Solar cell and preparation method thereof, photovoltaic module

Abstract

The present application relates to the field of solar cells, and in particular to a solar cell and a preparation method thereof, and a photovoltaic module. The solar cell comprises: a silicon substrate; a functional layer, which is arranged on the surface of the silicon substrate, the functional layer is a hydrogen-containing layer, and the functional layer is an anti-reflection layer or a doping layer; a hydrogen isolation layer, the thickness of the hydrogen isolation layer is 0.5 nm~5 nm; wherein the material of the hydrogen isolation layer comprises RZ, wherein R is Si or Cr, Z is at least one of O, C, and N, and when Z comprises O, the O element content percentage is ≥20%, when Z comprises C, the C element content percentage is 20%~30%, when Z is N, the N element content percentage is ≥80%, when Z comprises N and other elements, the N element content ratio is ≥50%; or, the material of the hydrogen isolation layer comprises an aluminum oxide layer containing hydrogen elements, and the element content of hydrogen elements in the aluminum oxide layer is ≤2×10 21 atoms / cm 3 ; The hydrogen isolation layer is arranged between the functional layer and the silicon substrate.

Description

Technical Field

[0001] The present application relates to the field of solar cells, and in particular to a solar cell and a preparation method thereof, and a photovoltaic module. Background Art

[0002] Photovoltaic modules are modules that are obtained by electrically connecting and encapsulating a number of solar cells. When used outdoors, photovoltaic modules will inevitably be exposed to ultraviolet rays, which will lead to the problem of module power attenuation due to the aging of materials such as sealant films. To solve this problem, the current main method is to modify materials such as sealant films to slow down the module power attenuation caused by ultraviolet radiation, but these measures have limited effect on improving the anti-ultraviolet ability of photovoltaic modules. It is necessary to further improve the anti-ultraviolet ability of photovoltaic modules. Summary of the invention

[0003] The present application discloses a solar cell and a preparation method thereof, and a photovoltaic module. The anti-ultraviolet capability of the solar cell itself is improved by improving the structure of the solar cell, thereby more reliably improving the anti-ultraviolet capability of the photovoltaic module.

[0004] In a first aspect, the present application provides a solar cell, the solar cell comprising:

[0005] Silicon substrate;

[0006] A functional layer is disposed on the surface of the silicon substrate, wherein the functional layer is a hydrogen-containing layer, an anti-reflection layer or a doping layer;

[0007] A hydrogen isolation layer, wherein the thickness of the hydrogen isolation layer is 0.5 nm to 5 nm; wherein the material of the hydrogen isolation layer includes RZ, wherein R is Si or Cr, and Z is at least one of O, C, and N, and when Z includes O, the element content percentage of O in the RZ is greater than or equal to 22%, when Z includes C, the element content percentage of C in the RZ is 20% to 30%, when Z is N, the element content percentage of N in the RZ is greater than or equal to 80%, and when Z includes N and other elements, the element content ratio of N in the RZ is greater than or equal to 50%; or, the material of the hydrogen isolation layer includes an aluminum oxide layer containing hydrogen, and the element content of the hydrogen element in the aluminum oxide layer is ≤2×10 21 atoms / cm 3 ;

[0008] The hydrogen isolation layer is disposed between the functional layer and the silicon substrate.

[0009] Further, the functional layer has a Si-H bond, R is Si, Z is O, and the element content percentage of O in RZ is greater than or equal to 50%; and / or,

[0010] The R is Si, the Z is C, and the element content percentage of C in the RZ is 25% to 29.95%; and / or,

[0011] R is Si, Z is N, and the element content percentage of N in RZ is greater than or equal to 85%; and / or,

[0012] The R is Si, the Z is O and N, the element content percentage of O in the RZ is greater than or equal to 22%, and the element content percentage of N in the RZ is greater than or equal to 50%.

[0013] Furthermore, the hydrogen permeability of the hydrogen isolation layer is 1×10 -7 mol·m -1 ·S -1 ·Pa (-1 / 2) ~1×10 - 14 mol·m -1 ·S -1 ·Pa (-1 / 2) .

[0014] Furthermore, the content of hydrogen in the functional layer is 6.0×10 21 atoms / cm 3 ~1.0×10 22 atoms / cm 3 , and the content of hydrogen in the functional layer after ultraviolet irradiation is 5.6×10 21 atoms / cm 3 ~8.0×10 21 atoms / cm 3 .

[0015] Further, the hydrogen isolation layer includes one or more layers of an aluminum oxide layer, a silicon oxide layer, a silicon carbide layer, a chromium nitride layer, a chromium oxide layer, a silicon oxynitride layer, and a silicon nitride layer.

[0016] Furthermore, the functional layer includes a first functional layer disposed on the light-receiving surface of the silicon substrate, the first functional layer is a first anti-reflection layer, the first anti-reflection layer has at least two layers and includes a silicon nitride layer and / or a silicon nitride oxide layer; along the thickness direction of the first anti-reflection layer, the first anti-reflection layer has a first maximum hydrogen content layer, and the content percentage of hydrogen element in the first maximum hydrogen content layer is 6.0×10 21 atoms / cm 3 ~1.0×10 22 atoms / cm 3 ;

[0017] and / or,

[0018] The functional layer includes a second functional layer disposed on the backlight surface of the silicon substrate, the second functional layer is a second anti-reflection layer, the second anti-reflection layer has at least two layers and includes a silicon nitride layer and / or a silicon nitride oxide layer; along the thickness direction of the second anti-reflection layer, the second anti-reflection layer has a second maximum hydrogen content layer, and the content percentage of hydrogen element in the second maximum hydrogen content layer is 6.0×10 21 atoms / cm 3 ~1.0×10 22 atoms / cm 3 .

[0019] Furthermore, the hydrogen isolation layer includes a first hydrogen isolation layer provided on the light-receiving surface of the silicon substrate, and the solar cell further includes:

[0020] The light-receiving surface passivation layer is located on the light-receiving surface of the silicon substrate, the light-receiving surface passivation layer is arranged between the first hydrogen isolation layer and the silicon substrate, and the light-receiving surface passivation layer is an aluminum oxide layer.

[0021] Furthermore, the hydrogen isolation layer includes a second hydrogen isolation layer provided on the backlight surface of the silicon substrate, and the solar cell further includes:

[0022] A dielectric layer and a doped polysilicon layer are arranged between the backlight surface of the silicon substrate and the second hydrogen isolation layer, wherein the dielectric layer is arranged close to the backlight surface of the silicon substrate, and the doped polysilicon layer is arranged close to the second hydrogen isolation layer.

[0023] Furthermore, the functional layer includes a first functional layer disposed on the light-receiving surface of the silicon substrate, the first functional layer is a first doped layer, the first doped layer is a doped amorphous silicon layer or a doped microcrystalline silicon layer, and the content percentage of hydrogen in the first doped layer is 1.0×10 19 atoms / cm 3 ~1.0×10 20 atoms / cm 3 and / or,

[0024] The functional layer includes a second functional layer disposed on the backlight surface of the silicon substrate, the second functional layer is a second doped layer, the second doped layer is a doped amorphous silicon layer or a doped microcrystalline silicon layer, and the content percentage of hydrogen in the second doped layer is 1.0×10 19 atoms / cm 3 ~1.0×10 20 atoms / cm 3 .

[0025] Further, the hydrogen isolation layer includes a first hydrogen isolation layer provided on the light-receiving surface of the silicon substrate, and the solar cell further includes: a first passivation layer, the first passivation layer being provided between the light-receiving surface of the silicon substrate and the hydrogen isolation layer; and / or,

[0026] The hydrogen isolation layer includes a second hydrogen isolation layer arranged on the backlight surface of the silicon substrate. The solar cell also includes a second passivation layer, which is arranged between the backlight surface of the silicon substrate and the second hydrogen isolation layer.

[0027] In a second aspect, the present application provides a method for preparing a solar cell as described in the first aspect, wherein the method for preparing a solar cell comprises the following steps:

[0028] depositing the hydrogen isolation layer on the silicon substrate;

[0029] The functional layer is deposited on the hydrogen barrier layer.

[0030] Furthermore, the hydrogen isolation layer is prepared by PECVD process, and the preparation conditions include:

[0031] The deposition time is 10 s~60 s, and the deposition temperature is 450℃~550℃;

[0032] The deposition pressure is 1300 mTorr~1650 mTorr, the RF power is 9000 W~15000 W, the RF power is turned on for 20 ms~50 ms, and the RF power is turned off for 500 ms~1000 ms.

[0033] Further, the hydrogen isolation layer is a silicon oxynitride layer, and the preparation conditions include: a deposition time of 10 s to 60 s, a deposition temperature of 450°C to 550°C; the flow rate of the gas source includes: SiH4 is 700 sccm to 1200 sccm, NH3 is 5000 sccm to 9000 sccm, and N2O is 2000 sccm to 4000 sccm; the deposition pressure is 1300 mTorr to 1600 mTorr, the RF power is 9000 watts to 15000 watts, the RF power is turned on for 20 ms to 50 ms, and the RF power is turned off for 500 ms to 1000 ms;

[0034] or,

[0035] The hydrogen isolation layer is a silicon nitride layer, and the preparation conditions include: a deposition time of 20 s to 40 s, a deposition temperature of 450° C. to 550° C.; the flow rate of the gas source includes: SiH4 of 900 sccm to 1200 sccm, and NH3 of 10000 sccm to 12000 sccm; a deposition pressure of 1500 mTorr to 1650 mTorr, a radio frequency power of 13000 watts to 15000 watts, a radio frequency power on of 20 ms to 50 ms, and a radio frequency power off of 700 ms to 800 ms;

[0036] or,

[0037] The hydrogen isolation layer is a silicon oxide layer, and the silicon oxide layer is prepared by a PECVD process, and the preparation conditions include: a deposition time of 10 s to 30 s, a deposition temperature of 450° C. to 550° C.; the flow rate of the gas source includes: SiH4 of 600 sccm to 900 sccm, N2O of 8000 sccm to 11000 sccm; the deposition pressure is 1100 mTorr to 1300 mTorr, the RF power is 12000 watts to 15000 watts, the RF power is turned on for 20 ms to 50 ms, and the RF power is turned off for 700 ms to 800 ms;

[0038] or,

[0039] The hydrogen isolation layer is a composite layer of a silicon oxynitride layer and a silicon nitride layer, and the silicon oxynitride layer is close to the silicon substrate, and the silicon nitride layer is away from the silicon substrate, wherein the preparation conditions of the silicon oxynitride layer include: a deposition time of 10 s to 60 s, a deposition temperature of 450° C. to 550° C.; the flow rate of the gas source includes: SiH4 is 700 sccm to 1200 sccm, NH3 is 5000 sccm to 9000 sccm, and N2O is 2000 sccm to 4000 sccm; the deposition pressure is 1300 mTorr to 1600 mTorr, the RF power is 9000 watts to 15000 watts, the RF power is turned on for 20 ms to 50 ms, and the RF power is turned off for 500 ms to 1000 ms; the preparation conditions of the silicon nitride layer include: a deposition time of 20 s to 40 s, the deposition temperature is 450℃~550℃; the flow rates of the gas sources include: SiH4 is 900 sccm~1200 sccm, and NH3 is 10000 sccm~12000 sccm; the deposition pressure is 1500 mTorr~1650 mTorr, the RF power is 13000 W~15000 W, the RF power is turned on for 20 ms~50 ms, and the RF power is turned off for 700 ms~800 ms.

[0040] In a third aspect, the present application provides a photovoltaic module, wherein the photovoltaic module includes the solar cell as described in the first aspect, or the photovoltaic module includes a solar cell manufactured by the method for manufacturing a solar cell as described in the second aspect.

[0041] Compared with the prior art, this application has at least the following beneficial effects:

[0042] The present application finds that for solar cells containing hydrogen elements in the functional layer, a hydrogen isolation layer of specific material and specific thickness is added between the functional layer and the silicon substrate, and by controlling the percentage content of oxygen elements, carbon elements and / or nitrogen elements in the hydrogen isolation layer, the hydrogen elements in the functional layer can be effectively isolated, thereby effectively improving the UV resistance of the solar cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0044] Figure 1 It is a schematic diagram of the structure of a solar cell according to an embodiment of the present application;

[0045] Figure 2 It is a schematic diagram of the structure of another solar cell according to an embodiment of the present application.

[0046] Description of reference numerals:

[0047] 1. Silicon substrate; 2. Functional layer; 21. Anti-reflection layer; 211. First anti-reflection layer; 212. Second anti-reflection layer; 22. Doped layer; 221. First doped layer; 222. Second doped layer; 3. Hydrogen isolation layer; 31. First hydrogen isolation layer; 32. Second hydrogen isolation layer; 4. Light-receiving surface passivation layer; 5. Dielectric layer; 6. Doped polysilicon layer; 71. First passivation layer; 72. Second passivation layer. DETAILED DESCRIPTION

[0048] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0049] In the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0050] In addition, some of the above terms may be used to express other meanings in addition to indicating a direction or position relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.

[0051] In addition, the terms "installed", "set", "provided with", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0052] In addition, the terms "first", "second", etc. are mainly used to distinguish different devices, elements or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise specified, "plurality" means two or more.

[0053] When photovoltaic modules are used outdoors, long-term exposure to ultraviolet rays causes some of the materials in the modules to age easily, resulting in a decrease in the module output power, which will have a significant impact on the reliability of the photovoltaic modules for long-term operation. The relevant technology mainly improves the performance of the EVA encapsulation film and photovoltaic glass of photovoltaic modules to reduce the impact of ultraviolet radiation on photovoltaic modules.

[0054] However, a large number of solar cells are used in photovoltaic modules, and ultraviolet radiation will have a great impact on the hydrogen passivation effect of solar cells, resulting in a decrease in the power of solar cells after ultraviolet radiation. Therefore, from the perspective of solar cells, the embodiments of the present application improve the structure of solar cells themselves to improve their ability to resist ultraviolet attenuation, so that the photovoltaic modules obtained by using a large number of solar cells in series and / or in parallel also have better resistance to ultraviolet attenuation, and thus have higher photoelectric conversion efficiency and output power, and improve the reliability of photovoltaic modules under long-term outdoor working conditions.

[0055] In a first aspect, the present application provides a solar cell, Figure 1 and Figure 2 As shown, Figure 1 and Figure 2 The schematic diagrams of the structures of two optional solar cells in the embodiments of the present application are shown respectively. Figure 1 The electrodes are not shown. Figure 2 The TCO layer is not shown. The solar cell comprises:

[0056] Silicon substrate 1;

[0057] The functional layer 2 is disposed on the surface of the silicon substrate 1, the functional layer 2 is a hydrogen-containing layer, and the functional layer 2 is an anti-reflection layer 21 or a doping layer 22;

[0058] A hydrogen isolation layer 3, the thickness of the hydrogen isolation layer 3 is 0.5 nm to 5 nm; wherein the material of the hydrogen isolation layer 3 includes RZ, wherein R is Si or Cr, and Z is at least one of O, C, and N, and when Z includes O, the element content percentage of O in RZ is greater than or equal to 22%, when Z includes C, the element content percentage of C in RZ is 20% to 30%, when Z is N, the element content percentage of N in RZ is greater than or equal to 80%, and when Z includes N and other elements, the element content ratio of N in RZ is greater than or equal to 50%; or, the material of the hydrogen isolation layer 3 includes an aluminum oxide layer containing hydrogen, and the element content of hydrogen in the aluminum oxide layer is ≤2×10 21 atoms / cm 3 ;

[0059] The hydrogen isolation layer 3 is disposed between the functional layer 2 and the silicon substrate 1 .

[0060] Among them, Si refers to silicon, Cr refers to chromium, O refers to oxygen, C refers to carbon, and N refers to nitrogen. In addition, it can be understood that the material of the hydrogen isolation layer 3 includes RZ, and the material of the hydrogen isolation layer 3 can be made entirely of RZ material, or the main material used to form the hydrogen isolation layer 3 is RZ and includes a small amount of other impurity components. Both of the above situations allow the hydrogen isolation layer 3 to reflect the properties of the RZ material. Optionally, when R is Si and Z is one or more of the elements O, C or N, the hydrogen isolation layer 3 is a composite layer of one or more layers of a silicon oxide layer, a silicon carbide layer, a silicon nitride layer or a silicon oxynitride layer having a specific Z element content ratio. When R is Cr, Z is O or N, and the hydrogen isolation layer 3 is a chromium nitride layer or a chromium oxide layer having a specific Z element content ratio.

[0061] Wherein, when Z includes O, the percentage of the element content of O in RZ is greater than or equal to 22%, including any point value within the numerical range, for example, when Z includes O, the percentage of the element content of O in RZ is 22%, 25%, 30%, 40%, 50%, 55% or 60%. Z including O means that Z can be only oxygen element, or can also include elements such as nitrogen element or carbon element in addition to oxygen element.

[0062] Wherein, when Z includes C, the element content percentage of C in RZ is 20% to 30%, including any point value within the numerical range, for example, when Z includes C, the element content percentage of C in RZ is 20%, 22%, 25%, 28%, 29% or 30%. Z including C means that Z can be only carbon element, or can also include elements such as nitrogen element or oxygen element in addition to carbon element.

[0063] Wherein, when Z is N, the percentage of the element content of N in RZ is greater than or equal to 80%, including any value within the numerical range, for example, when Z is N, the percentage of the element content of N in RZ is 80%, 82%, 85%, 87% or 90%. When Z includes N and other elements, the percentage of the element content of N in RZ is greater than or equal to 50%, including any value within the numerical range, for example, when Z includes N and other elements, the percentage of the element content of N in RZ is 50%, 52%, 55%, 57% or 59%. Z including N and other elements means that Z includes not only nitrogen, but also oxygen or nitrogen, or includes both oxygen and nitrogen.

[0064] The thickness of the hydrogen isolation layer 3 is 0.5 nm to 5 nm, including any value within the thickness range, for example, the thickness of the hydrogen isolation layer 3 is 0.5 nm, 0.8 nm, 1.0 nm, 1.2 nm, 1.5 nm, 1.8 nm, 2.0 nm, 2.2 nm, 2.5 nm, 3.0 nm, 3.5 nm, 4.0 nm, 4.5 nm or 5.0 nm. Preferably, the thickness of the hydrogen isolation layer 3 is 1 nm to 1.5 nm. The hydrogen isolation layer has a stronger anti-ultraviolet ability at this thickness.

[0065] The present application has discovered that for solar cells containing hydrogen elements in the functional layer 2, a hydrogen isolation layer 3 of a specific material and a specific thickness is added between the functional layer 2 and the silicon substrate 1, and by controlling the percentage content of oxygen elements, carbon elements and / or nitrogen elements in the hydrogen isolation layer 3, the hydrogen elements in the functional layer 2 can be effectively isolated, thereby effectively improving the UV resistance of the solar cell.

[0066] Among them, the functional layer 2 is an anti-reflection layer 21 or a doping layer 22 containing hydrogen elements. When the hydrogen isolation layer 3 is not provided, the hydrogen elements in the functional layer 2 will diffuse toward the direction of the silicon substrate 1 during the preparation of the solar cell, and then form Si-H bonds with the silicon elements in the silicon substrate 1. However, these Si-H bonds are easily broken under ultraviolet irradiation conditions, which has a significant impact on the open circuit voltage and fill factor, making the anti-ultraviolet ability of the solar cell worse. In order to solve the above problems, the present application adds a hydrogen isolation layer 3 that can block the passage of hydrogen elements between the functional layer 2 and the silicon substrate 1. Due to the blocking effect of the hydrogen isolation layer 3, the hydrogen elements in the functional layer 2 that can form Si-H bonds with the silicon substrate 1 are reduced, thereby reducing the number of Si-H bonds. In this way, since the Si-H bonds on the surface of the silicon substrate 1 are reduced, the number of Si-H bonds that are broken due to ultraviolet irradiation is also reduced, thereby weakening the influence of ultraviolet irradiation on the hydrogen passivation effect, making the performance of the solar cell less affected by ultraviolet irradiation, thereby improving the anti-ultraviolet ability of the solar cell.

[0067] In the embodiment of the present application, the functional layer 2 has Si-H bonds. Si-H bonds are more likely to break under ultraviolet irradiation conditions, making it easier for the functional layer 2 to produce more free hydrogen ions due to the breaking of Si-H bonds under ultraviolet irradiation conditions. Without the isolation of the hydrogen isolation layer 3, these hydrogen ions are more likely to diffuse toward the silicon substrate 1, resulting in the redistribution of hydrogen elements, that is, ultraviolet irradiation will bring more significant ultraviolet attenuation problems to the solar cells with the above characteristics. The hydrogen isolation layer 3 of the embodiment of the present application can effectively alleviate the above problems, and has a more significant improvement effect on the ultraviolet attenuation problem of the solar cell with the above functional layer 2.

[0068] It is understandable that the solar cell of the embodiment of the present application may also include structures such as an emitter and an electrode located between the silicon substrate 1 and the light-receiving surface passivation layer 4. Since these structures can be arranged in a conventional manner and are not the inventive point of the present application, they will not be described in detail in the present application.

[0069] In a first optional embodiment, R is Si, Z is O, and the content percentage of O in RZ is greater than or equal to 50%. x, the hydrogen isolation layer 3 is a silicon oxide layer with a specific oxygen content percentage. When the percentage of the oxygen content in the silicon oxide layer is greater than or equal to 50%, the film layer has a large amount of oxygen elements, which makes the Si-O bond take precedence over the Si-H bond. Therefore, the hydrogen content of the silicon oxide layer itself with the specific oxygen content percentage is very small. At the same time, the silicon oxide layer can also effectively prevent the hydrogen elements in the functional layer 2 from penetrating in the direction of the silicon substrate 1, reduce the number of Si-H bonds formed after the hydrogen elements in the functional layer 2 reach the surface of the silicon substrate 1, and then reduce the large number of Si-H bonds caused by ultraviolet irradiation. Breakage, thereby weakening the impact of ultraviolet irradiation on the performance of solar cells, helps to improve the anti-ultraviolet ability of solar cells.

[0070] In a second optional embodiment, R is Si, Z is C, and the element content percentage of C in RZ is 20% to 30%. That is, RZ is SiC x , the hydrogen isolation layer 3 is a silicon carbide layer with a specific carbon content ratio. The dangling bonds of C or Si in the silicon carbide layer can combine with H from the functional layer 2 to form a strong chemical bond, thereby fixing the hydrogen element of the functional layer 2 in the silicon carbide layer, reducing the probability of the hydrogen element in the functional layer 2 reaching the silicon substrate 1, thereby playing an effective hydrogen isolation role. In this way, since the number of Si-H bonds formed after the hydrogen element in the functional layer 2 reaches the surface of the silicon substrate 1 is reduced, the problem of a large number of Si-H bonds breaking due to ultraviolet irradiation is reduced, and the resistance of solar cells to ultraviolet irradiation is improved.

[0071] In a third optional embodiment, R is Si, Z is N, and the percentage of N in RZ is greater than or equal to 85%. x, the hydrogen isolation layer 3 is a silicon nitride layer with a specific nitrogen content ratio. The silicon nitride layer can be divided into a silicon nitride layer rich in nitrogen and a silicon nitride layer rich in silicon according to the different content ratios of nitrogen in the film layer. When the percentage of nitrogen in the silicon nitride layer is greater than or equal to 85%, it is a silicon nitride layer rich in nitrogen. The presence of more nitrogen, on the one hand, allows more N in the silicon nitride layer to combine with H in the functional layer 2 to form NH bonds, which plays a role in fixing and intercepting H in the functional layer 2; on the other hand, it makes the Si-N bonds and NH bonds in the silicon nitride layer more, and the Si-H bonds become less. Since the stability of the NH bond is better under ultraviolet irradiation conditions, the stability of the Si-H is worse and it is easier to break the bond due to ultraviolet irradiation, so the reduction of the Si-H bond reduces the influence of ultraviolet irradiation on the solar cell. Therefore, by combining the free hydrogen element in the functional layer 2 and reducing the Si-H bond with poor ultraviolet stability, the isolation effect of the hydrogen element in the functional layer 2 is improved, and the ultraviolet attenuation problem of the solar cell is improved. It should be noted that in solar cells such as TOPCon solar cells, the anti-reflection layer 21 adopts a silicon nitride composite layer, but these silicon nitride layers are silicon nitride layers rich in silicon. This type of silicon nitride layer is rich in Si-H bonds and does not have good hydrogen isolation capabilities. Therefore, it is more likely to have obvious ultraviolet attenuation problems, which is completely different from the nitrogen-rich silicon nitride layer used in the embodiments of the present application.

[0072] In a fourth optional embodiment, R is Si, Z is O and N, the content percentage of O in RZ is greater than or equal to 22%, and the content percentage of N in RZ is greater than or equal to 50%. x N y , the hydrogen isolation layer 3 is a silicon oxynitride layer with a specific oxygen and nitrogen content ratio. When the oxygen content percentage in the silicon oxynitride layer is greater than or equal to 22% and the nitrogen content percentage is greater than or equal to 50%, the film layer can effectively prevent the hydrogen element in the functional layer 2 from penetrating toward the silicon substrate 1. Secondly, the hydrogen content of the film layer itself is relatively small, which can reduce the number of Si-H bonds formed after the hydrogen element in the functional layer 2 reaches the surface of the silicon substrate 1, thereby reducing the large number of Si-H bonds broken due to ultraviolet irradiation, thereby weakening the impact of ultraviolet irradiation on the performance of solar cells, and helping to improve the anti-ultraviolet ability of solar cells.

[0073] In addition, as mentioned above, RZ can also be an aluminum oxide layer with a specific hydrogen content ratio. The hydrogen content in the aluminum oxide layer is less than or equal to 2×10 21 atoms / cm 3When the hydrogen element is relatively less and the dangling bonds are relatively more, the H from the functional layer 2 is more likely to form -OH in this special aluminum oxide layer and be fixed and intercepted. It should be noted that in solar cells such as TOPCon solar cells, the ALD (Atomic Layer Deposition) process is used to deposit an amorphous aluminum oxide film as a passivation layer. However, the H content in this aluminum oxide passivation layer is high and the film layer is relatively loose, and it cannot effectively isolate the H from the functional layer 2. Instead, it will allow these free H to pass through the aluminum oxide passivation layer. Therefore, this aluminum oxide passivation layer does not have a good hydrogen isolation ability, which is completely different from the low-hydrogen aluminum oxide layer used in the embodiment of the present application.

[0074] Furthermore, the hydrogen permeability of the hydrogen isolation layer 3 is 1×10 -7 mol·m -1 ·S -1 ·Pa (-1 / 2) ~1×10 -14 mol·m -1 ·S -1 ·Pa (-1 / 2) When the hydrogen permeability of the hydrogen isolation layer 3 is controlled within the above range, it can better balance the interception of hydrogen and the passivation of the silicon substrate surface, avoiding excessive interception of hydrogen to affect the passivation effect, and avoiding too little interception of hydrogen to fail to reduce the attenuation of ultraviolet radiation.

[0075] Furthermore, after ultraviolet irradiation, the content of hydrogen in the functional layer decreased by 6.7%~20.0%.

[0076] Furthermore, the content of hydrogen in the functional layer 2 is 6.0×10 21 atoms / cm 3 ~1.0×10 22 atoms / cm 3 , and the hydrogen content in the functional layer 2 after ultraviolet irradiation is 5.6×10 21 atoms / cm 3 ~8.0×10 21 atoms / cm 3 Due to the effective isolation of the hydrogen isolation layer 3, the hydrogen content in the functional layer 2 does not change significantly before and after ultraviolet irradiation, indicating that the hydrogen in the functional layer 2 does not diffuse and migrate into the silicon substrate 1 in large quantities. In this way, a large number of Si-H bonds will not break after ultraviolet irradiation, thereby better alleviating the ultraviolet attenuation problem of the solar cell and further improving the anti-ultraviolet ability of the solar cell.

[0077] The above UV irradiation conditions include 60±5℃, wavelength range 280nm~400nm, irradiation intensity 200W / m 2 , continuous and stable irradiation of 11 kWh. Since the solar cell is used to receive sunlight in an outdoor environment, and the ultraviolet irradiation intensity under normal sunlight irradiation conditions is lower than the above ultraviolet irradiation conditions, when the solar cell of the embodiment of the present application is used for outdoor photovoltaic power generation or energy storage, the hydrogen isolation layer can also ensure that the hydrogen content in the functional layer will not change significantly due to the isolation.

[0078] Furthermore, the solar cell of the embodiment of the present application may be a TOPCon solar cell or a HJT solar cell.

[0079] Combine the following Figure 1 The technical solution of the solar cell of the embodiment of the present application being a TOPCon solar cell is further explained. For TOPCon solar cells, when the light-receiving surface of the silicon substrate 1 uses a hydrogen-rich silicon nitride layer, it has a better anti-reflection effect, and the backlight surface of such solar cells uses a dielectric layer 5 and a doped polysilicon layer 6 to balance the conductivity and passivation capabilities of the solar cell. However, the Si-H bonds in the solar cells of the above structure are easily broken under ultraviolet irradiation conditions, resulting in a significant deterioration in the passivation performance of the surface of the silicon substrate 1, and a more obvious decrease in the open circuit voltage and fill factor. It can be seen that the ultraviolet attenuation problem of TOPCon solar cells is more prominent, and after the embodiment of the present application adds a hydrogen isolation layer 3 between the silicon substrate 1 and the functional layer 2 of the TOPCon solar cell, the ultraviolet attenuation problem of the TOPCon solar cell can be more significantly improved.

[0080] In the solar cell, the functional layer 2 is an anti-reflection layer 21, and the anti-reflection layer 21 can be arranged on the light-receiving surface, the backlight surface, or both surfaces of the solar cell. The hydrogen isolation layer 3 can be arranged between the light-receiving surface of the silicon substrate 1 and the anti-reflection layer 21 located on one side of the light-receiving surface, or between the backlight surface of the silicon substrate 1 and the anti-reflection layer 21 located on the backlight surface, or can be arranged on both surfaces.

[0081] Further, the functional layer 2 includes a first functional layer disposed on the light-receiving surface of the silicon substrate 1, the first functional layer is a first anti-reflection layer 211, and the first anti-reflection layer 211 has at least two layers and includes a silicon nitride layer and / or a silicon oxynitride layer. In other words, the first anti-reflection layer 211 is a composite layer, and the first anti-reflection layer 211 can be a stack of multiple silicon nitride layers, or a stack of multiple silicon oxynitride layers, or a composite stack of different numbers of silicon nitride layers and silicon oxynitride layers, for example, the first anti-reflection layer 211 can be a stack of three silicon nitride layers and one silicon oxynitride layer.

[0082] In addition, different film layers of the first anti-reflection layer 211 have different hydrogen content. For example, when the first anti-reflection layer 211 is a stack of three silicon nitride layers and one silicon oxynitride layer, each silicon nitride layer and silicon oxynitride layer may have different hydrogen content. Along the thickness direction of the first anti-reflection layer 211, the first anti-reflection layer 211 has a first maximum hydrogen content layer, and the hydrogen content in the first maximum hydrogen content layer is 6.0×10 21 atoms / cm 3 ~1.0×10 22 atoms / cm 3 Here, the first maximum hydrogen content layer refers to the layer with the highest hydrogen content among the film layers constituting the first anti-reflection layer 211 .

[0083] The proportion of the hydrogen element in the first maximum hydrogen content layer increases the Si-H bonds in the first anti-reflection layer 211, thereby making the ultraviolet attenuation problem of the solar cell having the first anti-reflection layer 211 more serious. By adding the hydrogen isolation layer 3 of the embodiment of the present application between the first anti-reflection layer 211 and the silicon substrate 1, the ultraviolet attenuation problem of the solar cell can be more significantly solved, and the anti-ultraviolet ability of the solar cell can be further improved.

[0084] Further, the functional layer 2 includes a second functional layer disposed on the backlight surface of the silicon substrate 1, the second functional layer is a second anti-reflection layer 212, and the second anti-reflection layer 212 has at least two layers and includes a silicon nitride layer and / or a silicon oxynitride layer. In other words, the second anti-reflection layer 212 is a composite layer, and the second anti-reflection layer 212 can be a stack of multiple silicon nitride layers, or a stack of multiple silicon oxynitride layers, or a composite stack of different numbers of silicon nitride layers and silicon oxynitride layers, for example, the first anti-reflection layer 211 can be a stack of three silicon nitride layers and one silicon oxynitride layer.

[0085] In addition, different film layers of the second anti-reflection layer 212 have different hydrogen content. For example, when the second anti-reflection layer 212 is a stack of three silicon nitride layers and one silicon oxynitride layer, each silicon nitride layer and silicon oxynitride layer may have different hydrogen content. Along the thickness direction of the second anti-reflection layer 212, the second anti-reflection layer 212 has a second maximum hydrogen content layer, and the hydrogen content in the second maximum hydrogen content layer is 6.0×10 21 atoms / cm 3 ~1.0×10 22 atoms / cm 3 Here, the second maximum hydrogen content layer refers to the layer with the highest hydrogen content among the film layers constituting the second anti-reflection layer 212 .

[0086] The proportion of the hydrogen element in the second maximum hydrogen content layer increases the number of Si-H bonds in the second anti-reflection layer 212, thereby making the ultraviolet attenuation problem of the solar cell having the second anti-reflection layer 212 more serious. By adding the hydrogen isolation layer 3 of the embodiment of the present application between the second anti-reflection layer 212 and the silicon substrate 1, the ultraviolet attenuation problem of the solar cell can be more significantly solved, and the anti-ultraviolet ability of the solar cell can be further improved.

[0087] Furthermore, the hydrogen isolation layer 3 includes a first hydrogen isolation layer 31 disposed on the light-receiving surface of the silicon substrate 1, and the solar cell further includes: a light-receiving surface passivation layer 4, located on the light-receiving surface of the silicon substrate 1, the light-receiving surface passivation layer 4 is disposed between the first hydrogen isolation layer 31 and the silicon substrate 1, and the light-receiving surface passivation layer 4 is an aluminum oxide layer. Since the first hydrogen isolation layer 31 is located on the outside of the light-receiving surface passivation layer 4 (i.e., located on the side of the light-receiving surface passivation layer 4 away from the silicon substrate 1), the first hydrogen isolation layer 31 only blocks the H in the first anti-reflection layer 211, and does not affect the light-receiving surface passivation layer 4 located on the inner side thereof to play its role, thereby achieving the purpose of both ensuring the passivation effect of the solar cell and effectively weakening the ultraviolet attenuation.

[0088] Among them, in terms of the passivation effect, the field passivation effect of the aluminum oxide layer plays a major passivation role on the silicon substrate 1, and the Si-H bonds formed by the H in the first anti-reflection layer 211 after passing through the aluminum oxide layer and reaching the silicon substrate 1 only play an auxiliary chemical passivation role. Therefore, although the amount of H in the first anti-reflection layer 211 passing through the aluminum oxide layer is reduced, it does not affect the aluminum oxide layer to play its leading role in field passivation, so the solar cell can still maintain good passivation performance. Among them, in terms of the anti-ultraviolet effect, as mentioned above, since the H in the first anti-reflection layer 211 is effectively isolated by the hydrogen isolation layer 3, the Si-H bonds formed on the silicon substrate 1 are reduced, so the Si-H bonds broken by ultraviolet irradiation are also reduced, so that the performance attenuation of the solar cell under ultraviolet irradiation is reduced, and the anti-ultraviolet ability is stronger.

[0089] Further, the hydrogen isolation layer 3 includes a second hydrogen isolation layer 32 disposed on the backlight surface of the silicon substrate 1, and the solar cell further includes: a dielectric layer 5 and a doped polysilicon layer 6 disposed between the backlight surface of the silicon substrate 1 and the second hydrogen isolation layer 32, wherein the dielectric layer 5 is disposed close to the backlight surface of the silicon substrate 1, and the doped polysilicon layer 6 is disposed close to the second hydrogen isolation layer 32. The dielectric layer 5 may be a silicon oxide layer, and the doped polysilicon layer 6 may be a P-type doped polysilicon layer 6 or an N-type doped polysilicon layer 6. The dielectric layer 5 and the doped polysilicon layer 6 form a passivation contact structure.

[0090] Since the second hydrogen isolation layer 32 is located on the outside of the doped polysilicon layer 6 (i.e., on the side of the doped crystalline silicon layer away from the silicon substrate 1), the second hydrogen isolation layer 32 only blocks the H in the second anti-reflection layer 212, and does not affect the doped polysilicon layer 6 located on the inner side thereof to play its role, thereby effectively weakening the ultraviolet attenuation without affecting the function of the doped polysilicon layer 6.

[0091] Combine the following Figure 2 The technical solution of the solar cell in the embodiment of the present application being a HJT solar cell is further explained. Figure 2 It is a schematic diagram of the structure of the HJT solar cell of the embodiment of the present application, in which the TCO layer located on the doping layer is omitted. For HJT solar cells, the light-receiving side and the backlight side of the silicon substrate are respectively provided with doping layers of opposite conductivity types. When the doping layer uses an amorphous silicon layer or a microcrystalline silicon layer, it has a better technical effect. However, these layers have more Si-H bonds, which are easily broken by ultraviolet radiation, resulting in a more obvious decrease in the open circuit voltage and fill factor of such solar cells. It can be seen that the ultraviolet attenuation problem of HJT solar cells is more prominent, and after the embodiment of the present application adds a hydrogen isolation layer between the silicon substrate and the doping layer of the HJT solar cell, the ultraviolet attenuation problem of the HJT solar cell can be more significantly improved.

[0092] In the solar cell, the functional layer 2 is a doping layer 22, and the doping layer 22 includes a first doping layer 221 and a second doping layer 222 respectively arranged on the light-receiving surface and the backlight surface of the silicon substrate 1. The hydrogen isolation layer 3 can be arranged between the light-receiving surface of the silicon substrate 1 and the first doping layer 221, or between the backlight surface of the silicon substrate 1 and the second doping layer 222, or can be arranged on both sides.

[0093] Furthermore, the functional layer 2 includes a first functional layer disposed on the light-receiving surface of the silicon substrate 1, the first functional layer is a first doping layer 221, the first doping layer 221 is a doped amorphous silicon layer or a doped microcrystalline silicon layer, and the content of hydrogen in the first doping layer 221 is 1.0×10 19 atoms / cm 3 ~1.0×10 20 atoms / cm 3 .

[0094] Furthermore, the functional layer 2 includes a second functional layer disposed on the backlight surface of the silicon substrate 1, the second functional layer is a second doping layer 222, the second doping layer 222 is a doped amorphous silicon layer or a doped microcrystalline silicon layer, and the content percentage of hydrogen in the second doping layer 222 is 1.0×10 19 atoms / cm 3 ~1.0×10 20 atoms / cm 3 .

[0095] In the doping layer 22 having the above-mentioned hydrogen element content percentage, there are more Si-H bonds, and the problem of ultraviolet attenuation is more significant. Therefore, by adding a hydrogen isolation layer 3 of an embodiment of the present application between the above-mentioned doping layer 22 and the silicon substrate 1, the ultraviolet attenuation problem of the above-mentioned solar cell can be better solved, and the ultraviolet resistance of the above-mentioned solar cell can be further improved.

[0096] Further, the hydrogen isolation layer 3 includes a first hydrogen isolation layer 31 disposed on the light-receiving surface of the silicon substrate 1, and the solar cell further includes: a first passivation layer 71, and the first passivation layer 71 is disposed between the light-receiving surface of the silicon substrate 1 and the hydrogen isolation layer 3. The hydrogen isolation layer 3 includes a second hydrogen isolation layer 32 disposed on the backlight surface of the silicon substrate 1, and the solar cell further includes: a second passivation layer 72, and the second passivation layer 72 is disposed between the backlight surface of the silicon substrate 1 and the second hydrogen isolation layer 32. The first passivation layer 71 and the second passivation layer 72 may be intrinsic amorphous silicon layers.

[0097] The first hydrogen isolation layer 31 is located on the outside of the first passivation layer 71 (i.e., located on the side of the first passivation layer 71 away from the silicon substrate 1), and the second hydrogen isolation layer 32 is located on the outside of the second passivation layer 72 (i.e., located on the side of the second passivation layer 72 away from the silicon substrate 1). Therefore, the first hydrogen isolation layer 31 only blocks the H in the first doping layer 221, and the second hydrogen isolation layer 32 only blocks the H in the second doping layer 222, and does not affect the first passivation layer 71 and the second passivation layer 72 on the inner side to play their roles, thereby achieving the purpose of both ensuring the passivation effect of the solar cell and effectively weakening the ultraviolet attenuation.

[0098] In a second aspect, an embodiment of the present application provides a method for preparing a solar cell as described in the first aspect, the method comprising the following steps:

[0099] depositing a hydrogen barrier layer on a silicon substrate;

[0100] A functional layer is deposited on the hydrogen barrier layer.

[0101] Furthermore, the hydrogen isolation layer is prepared by a PECVD process, and the preparation conditions include:

[0102] The deposition time is 10 s~60 s, and the deposition temperature is 450℃~550℃;

[0103] The deposition pressure is 1300 mTorr~1650 mTorr, the RF power is 9000 W~15000 W, the RF power is turned on for 20 ms~50 ms, and the RF power is turned off for 500 ms~1000 ms.

[0104] The switching time of the RF power source refers to the switching time of the power pulse.

[0105] In a first optional embodiment, the hydrogen isolation layer is a silicon oxynitride layer, and the preparation conditions include: a deposition time of 10 s to 60 s, a deposition temperature of 450°C to 550°C; the flow rates of the gas sources include: SiH4 of 700 sccm to 1200 sccm, NH3 of 5000 sccm to 9000 sccm, and N2O of 2000 sccm to 4000 sccm; the deposition pressure is 1300 mTorr to 1600 mTorr, the RF power is 9000 watts to 15000 watts, the RF power is turned on for 20 ms to 50 ms, and the RF power is turned off for 500 ms to 1000 ms.

[0106] In a second optional embodiment, the hydrogen isolation layer is a silicon nitride layer, and the preparation conditions include: a deposition time of 20s~40s, a deposition temperature of 450℃~550℃; the flow rate of the gas source includes: SiH4 of 900sccm~1200sccm, NH3 of 10000sccm~12000sccm; the deposition pressure is 1500mTorr~1650mTorr, the RF power is 13000W~15000W, the RF power is turned on for 20ms~50ms, and the RF power is turned off for 700ms~800ms.

[0107] In a third optional embodiment, the hydrogen isolation layer is a silicon oxide layer, and the silicon oxide layer is prepared by a PECVD process, and the preparation conditions include: a deposition time of 10 s to 30 s, a deposition temperature of 450°C to 550°C; the flow rate of the gas source includes: SiH4 of 600 sccm to 900 sccm, and N2O of 8000 sccm to 11000 sccm; the deposition pressure is 1100 mTorr to 1300 mTorr, the RF power is 12000 watts to 15000 watts, the RF power is turned on for 20 ms to 50 ms, and the RF power is turned off for 700 ms to 800 ms.

[0108] In a fourth optional embodiment, the hydrogen isolation layer is a composite layer of a silicon oxynitride layer and a silicon nitride layer, and the silicon oxynitride layer is close to the silicon substrate and the silicon nitride layer is away from the silicon substrate, wherein the preparation conditions of the silicon oxynitride layer include: a deposition time of 10 s to 60 s, a deposition temperature of 450°C to 550°C; the flow rate of the gas source includes: SiH4 is 700 sccm to 1200 sccm, NH3 is 5000 sccm to 9000 sccm, and N2O is 2000 sccm to 4000 sccm; the deposition pressure is 1300 mTorr to 1600 mTorr, the RF power is 9000 watts to 15000 watts, the RF power is turned on for 20 ms to 50 ms, and the RF power is turned off for 500 ms to 1000 ms; the preparation conditions of the silicon nitride layer include: a deposition time of 20 s to 40 s, the deposition temperature is 450℃~550℃; the flow rates of the gas sources include: SiH4 is 900 sccm~1200 sccm, and NH3 is 10000 sccm~12000 sccm; the deposition pressure is 1500mTorr~1650 mTorr, the RF power is 13000 W~15000 W, the RF power is turned on for 20 ms~50 ms, and the RF power is turned off for 700ms~800 ms.

[0109] In solar cells such as TOPCon solar cells, when making films such as silicon oxynitride layers, silicon nitride layers or silicon oxide layers, although PECVD processes can be used, the thickness of the film layer and the hydrogen content in the film layer are increased mainly by controlling a longer deposition time and more silane gas source flow, thereby playing a corresponding anti-reflection or passivation role. However, in the embodiments of the present application, by controlling a shorter deposition time and less silane gas source flow, the thickness of the film layer can be reduced and the hydrogen content in the film layer can be reduced, so as to achieve the purpose of controlling the content of specific oxygen elements, carbon elements or nitrogen elements, so that the film layer has the function of fixing and blocking hydrogen elements, which can ultimately help to weaken the impact of ultraviolet attenuation on solar cells and improve the anti-ultraviolet ability of solar cells.

[0110] In a third aspect, an embodiment of the present application provides a photovoltaic module, which includes the solar cell as described in the first aspect, or the photovoltaic module includes the solar cell made by the method for making the solar cell as described in the second aspect. A photovoltaic module is formed by connecting and packaging a plurality of the above solar cells in series and / or in parallel.

[0111] The embodiments of the present application are further described below in conjunction with specific embodiments and test results.

[0112] Example 1

[0113] This embodiment provides a solar cell, and the preparation method thereof comprises the following steps:

[0114] A semi-finished solar cell product is provided; the semi-finished solar cell product comprises an N-type silicon substrate, a boron-doped layer with a thickness of 1.0 μm and an aluminum oxide passivation layer with a thickness of 3.5 nm, which are sequentially arranged on the light-receiving surface of the silicon substrate, a silicon oxide dielectric layer with a thickness of 1.5 nm and a phosphorus-doped polysilicon layer with a thickness of 120 nm, which are sequentially arranged on the backlight surface of the silicon substrate, wherein the boron-doped layer is obtained by thermal diffusion doping, the aluminum oxide passivation layer is obtained by ALD deposition, and the silicon oxide dielectric layer and the phosphorus-doped polysilicon layer are obtained by PECVD.

[0115] A first hydrogen isolation layer is deposited on the aluminum oxide passivation layer, and the deposition conditions include: a deposition time of 10 s, a deposition temperature of 450°C to 550°C, a SiH4 flow rate of 700 sccm to 1200 sccm, an NH3 flow rate of 5000 sccm to 9000 sccm, an N2O flow rate of 2000 sccm to 4000 sccm, a pressure of 1300 mTorr to 1600 mTorr, an RF power of 9000 watts to 15000 watts, an RF power supply on for 20 ms to 50 ms, and an RF power supply off for 500 ms to 1000 ms; a silicon oxynitride layer is deposited;

[0116] A composite first functional layer is deposited on the first hydrogen isolation layer. The deposition conditions include: depositing in sequence at a deposition temperature of 450° C. to 550° C.:

[0117] The first silicon nitride film layer has a deposition time of 60 s to 90 s, a SiH4 flow rate of 1800 sccm to 2500 sccm, an NH3 flow rate of 5500 scmm to 7500 sccm, a pressure of 1500 mTorr to 1650 mTorr, an RF power of 13000 W to 14000 W, an RF power on time of 20 ms to 50 ms, and an RF power off time of 700 ms to 800 ms;

[0118] The second silicon nitride film layer has a deposition time of 100 s to 150 s, a SiH4 flow rate of 1000 sccm to 1200 sccm, an NH3 flow rate of 7500 sccm to 8500 sccm, a pressure of 1500 mTorr to 1650 mTorr, an RF power of 13000 W to 15000 W, an RF power on time of 20 ms to 50 ms, and an RF power off time of 500 ms to 600 ms.

[0119] The third silicon nitride film layer has a deposition time of 130 s to 180 s, a SiH4 flow rate of 900 sccm to 1200 sccm, an NH3 flow rate of 9000 sccm to 12000 sccm, a pressure of 1500 mTorr to 1650 mTorr, an RF power of 13000 W to 15000 W, an RF power on time of 20 ms to 50 ms, and an RF power off time of 500 ms to 600 ms;

[0120] The deposition time of silicon oxynitride film on the light-receiving surface is 250 s~350 s, the SiH4 flow rate is 800 sccm~1100 sccm, the NH3 flow rate is 2000 sccm~5000 sccm, the N2O flow rate is 6000 sccm~9000 sccm, the pressure is 1100 mTorr~1300 mTorr, the RF power is 12000 W~15000 W, the RF power is turned on for 20 ms~50 ms, and the RF power is turned off for 800 ms~1000 ms;

[0121] The silicon oxide film layer on the light-receiving surface has a deposition time of 90 s to 170 s, a SiH4 flow rate of 600 sccm to 900 sccm, a N2O flow rate of 8000 sccm to 11000 sccm, a pressure of 1100 mTorr to 1300 mTorr, an RF power of 12000 W to 15000 W, an RF power on time of 20 ms to 50 ms, and an RF power off time of 800 ms to 1000 ms;

[0122] A composite second functional layer is deposited on the phosphorus-doped polysilicon layer. The deposition conditions include: depositing in sequence at a deposition temperature of 500° C. to 540° C.:

[0123] The fourth silicon nitride film layer has a deposition time of 60 s to 90 s, a SiH4 flow rate of 1800 sccm to 2500 sccm, an NH3 flow rate of 5500 sccm to 7500 sccm, a pressure of 1500 mTorr to 1650 mTorr, an RF power of 13000 W to 14000 W, an RF power on time of 20 ms to 50 ms, and an RF power off time of 700 ms to 800 ms;

[0124] The fifth silicon nitride layer has a deposition time of 50 s to 100 s, a SiH4 flow rate of 1000 sccm to 1200 sccm, an NH3 flow rate of 5000 sccm to 7000 sccm, a pressure of 1500 mTorr to 1650 mTorr, an RF power of 13000 W to 15000 W, an RF power on time of 20 ms to 50 ms, and an RF power off time of 500 ms to 600 ms.

[0125] The sixth silicon nitride film layer has a deposition time of 70 s to 150 s, a SiH4 flow rate of 900 sccm to 1200 sccm, an NH3 flow rate of 7000 sccm to 8500 sccm, a pressure of 1500 mTorr to 1650 mTorr, an RF power of 13000 W to 15000 W, an RF power on time of 20 ms to 50 ms, and an RF power off time of 500 ms to 600 ms.

[0126] The seventh silicon nitride film layer has a deposition time of 200 s to 400 s, a SiH4 flow rate of 900 sccm to 1200 sccm, an NH3 flow rate of 10000 sccm to 12000 sccm, a pressure of 1500 mTorr to 1650 mTorr, an RF power of 13000 W to 15000 W, an RF power on time of 20 ms to 50 ms, and an RF power off time of 500 ms to 600 ms;

[0127] Make electrodes for the light-receiving side and the backlight side.

[0128] Embodiment 2~embodiment 4

[0129] The only difference between Example 2 to Example 4 and Example 1 is that the deposition time of the first hydrogen isolation layer is 20 s, 40 s, and 60 s, respectively.

[0130] Example 5

[0131] The difference between this embodiment and embodiment 1 is that the deposition conditions of the first hydrogen isolation layer are different. In this embodiment, the conditions for depositing the first hydrogen isolation layer include: deposition time 20 s, deposition temperature 450°C~550°C, SiH4 flow rate 900sccm~1200sccm, NH3 flow rate 10000sccm~12000sccm, pressure 1500mTorr~1650mTorr, RF power 13000W~15000W, RF power on 20ms~50ms, RF power off 700ms~800ms; the silicon nitride layer is deposited.

[0132] Example 6

[0133] The only difference between this embodiment and embodiment 5 is that the deposition time of the first hydrogen isolation layer is 40 s.

[0134] Example 7

[0135] The difference between this embodiment and embodiment 1 is that the deposition conditions of the first hydrogen isolation layer are different. In this embodiment, the conditions for depositing the first hydrogen isolation layer include: deposition time 20 s, deposition temperature 450°C~550°C, SiH4 flow rate 600sccm~900sccm, N2O flow rate 8000sccm~11000sccm, pressure 1100mTorr~1300mTorr, RF power 12000W~15000W, RF power on 20ms~50ms, RF power off 700ms~800ms; the silicon oxide layer is deposited.

[0136] Example 8

[0137] The difference between this embodiment and embodiment 1 is that the deposition conditions of the first hydrogen isolation layer are different. In this embodiment, the conditions for depositing the first hydrogen isolation layer include sequentially depositing at a deposition temperature of 450° C. to 550° C.:

[0138] Silicon oxynitride layer, deposition time 20 s, SiH4 flow rate 700 sccm~1200 sccm, NH3 flow rate 5000 sccm~9000 sccm, N2O flow rate 2000 sccm~4000 sccm, pressure 1300 mTorr~1600 mTorr, RF power 9000 W~15000 W, RF power on 20 ms~50 ms, RF power off 500 ms~1000 ms;

[0139] Silicon nitride layer, deposition time 20 s, SiH4 flow rate 900 sccm~1200 sccm, NH3 flow rate 10000 sccm~12000 sccm, pressure 1500 mTorr~1650 mTorr, RF power 13000 W~15000 W, RF power on 20 ms~50 ms, RF power off 700 ms~800 ms.

[0140] Example 9

[0141] The difference between this embodiment and embodiment 1 is that: the first hydrogen isolation layer is not deposited, and the composite first functional layer is directly deposited on the aluminum oxide passivation layer; the second hydrogen isolation layer is deposited between the phosphorus-doped polysilicon layer on the backlight side and the second functional layer, and the deposition conditions include:

[0142] The deposition time is 20 s, the deposition temperature is 450℃~550℃, the SiH4 flow rate is 700 sccm~1200 sccm, the NH3 flow rate is 5000 sccm~9000 sccm, the N2O flow rate is 2000 sccm~4000 sccm, the pressure is 1300 mTorr~1600 mTorr, the RF power is 9000 watts~15000 watts, the RF power is turned on for 20 ms~50 ms, and the RF power is turned off for 500 ms~1000ms; a silicon nitride oxide layer is deposited.

[0143] Example 10

[0144] The difference between this embodiment and embodiment 9 is that the deposition conditions of the second hydrogen isolation layer are different. In this embodiment, the conditions for depositing the second hydrogen isolation layer include: deposition time 20 s, deposition temperature 450°C~550°C, SiH4 flow rate 900sccm~1200sccm, NH3 flow rate 10000sccm~12000sccm, pressure 1500mTorr~1650mTorr, RF power 13000W~15000W, RF power on 20ms~50ms, RF power off 700ms~800ms; the silicon nitride layer is deposited.

[0145] Embodiment 11

[0146] The difference between this embodiment and embodiment 1 is that, in addition to the first hydrogen isolation layer deposited on the light-receiving surface, a second hydrogen isolation layer is deposited between the phosphorus-doped polysilicon layer and the second functional layer on the backlight surface, and the deposition conditions of the second hydrogen isolation layer include:

[0147] The deposition time is 20 s, the deposition temperature is 450℃~550℃, the SiH4 flow rate is 700 sccm~1200 sccm, the NH3 flow rate is 5000 sccm~9000 sccm, the N2O flow rate is 2000 sccm~4000 sccm, the pressure is 1300 mTorr~1600 mTorr, the RF power is 9000 watts~15000 watts, the RF power is turned on for 20 ms~50 ms, and the RF power is turned off for 500 ms~1000ms; a silicon nitride oxide layer is deposited.

[0148] Example 12

[0149] The difference between this embodiment and embodiment 1 is that the deposition conditions of the first hydrogen isolation layer are different. In this embodiment, the conditions for depositing the first hydrogen isolation layer include: deposition time 20 s, deposition temperature 300°C~350°C, percentage of trimethylaluminum introduced 60%~100%, N2O flow 5000 sccm~10000 sccm, pressure 1200 mTorr~1600 mTorr, RF power 5000 watts~7000 watts, RF power on 10 ms~30 ms, RF power off 1200 ms~1600 ms; aluminum oxide layer is deposited.

[0150] The percentage of trimethylaluminum refers to the volume percentage of trimethylaluminum in the carrier gas (for example, nitrogen as the carrier gas) when trimethylaluminum is carried into the reaction chamber of PECVD.

[0151] Embodiment 13

[0152] The difference between this embodiment and embodiment 1 is that the deposition conditions of the first hydrogen isolation layer are different. In this embodiment, the conditions for depositing the first hydrogen isolation layer include: deposition time 20 s, deposition temperature 300°C~350°C, Cr(CO)6 flow rate 1000 sccm~2000 sccm, O2 flow rate 2000 sccm~4000 sccm, pressure 1200 mTorr~1600 mTorr, RF power 5000 watts~7000 watts, RF power on 10 ms~30 ms, RF power off 1200 ms~1600 ms; chromium oxide layer is deposited.

[0153] Embodiment 14

[0154] The difference between this embodiment and embodiment 1 is that the deposition conditions of the first hydrogen isolation layer are different. In this embodiment, the conditions for depositing the first hydrogen isolation layer include: deposition time 20 s, deposition temperature 300°C~350°C, SiH4 flow rate 2000sccm~3000sccm, CH4 flow rate 2000sccm~3000sccm, pressure 1200mTorr~1600mTorr, RF power 5000W~7000W, RF power on 10ms~30ms, RF power off 1200ms~1600ms; the silicon carbide layer is deposited.

[0155] Embodiment 15

[0156] This embodiment provides a HJT solar cell, and the preparation method thereof comprises the following steps:

[0157] A semi-finished solar cell is provided; the semi-finished solar cell comprises an N-type silicon substrate, an intrinsic amorphous silicon film with a thickness of 5 nm disposed on the light-receiving surface and the backlight surface of the silicon substrate, respectively, and the intrinsic amorphous silicon films deposited on the two surfaces serve as a passivation layer;

[0158] A hydrogen isolation layer is deposited on the passivation layer, and the deposition conditions include: a deposition time of 30 s, a deposition temperature of 150°C to 250°C, a SiH4 flow rate of 700 sccm to 1200 sccm, an NH3 flow rate of 5000 sccm to 9000 sccm, an N2O flow rate of 2000 sccm to 4000 sccm, a pressure of 1300 mTorr to 1600 mTorr, an RF power of 9000 watts to 15000 watts, an RF power supply on for 20 ms to 50 ms, and an RF power supply off for 500 ms to 1000 ms; a silicon oxynitride layer is deposited;

[0159] Depositing a doped layer on the hydrogen isolation layer: depositing a 10 nm thick doped P-type amorphous silicon layer on the light-receiving side, and depositing a 10 nm thick N-type amorphous silicon layer on the backlight side; wherein the passivation layer, the hydrogen isolation layer, and the doped layer are all deposited by a PECVD process;

[0160] Depositing a transparent conductive oxide film on the doped layer: a transparent conductive oxide film is deposited on the doped layer by a PVD magnetron sputtering process.

[0161] Comparative Example 1

[0162] This comparative example provides a solar cell. The only difference between this comparative example and Example 1 is that this comparative example does not contain a first hydrogen isolation layer, and the first functional layer is directly made on the aluminum oxide passivation layer.

[0163] Comparative Example 2

[0164] The difference between this comparative example and Example 1 is that the deposition conditions of the first hydrogen isolation layer are different. In this comparative example, the conditions for depositing the first hydrogen isolation layer include: deposition time 20 s, deposition temperature 450°C~550°C, SiH4 flow rate 500sccm~1000sccm, NH3 flow rate 1500sccm~3000sccm, pressure 1500mTorr~1650mTorr, RF power 13000W~15000W, RF power on 20ms~50ms, RF power off 700ms~800ms; the silicon nitride layer is deposited.

[0165] Comparative Example 3

[0166] The difference between this comparative example and Example 1 is that the deposition conditions of the first hydrogen isolation layer are different. In this comparative example, the conditions for depositing the first hydrogen isolation layer include: deposition time 20 s, deposition temperature 450°C~550°C, SiH4 flow rate 800sccm~1200sccm, NH3 flow rate 5600sccm~8400sccm, pressure 1500mTorr~1650mTorr, RF power 13000W~15000W, RF power on 20ms~50ms, RF power off 700ms~800ms; the silicon nitride layer is deposited.

[0167] Comparative Example 4

[0168] The difference between this comparative example and Example 1 is that the deposition conditions of the first hydrogen isolation layer are different. In this comparative example, the conditions for depositing the first hydrogen isolation layer include: deposition time 20 s, deposition temperature 450°C~550°C, SiH4 flow rate 500 sccm~1000 sccm, NH3 flow rate 1300 sccm~2600 sccm, N2O flow rate 500 sccm~1000 sccm, pressure 1300 mTorr~1600 mTorr, RF power 9000 watts~15000 watts, RF power on 20 ms~50 ms, RF power off 500 ms~1000 ms; silicon oxynitride layer is deposited.

[0169] Performance Test:

[0170] Element content test: SIMS (Secondary Ion Mass Spectrometry) was used to test the element content in the hydrogen isolation layer.

[0171] Hydrogen permeability test: Select the target hydrogen isolation layer, install it in the hydrogen permeation chamber, and use the vacuum leak detection method to test the permeation chamber for leaks. Evacuate both ends of the permeation chamber, fill hydrogen into one side of the target membrane layer, and fill the other end with deionized water. After a certain period of time, take a water sample from the sampling port and test the H content in it. According to the formula Q=Φ / d·P (1 / 2) To calculate the hydrogen permeability; where Q is the permeation rate, the unit is mol·m -2 ×S -1 ; Φ is the permeability mol·m -1 ·S -1 ·Pa (-1 / 2) ; d is the thickness of the permeate layer m, and P is the pressure at the high concentration end of the permeate. When the membrane thickness and the high concentration end of the permeate are known, Φ can be calculated as long as Q is measured within a certain period of time.

[0172] The test results of element content and hydrogen permeability are shown in Table 1.

[0173] UV attenuation rate of bare chip solar cells: 10 finished solar cells are taken from each group for IV test, numbered and placed in a UV irradiation box. The test conditions include: 60±5℃, wavelength range 280nm~400nm, irradiation intensity 200W / m 2 After continuous and stable irradiation of 11kWh, take out the battery cell and test IV again. The percentage of efficiency attenuation before and after irradiation is the UV attenuation rate.

[0174] UV attenuation rate of photovoltaic modules: The cells were packaged into 72-panel double-glass modules, using EPE+EVA combination packaging. After the modules were completed, they were left to stand for 24 hours before IV testing. They were then placed in a UV irradiation box. The test conditions included: 60±5℃, wavelength range 280 nm~400 nm, irradiation intensity 200 W / m 2 After continuous and stable irradiation for 60 kWh, take out the components and test IV again. The percentage of efficiency attenuation before and after irradiation is the UV attenuation rate.

[0175] Table 1: Test results of element contents and hydrogen permeability of hydrogen isolation layers in Examples and Comparative Examples

[0176]

[0177] The test results of UV attenuation rate of bare-chip solar cells and photovoltaic modules are shown in Table 2.

[0178] Table 2: Test results of UV attenuation rates of the embodiments and comparative examples

[0179]

[0180] By comparing the experimental results of Examples 1 to 15 and Comparative Example 1, it can be seen that the embodiments of the present application can effectively block the passage of hydrogen by adding a hydrogen isolation layer, and significantly improve the anti-ultraviolet attenuation ability of solar cells and photovoltaic modules. By further comparing the above embodiments with Comparative Examples 2 to 4, it can be seen that not all silicon nitride layers and silicon oxynitride layers have good hydrogen resistance. It is necessary to control the content of elements such as nitrogen and oxygen in the hydrogen isolation layer to effectively block hydrogen and improve the resistance to ultraviolet attenuation. In addition, by further comparing the various embodiments of the present application, it can be seen that when a composite film layer (such as a stack of silicon oxynitride layers and silicon nitride layers) is used as a hydrogen isolation layer and a hydrogen isolation layer is set on both sides of the solar cell, the solar cell has a stronger anti-ultraviolet ability; when chromium oxide or silicon carbide is used as a hydrogen isolation layer, the solar cell has a stronger anti-ultraviolet ability; in addition, increasing the thickness of the silicon oxynitride layer to 1 nm~1.5 nm also helps to improve the anti-ultraviolet ability.

[0181] The above is a detailed introduction to the technical solutions disclosed in the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the technical solutions and core inventions of the embodiments of the present application. At the same time, for those skilled in the art, according to the ideas of the present application, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A solar cell, characterized in that: The solar cell comprises: Silicon substrate; A functional layer is disposed on the surface of the silicon substrate, wherein the functional layer is a hydrogen-containing layer, an anti-reflection layer or a doping layer; A hydrogen isolation layer, wherein the thickness of the hydrogen isolation layer is 0.5 nm to 5 nm; wherein the material of the hydrogen isolation layer includes RZ, wherein R is Si or Cr, and Z is at least one of O, C, and N, and when Z includes O, the element content percentage of O in the RZ is greater than or equal to 22%, when Z includes C, the element content percentage of C in the RZ is 20% to 30%, when Z is N, the element content percentage of N in the RZ is greater than or equal to 80%, and when Z includes N and other elements, the element content ratio of N in the RZ is greater than or equal to 50%; or, the material of the hydrogen isolation layer includes an aluminum oxide layer containing hydrogen, and the element content of the hydrogen element in the aluminum oxide layer is ≤2×10 21 atoms / cm 3 ; The hydrogen isolation layer is disposed between the functional layer and the silicon substrate.

2. The solar cell according to claim 1, characterized in that: The functional layer has a Si-H bond, R is Si, Z is O, and the element content percentage of O in RZ is greater than or equal to 50%; and / or, The R is Si, the Z is C, and the element content percentage of C in the RZ is 25% to 29.95%; and / or, R is Si, Z is N, and the element content percentage of N in RZ is greater than or equal to 85%; and / or, The R is Si, the Z is O and N, the element content percentage of O in the RZ is greater than or equal to 22%, and the element content percentage of N in the RZ is greater than or equal to 50%.

3. The solar cell according to claim 1, characterized in that: The hydrogen permeability of the hydrogen isolation layer is 1×10 - 7 mol·m -1 ·S -1 ·Pa (-1 / 2) ~1×10 -14 mol·m -1 ·S -1 ·Pa (-1 / 2) .

4. The solar cell according to claim 1, characterized in that: After ultraviolet irradiation, the content of hydrogen in the functional layer decreases by 6.7% to 20.0%; and / or, The content of hydrogen in the functional layer is 6.0×10 21 atoms / cm 3 ~1.0×10 22 atoms / cm 3 , and the content of hydrogen in the functional layer after ultraviolet irradiation is 5.6×10 21 atoms / cm 3 ~8.0×10 21 atoms / cm 3 .

5. The solar cell according to claim 1, characterized in that: The hydrogen isolation layer includes one or more layers of an aluminum oxide layer, a silicon oxide layer, a silicon carbide layer, a chromium nitride layer, a chromium oxide layer, a silicon oxynitride layer, and a silicon nitride layer.

6. The solar cell according to any one of claims 1 to 5, characterized in that: The functional layer comprises a first functional layer disposed on the light-receiving surface of the silicon substrate, the first functional layer being a first anti-reflection layer, the first anti-reflection layer having at least two layers and comprising a silicon nitride layer and / or a silicon nitride oxide layer; along the thickness direction of the first anti-reflection layer, the first anti-reflection layer has a first maximum hydrogen content layer, and the content of hydrogen in the first maximum hydrogen content layer is 6.0×10 21 atoms / cm 3 ~1.0×10 22 atoms / cm 3 ; and / or, The functional layer includes a second functional layer disposed on the backlight surface of the silicon substrate, the second functional layer is a second anti-reflection layer, the second anti-reflection layer has at least two layers and includes a silicon nitride layer and / or a silicon nitride oxide layer; along the thickness direction of the second anti-reflection layer, the second anti-reflection layer has a second maximum hydrogen content layer, and the content of hydrogen in the second maximum hydrogen content layer is 6.0×10 21 atoms / cm 3 ~1.0×10 22 atoms / cm 3 .

7. The solar cell according to claim 6, characterized in that: The hydrogen isolation layer includes a first hydrogen isolation layer provided on the light-receiving surface of the silicon substrate, and the solar cell further includes: The light-receiving surface passivation layer is located on the light-receiving surface of the silicon substrate, the light-receiving surface passivation layer is arranged between the first hydrogen isolation layer and the silicon substrate, and the light-receiving surface passivation layer is an aluminum oxide layer.

8. The solar cell according to claim 6, characterized in that: The hydrogen isolation layer includes a second hydrogen isolation layer provided on the backlight surface of the silicon substrate, and the solar cell further includes: A dielectric layer and a doped polysilicon layer are arranged between the backlight surface of the silicon substrate and the second hydrogen isolation layer, wherein the dielectric layer is arranged close to the backlight surface of the silicon substrate, and the doped polysilicon layer is arranged close to the second hydrogen isolation layer.

9. The solar cell according to any one of claims 1 to 5, characterized in that: The functional layer includes a first functional layer disposed on the light-receiving surface of the silicon substrate, the first functional layer is a first doped layer, the first doped layer is a doped amorphous silicon layer or a doped microcrystalline silicon layer, and the content of hydrogen in the first doped layer is 1.0×10 19 atoms / cm 3 ~1.0×10 20 atoms / cm 3 and / or, The functional layer includes a second functional layer disposed on the backlight surface of the silicon substrate, the second functional layer is a second doped layer, the second doped layer is a doped amorphous silicon layer or a doped microcrystalline silicon layer, and the content of hydrogen in the second doped layer is 1.0×10 19 atoms / cm 3 ~1.0×10 20 atoms / cm 3 .

10. The solar cell according to claim 9, characterized in that: The hydrogen isolation layer includes a first hydrogen isolation layer disposed on the light-receiving surface of the silicon substrate, and the solar cell further includes: a first passivation layer, the first passivation layer is disposed between the light-receiving surface of the silicon substrate and the hydrogen isolation layer; and / or, The hydrogen isolation layer includes a second hydrogen isolation layer arranged on the backlight surface of the silicon substrate. The solar cell also includes a second passivation layer, which is arranged between the backlight surface of the silicon substrate and the second hydrogen isolation layer.

11. A method for preparing a solar cell according to any one of claims 1 to 10, characterized in that: The method for preparing the solar cell comprises the following steps: depositing the hydrogen isolation layer on the silicon substrate; The functional layer is deposited on the hydrogen barrier layer.

12. The method for preparing a solar cell according to claim 11, characterized in that: The hydrogen isolation layer is prepared by PECVD process, and the preparation conditions include: The deposition time is 10 s~60 s, and the deposition temperature is 450℃~550℃; The deposition pressure is 1300 mTorr~1650 mTorr, the RF power is 9000 W~15000 W, the RF power is turned on for 20 ms~50 ms, and the RF power is turned off for 500 ms~1000 ms.

13. The method for preparing a solar cell according to claim 12, characterized in that: The hydrogen isolation layer is a silicon oxynitride layer, and the preparation conditions include: a deposition time of 10 s to 60 s, a deposition temperature of 450° C. to 550° C.; the flow rate of the gas source includes: SiH4 of 700 sccm to 1200 sccm, NH3 of 5000 sccm to 9000 sccm, and N2O of 2000 sccm to 4000 sccm; the deposition pressure is 1300 mTorr to 1600 mTorr, the RF power is 9000 watts to 15000 watts, the RF power is turned on for 20 ms to 50 ms, and the RF power is turned off for 500 ms to 1000 ms; or, The hydrogen isolation layer is a silicon nitride layer, and the preparation conditions include: a deposition time of 20 s to 40 s, a deposition temperature of 450° C. to 550° C.; the flow rate of the gas source includes: SiH4 of 900 sccm to 1200 sccm, and NH3 of 10000 sccm to 12000 sccm; the deposition pressure is 1500 mTorr to 1650 mTorr, the RF power is 13000 watts to 15000 watts, the RF power is turned on for 20 ms to 50 ms, and the RF power is turned off for 700 ms to 800 ms; or, The hydrogen isolation layer is a silicon oxide layer, and the silicon oxide layer is prepared by a PECVD process, and the preparation conditions include: a deposition time of 10 s to 30 s, a deposition temperature of 450° C. to 550° C.; the flow rate of the gas source includes: SiH4 of 600 sccm to 900 sccm, N2O of 8000 sccm to 11000 sccm; the deposition pressure is 1100 mTorr to 1300 mTorr, the RF power is 12000 watts to 15000 watts, the RF power is turned on for 20 ms to 50 ms, and the RF power is turned off for 700 ms to 800 ms; or, The hydrogen isolation layer is a composite layer of a silicon oxynitride layer and a silicon nitride layer, and the silicon oxynitride layer is close to the silicon substrate, and the silicon nitride layer is away from the silicon substrate, wherein the preparation conditions of the silicon oxynitride layer include: a deposition time of 10s~60s, a deposition temperature of 450℃~550℃; the flow rate of the gas source includes: SiH4 is 700sccm~1200sccm, NH3 is 5000sccm~9000sccm, and N2O is 2000sccm~4000sccm; the deposition pressure is 1300mTorr~1600mTorr, the RF power is 9000W~15000W, the RF power is turned on for 20ms~50ms, and the RF power is turned off for 500ms~1000ms; the preparation conditions of the silicon nitride layer include: a deposition time of 20s~40 s, the deposition temperature is 450℃~550℃; the flow rates of the gas sources include: SiH4 is 900 sccm~1200 sccm, and NH3 is 10000 sccm~12000 sccm; the deposition pressure is 1500 mTorr~1650 mTorr, the RF power is 13000 W~15000 W, the RF power is turned on for 20 ms~50 ms, and the RF power is turned off for 700 ms~800 ms.

14. A photovoltaic module, characterized in that: The photovoltaic module comprises the solar cell according to any one of claims 1 to 10, or the photovoltaic module comprises the solar cell manufactured by the method for manufacturing a solar cell according to any one of claims 11 to 13.

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