrane removal solution is 30° C. to 100° C.; the time of the ultrasonic treatment is 1 min to 10 min.

7. The method for preparing a curved cadmium telluride thin-film photovoltaic module according to claim 1, wherein: The material of the back contact layer is metal; the material of the back electrode layer is metal; The step of forming the back contact layer and the back electrode layer comprises: performing surface acid treatment on the first component structure; A back contact layer is formed on the surface of the second absorption layer facing away from the etching layer by a Cu treatment process; the back contact layer also covers the inner wall of the P3 laser groove; A back electrode layer is formed on the surface of the back contact layer facing away from the second absorption layer; the back electrode layer also fills the P3 laser groove.

8. A curved cadmium telluride thin-film photovoltaic module, characterized in that: include: A glass substrate, a transparent conductive layer, a high-resistance layer, an etching layer, a second absorption layer, a back contact layer and a back electrode layer stacked in sequence; A P1 laser groove, wherein the P1 laser groove penetrates the etching layer, and a filling material of the P1 laser groove is a first filling material; A groove, which passes through the second absorption layer, the back contact layer and the back electrode layer corresponding to the position of the P1 laser groove and exposes the surface of the P1 laser groove; A P2 laser groove, wherein the P2 laser groove penetrates the transparent conductive layer, the high-resistance layer, the etching layer, and the second absorption layer, and the filling material of the P2 laser groove is the second filling material; A P3 laser groove, wherein the P3 laser groove passes through the etching layer and the second absorption layer; The back contact layer and the back electrode layer also fill the P3 laser groove and cover the surface of the P2 laser groove and the surface of the P3 laser groove.

9. The curved cadmium telluride thin-film photovoltaic module according to claim 8, characterized in that: The first filling material includes one or two layers of Al2O3, SiO2, Si3N4, ZrO2, NaCl, MgTe, Ni, Mo, and Cr; The second filling material is an insulating material; The material of the second absorption layer is CdTe, CdSTe, CdSeTe, CdMgTe, CdZnTe, CdSSeTe or CdZnSSeTe.

10. The curved cadmium telluride thin-film photovoltaic module according to claim 9, characterized in that: The curved cadmium telluride thin-film photovoltaic module further includes: A second window layer is located on a surface of the etching layer facing away from the high-resistance layer; the second window layer is located between the etching layer and the second absorption layer; the second window layer covers the surface of the P1 laser slot; The P3 laser groove passes through the etching layer, the second window layer and the second absorption layer; The groove passes through the second window layer, the second absorption layer, the back contact layer and the back electrode layer corresponding to the position of the P1 laser groove; The material of the second window layer is CdS, CdSe, CdS:O, CdSe:O, CdSSe or CdSSeO; The thickness of the second window layer is 50nm to 400nm; The thickness of the second absorption layer is 1 μm to 4 μm.

11. The curved cadmium telluride thin-film photovoltaic module according to claim 8, characterized in that: The material of the etching layer is a metal thin film material, and the metal thin film material is Al, Cr, ZnO or MgTe; or: The etching layer is a first window layer, a first absorption layer, or a first window layer / first absorption layer stack; The material of the first window layer is CdS, CdSe, CdS:O, CdSe:O, CdSSe or CdSSeO; The material of the first absorption layer is CdTe, CdSTe, CdSeTe, CdMgTe, CdZnTe, CdSSeTe or CdZnSSeTe; The thickness of the first window layer is 50nm to 200nm; The thickness of the first absorption layer is 0.3 μm to 3 μm.

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