Perovskite battery structure and preparation method thereof
By employing low-temperature plasma-enhanced chemical vapor deposition and etching processes to form a fully encapsulated structure in perovskite solar cells, the sensitivity of perovskite cells to humidity, high temperature, and light has been solved, resulting in perovskite solar cells with high stability and high-efficiency light capture.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HAC GENERAL SEMITECH CO LTD
- Filing Date
- 2026-01-29
- Publication Date
- 2026-04-21
AI Technical Summary
Perovskite solar cells are sensitive to humidity, high temperature and light, resulting in poor stability and affecting their commercial application.
A silicon-containing protective film is deposited on a transparent substrate using low-temperature plasma-enhanced chemical vapor deposition to form the first and second protective layers. Multiple independent TCO substrates and channels are then constructed through etching processes to achieve full encapsulation. Combined with low-temperature deposition of the back electrode and protective layer, a high-precision electrical interconnect and isolation structure is formed.
It significantly improves the environmental stability and performance of perovskite solar cells, achieves seamless encapsulation of the cells, enhances mechanical reliability and light capture efficiency, and solves the problem of poor stability of perovskite solar cells.
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Figure CN121908734A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of solar cell technology, specifically to a perovskite cell structure and its preparation method. Background Technology
[0002] Perovskite solar cells (PSCs) are a new type of compound thin-film solar cell that utilizes perovskite materials as the light-absorbing layer. Due to their low manufacturing cost, high photoelectric conversion efficiency, flexibility, lightweight nature, tunable perovskite materials, and high low-light performance, they are considered a promising next-generation solar cell for the photovoltaic industry. However, perovskite materials (such as CH3NH3PbI3) are highly sensitive to the environment and are easily decomposed by humidity, high temperature (>85℃), and light-induced degradation, leading to performance degradation. Unencapsulated devices fail within hours in environments with humidity >50%, and this poor stability is the biggest obstacle to the commercial application of perovskite solar cells.
[0003] Current research on the stability of perovskite solar cells mainly focuses on modifying the perovskite material itself through structural design, element substitution, and doping, as well as using post-modification materials to protect the perovskite layer and improve its stability. While modifying the perovskite material itself, it's impossible to completely prevent degradation reactions triggered by ultraviolet to blue-green light (wavelengths 300-500 nm) irradiation on the perovskite solar cell. Ultraviolet light (<400 nm) is the most destructive, followed by visible light (500-600 nm), while longer wavelengths (>600 nm) have a weaker impact but may indirectly affect the perovskite solar cell through defects. Because perovskite materials are susceptible to humidity and high temperatures (>85℃), the method of protecting the perovskite layer with post-modification materials places stringent requirements on raw materials and temperatures, such as requiring processing under ultra-low humidity and low temperature conditions, thus further limiting the large-scale industrial application of perovskite solar cells. Summary of the Invention
[0004] In view of the shortcomings of the prior art, the purpose of this invention is to provide a perovskite battery structure and its preparation method, aiming to solve the above-mentioned problems described in the prior art.
[0005] A first aspect of the present invention is to provide a method for preparing a perovskite solar cell structure, the method comprising: A transparent substrate is provided, and a silicon-containing protective film is deposited on one side surface of the transparent substrate to form a first protective layer; A conductive film layer is deposited on the first protective layer, and the conductive film layer is etched to form a first etching channel, thereby obtaining multiple independent TCO substrates. A hole transport layer, a perovskite layer, and an electron transport layer are sequentially deposited on the conductive film layer. The hole transport layer, perovskite layer and electron transport layer are etched to form a second channel that exposes the surface of the conductive film layer; A back electrode is deposited on the electron transport layer, such that the back electrode contacts the conductive film layer within the second channel; The back electrode, the electron transport layer, the perovskite layer and the hole transport layer are etched to form a third channel that exposes the surface of the conductive film layer, thereby obtaining multiple sub-cells; A silicon-containing protective film is deposited on the back electrode to form a second protective layer, and the second protective layer is made to contact the conductive film layer in the third channel.
[0006] According to one aspect of the above technical solution, the silicon-containing protective film is deposited to form the first protective layer and the second protective layer by plasma-enhanced chemical vapor deposition, and the deposition temperature is <80°C. The silicon-containing protective film is made of a single layer of silicon nitride, or a laminated film of silicon nitride / silicon oxide, silicon nitride / silicon oxynitride, or silicon nitride / silicon oxide / silicon nitride.
[0007] According to one aspect of the above technical solution, the etching depth of the first etching channel penetrates the conductive film layer and extends at least partially into the first protective layer, so that the conductive film layer is physically separated into a plurality of mutually insulating TCO substrates.
[0008] According to one aspect of the above technical solution, the step of forming the second channel includes: The electron transport layer, the perovskite layer, and the hole transport layer are sequentially etched using laser or mask etching processes to expose the surface of the underlying conductive film layer, forming a contact window for connecting the back electrode.
[0009] According to one aspect of the above technical solution, the step of forming the third channel is synchronous etching; The material of the back electrode, the electron transport layer, the perovskite layer and the hole transport layer in a predetermined area is removed simultaneously by a single etching process to expose the surface of the conductive film layer.
[0010] According to one aspect of the above technical solution, the third channel is positioned at the orthographic projection location on the surface of the conductive film layer to form an isolation region for isolating adjacent sub-cells.
[0011] According to one aspect of the above technical solution, when depositing the second protective layer, the silicon-containing protective film simultaneously covers the upper surface of the back electrode and fills the third channel, and directly contacts the surface of the conductive film layer at the bottom of the third channel, thereby realizing the integration of side encapsulation and top encapsulation at the edge of the sub-cell.
[0012] According to one aspect of the above technical solution, the process for depositing the back electrode is vacuum evaporation or magnetron sputtering; The back electrode is a metal electrode, and its material is one or more of silver, aluminum, copper or gold.
[0013] A second aspect of the present invention is to provide a perovskite solar cell structure, which is prepared by the preparation method described in the above technical solution.
[0014] According to one aspect of the above technical solution, from bottom to top, it includes: A transparent substrate, a first protective layer, a conductive film layer patterned and separated by a first channel, a hole transport layer, a perovskite layer, an electron transport layer, a back electrode, and a continuously covered second protective layer. The second protective layer fills the third channel and contacts the conductive film layer to form an integrated encapsulation structure for the perovskite solar cell.
[0015] Compared with existing technologies, the perovskite solar cell structure and its preparation method shown in this invention have the following advantages: The fabrication method described in this invention significantly improves the performance and reliability of perovskite solar cells through innovative full-encapsulation and progressive patterning processes. The initial and final steps employ low-temperature PECVD technology to deposit silicon-containing protective films to form the first and second protective layers, respectively. The second protective layer completely fills the third channel of the isolation sub-cell and connects with the underlying first protective layer, achieving a seamless integrated seal for the top, sides, and bottom of the cell, fundamentally solving the problem of poor environmental stability in perovskite devices. Furthermore, through multiple precise etching processes, a low-loss, high-precision electrical interconnect and isolation structure is synergistically constructed. In addition, the protective layer also possesses optical modulation and interface optimization functions, ensuring extreme water and oxygen barrier while simultaneously achieving efficient light capture and carrier transport. In summary, this invention achieves highly stable and high-precision integrated molding of perovskite solar cells through full-encapsulation and low-temperature processes. Attached Figure Description
[0016] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 A schematic flowchart illustrating the fabrication method of the perovskite battery structure provided in this embodiment of the invention; Figure 2 This is a schematic diagram of the perovskite solar cell structure provided in an embodiment of the present invention; Component symbol explanation in the attached diagram: Transparent substrate 10, first protective layer 20, conductive film layer 30, hole transport layer 40, perovskite layer 50, electron transport layer 60, back electrode 70, second protective layer 80, first channel 101, second channel 102, and third channel 103. Detailed Implementation
[0017] To make the objectives, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Several embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of the present invention will be more thorough and complete.
[0018] It should be noted that when a component is said to be "fixed to" another component, it can be directly on the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.
[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0020] Example 1 Please see Figures 1-2 The first embodiment of the present invention provides a method for preparing a perovskite solar cell structure, the method comprising steps S10-S70: Step S10: A transparent substrate is provided, and a silicon-containing protective film is deposited on one side surface of the transparent substrate to form a first protective layer.
[0021] In this embodiment, the material of the silicon-containing protective film is a single-layer film of silicon nitride, or a stacked film of silicon nitride / silicon oxide, silicon nitride / silicon oxynitride, or silicon nitride / silicon oxide / silicon nitride.
[0022] The first protective layer 20, formed by depositing the silicon-containing protective film, is formed by plasma-enhanced chemical vapor deposition, and the deposition temperature is <80°C.
[0023] Specifically, in this embodiment, silicon nitride is chosen for its high density, excellent water and oxygen barrier properties, good chemical stability, and high mechanical hardness, making it an ideal encapsulation and protection material. Its single-layer film structure is simple to manufacture and effectively blocks the erosion of the perovskite active layer by the external environment. Furthermore, using a multilayer structure, such as silicon nitride / silicon oxide, silicon nitride / silicon oxynitride, or silicon nitride / silicon oxide / silicon nitride, can further optimize performance. The interfaces between different materials can suppress the propagation of pinhole defects, forming a more complete barrier network; by adjusting the stress matching of each layer, the risk of film cracking or peeling can be reduced; and multilayer film systems can achieve better optical transmittance and refractive index matching, thereby improving light capture efficiency.
[0024] Low-temperature plasma-enhanced chemical vapor deposition (PECVD) offers several advantages. The deposition temperature is strictly controlled below 80°C, preventing thermal stress damage to the transparent substrate 10 and thermal degradation of the underlying perovskite material. PECVD activates the reactive gas through plasma, enabling high-density, highly uniform thin film deposition at low temperatures, with strong adhesion between the film and the substrate. The low-temperature conditions also make this process suitable for flexible devices and temperature-sensitive all-solution processing, facilitating integration into existing perovskite solar cell production lines.
[0025] More specifically, the first protective layer 20 plays a dual role in the battery structure. On the one hand, it provides interface protection, directly deposited on the surface of the transparent substrate 10, which can enhance the substrate's scratch resistance and serve as a buffer layer for the subsequent deposition of the transparent conductive layer, improving the flatness and crystal quality of the conductive layer. On the other hand, as a primary barrier, it forms the first anti-permeation barrier before the complete battery encapsulation, providing pretreatment protection for the subsequent perovskite active layer and other functional layers, thereby improving the overall environmental stability of the device.
[0026] Step S20: Deposit a conductive film layer on the first protective layer, etch the conductive film layer to form a first etching channel, and obtain multiple independent TCO substrates.
[0027] In this embodiment, the etching depth of the first etching channel penetrates the conductive film layer 30 and extends at least partially into the first protective layer 20, so that the conductive film layer 30 is physically separated into a plurality of mutually insulating TCO substrates.
[0028] Specifically, in this embodiment, by precisely controlling the etching depth, the aim is to construct mutually independent and insulated transparent electrode units for the subsequent battery structure, which is the core process for defining the effective area of the device and achieving electrical isolation.
[0029] From the fundamental purpose of electrical isolation, it is crucial to control the depth of the first etched trench to extend at least partially into the first protective layer 20. If the etching only stops within the conductive film layer 30 without penetrating the underlying first protective layer 20, extremely thin conductive films or conductive particles may remain at the bottom of the trench, leading to leakage or even short circuits between units. Etching deep into the first protective layer 20 can completely remove all conductive material in that area, ensuring that adjacent TCO substrates are completely physically isolated by a high-resistivity silicon-containing protective material, thereby achieving reliable electrical insulation.
[0030] The etching process (such as wet etching or plasma dry etching) needs to be able to efficiently remove the upper conductive film (such as ITO / FTO), while the etching rate of the underlying silicon nitride or silicon oxide protective layer is relatively low and controllable. This etching selectivity ensures the formation of clear, vertical channel sidewalls and allows for precise control of the depth of penetration into the protective layer, avoiding severe damage or even penetration of the entire first protective layer 20 due to over-etching, thereby ensuring that its protective function for the substrate is not compromised.
[0031] From the perspective of physical structural support and compatibility with subsequent processes, the structure of the channel extending into the first protective layer 20 provides a more stable physical anchoring foundation for each independent TCO substrate, enhances the adhesion between the electrode and the substrate, and helps improve the mechanical reliability of the device. At the same time, the bottom of the formed channel is made of the first protective layer 20 material, which provides a clean, flat and insulating interface for functional layers (such as electron transport layer 60) that may be directly fabricated on it in subsequent steps, avoiding electrical crosstalk between battery cells on different TCO substrates at the edges.
[0032] Step S30: A hole transport layer, a perovskite layer, and an electron transport layer are sequentially deposited on the conductive film layer.
[0033] Specifically, in this embodiment, step S30 is a key process for constructing the core photoelectric conversion functional junction of the perovskite solar cell. On a patterned and mutually insulated TCO substrate, a hole transport layer 40, a perovskite light-absorbing layer, and an electron transport layer 60 are deposited sequentially to form a planar heterojunction or mesoscopic photoelectric conversion unit, laying the foundation for converting light energy into electrical energy.
[0034] First, a hole transport layer 40 is deposited on a TCO substrate. This layer is typically composed of organic small molecule materials (such as Spiro-OMeTAD) or inorganic materials (such as NiO). x It consists of components such as the perovskite layer 50. It reduces carrier recombination by selectively collecting and transporting photogenerated holes generated by the perovskite layer 50 and blocking the flow of electrons to the TCO electrode. During the deposition of this layer, it is necessary to ensure that the film is uniform, dense, and completely covers the TCO surface to form a good ohmic contact.
[0035] Secondly, a perovskite layer 50, also known as the perovskite photoactive layer, is deposited. The perovskite material (usually an organic-inorganic hybrid perovskite, such as CH3NH3PbI3) is the core of the device, responsible for absorbing sunlight and generating photogenerated electron-hole pairs. Deposition can be achieved using processes such as solution spin-coating, two-step solution deposition, and vapor-assisted deposition. By controlling the film coverage, crystallinity, grain size, and defect state density, a high-quality film with high absorption coefficient, long carrier diffusion length, and low recombination loss can be obtained. Furthermore, the deposition process must be carried out in an inert atmosphere or a controlled environment to prevent material decomposition.
[0036] Finally, an electron transport layer 60 is deposited on top of the perovskite layer 50. This layer is typically composed of a wide-bandgap n-type semiconductor material, such as titanium dioxide or tin oxide. Its main function is to efficiently extract and transport electrons from the perovskite layer 50, while blocking the transport of holes to the counter electrode. When depositing this layer, in addition to considering the electron mobility and energy level matching of the material itself, special attention must be paid to protecting the underlying perovskite film to avoid corrosion or damage to the sensitive perovskite material caused by solvents or high-energy particles during the deposition process.
[0037] Step S40: Etch the hole transport layer, perovskite layer and electron transport layer to form a second channel that exposes the surface of the conductive film layer.
[0038] In this embodiment, the step of forming the second channel 102 includes: The electron transport layer 60, the perovskite layer 50 and the hole transport layer 40 are sequentially etched using laser or mask etching processes to expose the surface of the underlying conductive film layer 30, forming a contact window for connecting the back electrode 70.
[0039] Specifically, in this embodiment, selectively removing functional layer material in certain areas establishes a physical channel for connecting the back electrode 70 to the underlying transparent conductive electrode, which is a necessary prerequisite for effectively collecting the internal current of the battery and interconnecting and integrating battery cells.
[0040] In the planar positive structure, the hole transport layer 40, perovskite layer 50, and electron transport layer 60 are stacked sequentially, completely covering the underlying TCO substrate. Without this step, the upper back electrode 70 would contact the electron transport layer 60 and would not be able to form an electrical connection with the lower TCO positive electrode. By etching to form the second channel 102, the upper three semiconductor thin films are precisely removed in a designated area, thereby opening a contact window and exposing the underlying TCO surface. This allows the subsequently deposited back electrode 70 metal to directly form an ohmic contact with the TCO through this window, constructing a complete current extraction path.
[0041] The etching process for forming the second channel 102 can be either laser etching or mask etching. Laser etching offers advantages such as non-contact operation, high precision, and flexible patterning. However, its heat-affected zone (HAZ) must be strictly controlled to prevent thermal damage to the perovskite layer 50 or degradation of the TCO performance. Mask etching (such as wet or dry etching after photolithography) is suitable for large-area, high-consistency patterning. The key is to control the selective etching of each layer, ensuring that the electron transport layer 60, perovskite layer 50, and hole transport layer 40 are etched sequentially, while minimizing damage to the exposed TCO surface and protecting the integrity of the film in areas that do not require etching.
[0042] Furthermore, the second channel 102 and the first etched channel are designed in a coordinated manner in terms of function and location. The first channel 101 is used to isolate adjacent battery sub-cells, while the second channel 102 is located outside the effective area of a single sub-cell (typically near the edge of the sub-cell or a specific design area) to enable the connection between the TCO and the back electrode 70 within the same cell.
[0043] Step S50: Deposit a back electrode on the electron transport layer, so that the back electrode is in contact with the conductive film layer in the second channel.
[0044] In this embodiment, the back electrode 70 is typically made of a highly conductive, highly reflective, and work function-matched metallic material, such as silver, gold, aluminum, or a composite structure thereof. During the deposition process, physical vapor deposition techniques such as thermal evaporation, electron beam evaporation, or sputtering can be used to ensure that metal atoms or particles can be deposited into a film at a lower substrate temperature and controllable kinetic energy. This effectively avoids thermal or bombardment damage to the underlying sensitive perovskite layer 50 and organic transport layer caused by high-temperature or high-energy particles generated during the deposition process, thus ensuring the integrity of the underlying functional structure.
[0045] Specifically, during deposition, the metal material simultaneously covers the upper surface of the electron transport layer 60 and the sidewalls and bottom of the second channel 102. At the bottom of the channel, the metal directly contacts the exposed transparent conductive oxide, forming an ohmic contact between the metal and semiconductor (or metal and transparent conductive oxide), providing a low-resistance conductive path from the TCO positive electrode to the back electrode 70. To ensure contact quality, the etching of the second channel 102 must thoroughly remove all functional layer residues at the bottom of the channel, ensuring a clean TCO surface. Furthermore, the deposited metal must possess good step coverage to completely fill the bottom of the channel, avoiding problems such as excessive contact resistance or even open circuits due to incomplete coverage.
[0046] Furthermore, the back electrode 70, serving as the negative electrode of the device, forms contact with the electron transport layer 60, responsible for collecting and exporting electrons transported via the electron transport layer 60. Simultaneously, it achieves physical connection with the TCO substrate, serving as the positive electrode, through the second channel 102, thus forming a closed loop of TCO-perovskite-back electrode 70 within a single cell. Additionally, the highly reflective metal back electrode 70 can reflect transmitted light that is not completely absorbed by the perovskite layer 50 back for secondary absorption, thereby enhancing the device's light capture efficiency and increasing the short-circuit current.
[0047] Step S60: Etch the back electrode, the electron transport layer, the perovskite layer and the hole transport layer to form a third channel that exposes the surface of the conductive film layer, thereby obtaining multiple sub-cells.
[0048] In this embodiment, the step of forming the third channel 103 is synchronous etching; The material of the back electrode 70, the electron transport layer 60, the perovskite layer 50 and the hole transport layer 40 in a predetermined area is removed simultaneously by a single etching process to expose the surface of the conductive film layer 30.
[0049] Furthermore, the third channel 103 is positioned at the orthographic projection location on the surface of the conductive film layer 30 to form an isolation region for isolating adjacent sub-cells.
[0050] Specifically, in this embodiment, step S60 is the final key step in patterning to complete the monolithic integration of the perovskite solar cell and achieve electrical isolation of multiple independent sub-cell units. This step completely severs the entire functional layer stack, including the back electrode 70, at a predetermined location through a single etching process, thereby physically and electrically dividing the large-area continuous thin film into multiple independent cell units connected in series or parallel.
[0051] The synchronous etching process is the core of this step, requiring the sequential etching or simultaneous removal of the back electrode 70, electron transport layer 60, perovskite layer 50, and hole transport layer 40 in a single processing cycle. This necessitates that the etching process effectively removes various materials involved (metals, metal oxides, organic-inorganic hybrid perovskites, organic semiconductors, etc.) and exhibits good anisotropy to form trenches with steep sidewalls and clear boundaries. Simultaneously, it must ensure that the etching precisely stops on the surface of the underlying conductive film layer 30, avoiding excessive damage. Compared to multi-layer etching, synchronous etching greatly simplifies the process, reduces the number of alignment steps, and improves production efficiency and accuracy.
[0052] The third channel 103 works structurally in conjunction with the first and second channels 102 formed earlier to jointly define the unit structure and current path of the sub-cell. The first channel 101, during the initial fabrication stage, divided the bottom TCO conductive film layer 30 into mutually insulating blocks. The third channel 103, building upon this, further divides all upper functional layers from top to bottom. The orthographic projection of its channel onto the surface of the conductive film layer 30 must be precisely aligned with or have a specific positional relationship with the first etched channel. Optionally, the third channel 103 and the first channel 101 can be staggered or overlapped in projection, ensuring that the TCO positive electrode of one sub-cell is electrically connected to the back electrode 70 of the adjacent sub-cell through subsequent interconnection structures, ultimately connecting all sub-cells in series. Therefore, the third channel 103 essentially defines the boundary and effective area of each sub-cell.
[0053] Furthermore, the etching of the third channel 103 completely eliminates the possibility of bypass leakage or short circuits between adjacent sub-cells through the upper common functional layer, especially the continuous back electrode 70 and perovskite layer 50, ensuring the electrical independence of each sub-cell. The formed isolation region, i.e., the third channel 103, must have sufficient width to withstand the material filling in subsequent packaging processes and the possible degradation of insulation performance during long-term use. At the same time, precisely controlled etching avoids irreversible damage to the exposed TCO surface, preserving a good foundation for subsequent cleaning or interface treatment steps that may be required.
[0054] Step S70: A silicon-containing protective film is deposited on the back electrode to form a second protective layer, and the second protective layer is made to contact the conductive film layer in the third channel.
[0055] In this embodiment, when the second protective layer 80 is deposited, the silicon-containing protective film simultaneously covers the upper surface of the back electrode 70 and fills the third channel 103, and directly contacts the surface of the conductive film layer 30 at the bottom of the third channel 103, thereby realizing the integration of side encapsulation and top encapsulation at the edge of the sub-cell.
[0056] Specifically, this step continues to use a silicon-containing protective film as the encapsulation material, which corresponds to the first protective layer 20 formed in step S10. This ensures that the entire device has consistent and excellent barrier performance on the top and sides. In addition, the deposition process also adopts low-temperature plasma-enhanced chemical vapor deposition, which can avoid damage to the already prepared heat-sensitive perovskite layer 50, organic transport layer and metal back electrode 70 caused by high temperature, and ensure that the performance of the previous functional layers does not degrade after encapsulation.
[0057] The deposited second protective layer 80 completely fills the third channel 103 and directly contacts the exposed conductive film layer 30 at the bottom of the channel to achieve three key functions: First, the third channel 103 is a deep trench that runs through all functional layers and is the most vulnerable path for environmental water and oxygen to penetrate into the device. The filled protective film can wrap the sidewalls of the channel without dead angles and seal its bottom, completely blocking the penetration channel; Second, the second protective layer 80 and the first protective layer 20 are connected through the bottom of the channel, so that the protection on the device substrate side and the protection on the top are connected in the battery cell isolation area, forming a continuous protective shell from bottom to top; In addition, the solid protective material filled in the channel can also play a role in mechanical support and stress buffering, enhancing the overall mechanical strength of the multilayer thin film stacked structure.
[0058] Furthermore, the second protective layer 80 serves as the final encapsulation medium, directly protecting the topmost back electrode 70 and working in conjunction with the first protective layer 20 to form a dual defense against water and oxygen penetration from both sides of the device.
[0059] In this embodiment, the perovskite solar cell structure obtained by the preparation method shown includes, from bottom to top, the following: The transparent substrate 10, the first protective layer 20, the conductive film layer 30 patterned and separated by the first channel 101, the hole transport layer 40, the perovskite layer 50, the electron transport layer 60, the back electrode 70, and the continuously covered second protective layer 80. The second protective layer 80 fills the third channel 103 and contacts the conductive film layer 30 to form an integrated encapsulation structure for the perovskite solar cell.
[0060] In summary, compared with existing technologies, the fabrication method of the perovskite solar cell structure shown in this embodiment has the following advantages: The fabrication method described in this embodiment significantly improves the performance and reliability of perovskite solar cells through innovative full-encapsulation and progressive patterning processes. The initial and final steps employ low-temperature PECVD technology to deposit silicon-containing protective films to form the first and second protective layers, respectively. The second protective layer completely fills the third channel of the isolation sub-cell and connects with the underlying first protective layer, achieving a seamless integrated seal for the top, sides, and bottom of the cell, fundamentally solving the problem of poor environmental stability in perovskite devices. Furthermore, through multiple precise etching processes, a low-loss, high-precision electrical interconnect and isolation structure is synergistically constructed. In addition, the protective layer also possesses optical modulation and interface optimization functions, ensuring extreme water and oxygen barrier while simultaneously achieving efficient light capture and carrier transport. In summary, this embodiment achieves highly stable and high-precision integrated molding of perovskite solar cells through full-encapsulation and low-temperature processes.
[0061] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0062] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this patent should be determined by the appended claims.
Claims
1. A method for preparing a perovskite solar cell structure, characterized in that, The preparation method includes: A transparent substrate is provided, and a silicon-containing protective film is deposited on one side surface of the transparent substrate to form a first protective layer; A conductive film layer is deposited on the first protective layer, and the conductive film layer is etched to form a first etching channel, thereby obtaining multiple independent TCO substrates. A hole transport layer, a perovskite layer, and an electron transport layer are sequentially deposited on the conductive film layer. The hole transport layer, perovskite layer and electron transport layer are etched to form a second channel that exposes the surface of the conductive film layer; A back electrode is deposited on the electron transport layer, such that the back electrode contacts the conductive film layer within the second channel; The back electrode, the electron transport layer, the perovskite layer and the hole transport layer are etched to form a third channel that exposes the surface of the conductive film layer, thereby obtaining multiple sub-cells; A silicon-containing protective film is deposited on the back electrode to form a second protective layer, and the second protective layer is made to contact the conductive film layer in the third channel.
2. The method for preparing the perovskite solar cell structure according to claim 1, characterized in that, The silicon-containing protective film is deposited to form the first and second protective layers by plasma-enhanced chemical vapor deposition, and the deposition temperature is <80°C. The silicon-containing protective film is made of a single layer of silicon nitride, or a laminated film of silicon nitride / silicon oxide, silicon nitride / silicon oxynitride, or silicon nitride / silicon oxide / silicon nitride.
3. The method for preparing the perovskite solar cell structure according to claim 1, characterized in that, The etching depth of the first etching channel penetrates the conductive film layer and extends at least partially into the first protective layer, so that the conductive film layer is physically separated into a plurality of mutually insulating TCO substrates.
4. The method for preparing the perovskite solar cell structure according to claim 1, characterized in that, The steps for forming the second channel include: The electron transport layer, the perovskite layer, and the hole transport layer are sequentially etched using laser or mask etching processes to expose the surface of the underlying conductive film layer, forming a contact window for connecting the back electrode.
5. The method for preparing the perovskite solar cell structure according to claim 4, characterized in that, The step of forming the third channel is synchronous etching; The material of the back electrode, the electron transport layer, the perovskite layer and the hole transport layer in a predetermined area is removed simultaneously by a single etching process to expose the surface of the conductive film layer.
6. The method for preparing the perovskite solar cell structure according to claim 5, characterized in that, The third channel is positioned at the orthographic projection of the conductive film layer surface to form an isolation region for isolating adjacent sub-cells.
7. The method for preparing the perovskite solar cell structure according to claim 6, characterized in that, When the second protective layer is deposited, the silicon-containing protective film simultaneously covers the upper surface of the back electrode and fills the third channel, and directly contacts the surface of the conductive film layer at the bottom of the third channel, thereby realizing the integration of side encapsulation and top encapsulation at the edge of the sub-cell.
8. The method for preparing the perovskite solar cell structure according to claim 1, characterized in that, The process for depositing the back electrode is vacuum evaporation or magnetron sputtering; The back electrode is a metal electrode, and its material is one or more of silver, aluminum, copper or gold.
9. A perovskite solar cell structure, characterized in that, It is prepared by the preparation method according to any one of claims 1-8.
10. The perovskite solar cell structure according to claim 9, characterized in that, From bottom to top, they include: A transparent substrate, a first protective layer, a conductive film layer patterned and separated by a first channel, a hole transport layer, a perovskite layer, an electron transport layer, a back electrode, and a continuously covered second protective layer. The second protective layer fills the third channel and contacts the conductive film layer to form an integrated encapsulation structure for the perovskite solar cell.