Preparation method of Topcon battery tunneling oxide layer and Topcon battery
After growing the tunnel oxide layer by thermal oxidation, combined with H2 and N2 repair treatment, the problem of monitoring the density and uniformity of the tunnel oxide layer was solved, the contaminant particles in the oxide layer were removed, and the passivation effect and conversion efficiency of Topcon cells were improved.
Patent Information
- Application Number
- CN202410963415.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-18
- Publication Date
- 2025-10-24
AI Technical Summary
Existing Topcon battery fabrication processes cannot effectively monitor the growth thickness, density, and uniformity of the tunnel oxide layer in real time. Furthermore, the tunnel oxide layer prepared by thermal oxidation has loose and weak areas, and contains contaminating impurity particles.
After growing the tunnel oxide layer using the thermal oxidation method, it is repaired by H2 and N2, with the temperature controlled at 600℃~800℃ and the repair reaction time and flow rate at 1min~5min and 3slm~6slm, respectively, to remove contaminant particles in the oxide layer and improve the density and uniformity of the oxide layer.
It achieves high density and uniformity of the tunnel oxide layer, removes contaminant particles in the oxide layer, and improves passivation effect and battery conversion efficiency.
Smart Images
Figure CN120835629A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of solar cells, in particular to a preparation method of a Topcon cell tunneling oxide layer and a Topcon cell. BACKGROUND
[0002] The existing Topcon cell preparation process cannot effectively monitor the growth thickness, compactness and uniformity of the tunneling oxide layer in real time, and the film quality of the tunneling oxide layer cannot be monitored. In addition, although the tunneling oxide layer prepared by the thermal oxidation method has better passivation effect than the tunneling oxide layer prepared by the PECVD (plasma enhanced chemical vapor deposition) method, the oxide layer still has loose and weak places, and there are also contaminant particles in the oxide layer.
[0003] Therefore, the present application is proposed. SUMMARY
[0004] One of the purposes of the present application is to provide a preparation method of a Topcon cell tunneling oxide layer, which can grow a tunneling oxide layer with better thickness matching, higher compactness and better uniformity, and can remove contaminant particles adsorbed in the oxide layer to make the surface cleaner.
[0005] The second purpose of the present application is to provide a Topcon cell with better passivation effect and higher cell conversion efficiency.
[0006] In order to achieve the above purposes of the present application, the following technical solutions are adopted:
[0007] In a first aspect, a preparation method of a Topcon cell tunneling oxide layer comprises the following steps:
[0008] After the cell piece grows the tunneling oxide layer, the tunneling oxide layer is repaired by H2 and N2 to obtain a repaired tunneling oxide layer.
[0009] The temperature of the repair treatment is 600-800℃.
[0010] Further, the tunneling oxide layer comprises silicon dioxide.
[0011] Further, the thickness of the tunneling oxide layer is 0.5-2nm.
[0012] Further, the method for growing the tunneling oxide layer comprises a thermal oxidation method.
[0013] Preferably, the thermal oxidation method comprises an LPCVD thermal oxidation method.
[0014] Further, the temperature of the thermal oxidation method is 600-800℃.
[0015] Preferably, the oxidizing gas used in the thermal oxidation method comprises O2.
[0016] Further, the repairing method comprises the following steps:
[0017] First, H2 is introduced to repair the tunneling oxide layer, and then N2 is introduced to repair the tunneling oxide layer.
[0018] Further, the flow rate of H2 is 8 slm-11 slm, and the reaction time is 1 min-5 min.
[0019] Further, the flow rate of N2 is 3 slm-6 slm, and the reaction time is 3 min-6 min.
[0020] In the second aspect, the Topcon cell is prepared by the preparation method of any one of the above.
[0021] Further, the conversion efficiency of the Topcon cell is 26.50%-26.60%.
[0022] Compared with the prior art, the present application has at least the following beneficial effects:
[0023] The preparation method of the Topcon cell tunneling oxide layer provided by the present application introduces H2 and N2 to repair the loose and weak parts of the oxide layer after growing the tunneling oxide layer, and hydrogen passivates the surface dangling bonds of the oxide layer under specific temperature conditions (600℃-800℃), which makes the oxide layer more dense and uniform, effectively improves the passivation effect, and effectively removes the adsorbed pollution impurity particles in the oxide layer, which makes the surface cleanliness higher, thereby improving the conversion efficiency of the cell.
[0024] The Topcon cell provided by the present application has better passivation effect and higher cell conversion efficiency. BRIEF DESCRIPTION OF DRAWINGS
[0025] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor.
[0026] Figure 1 The process flow chart for repairing the tunneling oxide layer by using H2 and N2 is provided for an embodiment of the present application. DETAILED DESCRIPTION
[0027] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.
[0028] According to a first aspect of the present invention, a method for preparing a tunneling oxide layer of a Topcon battery is provided, comprising the following steps:
[0029] After the cell grows a tunnel oxide layer, the tunnel oxide layer is repaired by H2 and N2 to obtain a repaired tunnel oxide layer;
[0030] Among them, the temperature of the repair treatment can be 600℃~800℃, and its typical but non-limiting temperatures are, for example, 600℃, 650℃, 700℃, 750℃, and 800℃. The appropriate temperature can ensure the hydrogen passivation of the dangling bonds on the surface of the oxide layer, fully improve the density and uniformity of the oxide layer, and at the same time ensure the effective removal of the pollutant impurity particles adsorbed in the oxide layer, fully improve the surface cleanliness; if the temperature is too high, it will lead to a violent repair reaction, too high density, and worse uniformity; if the temperature is too low, it will lead to insufficient repair reaction, and it is difficult to achieve the effect of fully improving the density and uniformity of the oxide layer.
[0031] In summary, the preparation method of the tunneling oxide layer of the Topcon battery provided by the present invention is to introduce H2 and N2 after growing the tunneling oxide layer to repair the loose and weak parts of the oxide layer. Under specific temperature conditions (600℃~800℃), hydrogen passivates the dangling bonds on the surface of the oxide layer, which makes the oxide layer denser and more uniform, effectively improves the passivation effect, and can also effectively remove the contaminant impurity particles adsorbed in the oxide layer, which makes the surface cleanliness higher, thereby improving the battery conversion efficiency.
[0032] In a preferred embodiment, the tunnel oxide layer includes but is not limited to silicon dioxide.
[0033] In the present invention, the thickness of the tunnel oxide layer can be 0.5nm to 2nm, for example, 0.5nm, 0.6nm, 0.7nm, 0.8nm, 0.9nm, 1nm, 1.2nm, 1.4nm, 1.6nm, 1.8nm, 2nm, which is more conducive to ensuring the passivation effect and improving the battery conversion efficiency.
[0034] In a preferred embodiment, the method for growing a tunneling oxide layer includes, but is not limited to, a thermal oxidation method. The thermal oxidation method (Thermal SiOx) uses O2 and N2 atmosphere at high temperature to prepare a tunneling oxide layer, which has a lower interface state density and a better passivation effect than an oxide layer (SiOx) prepared by a plasma assisted nitrous oxide gas oxidation (PANO) method.
[0035] In a preferred embodiment, the tunneling oxide layer is prepared by the LPCVD thermal oxidation method alone, which can not only monitor the thickness, uniformity and density of the tunneling oxide layer for each batch, each tube and each piece, but also make corresponding adjustments to the front and rear production lines, which is conducive to preparing a tunneling oxide layer with better passivation effect, higher uniformity and better matching to the production line, and effectively solves the problem that the film quality of the tunneling oxide layer cannot be effectively monitored in the prior art.
[0036] In a preferred embodiment, the temperature of the thermal oxidation method can be 600-800°C, for example, 600°C, 650°C, 700°C, 750°C or 800°C, and the oxidizing gas used includes, but is not limited to, O2, which is more conducive to obtaining a tunneling oxide layer with higher uniformity and better density.
[0037] In a preferred embodiment, the method for repairing treatment includes the following steps:
[0038] After the tunneling oxide layer is grown on the battery piece (silicon substrate), H2 is introduced to repair the tunneling oxide layer, and then N2 is introduced to repair the tunneling oxide layer.
[0039] In a preferred embodiment, the flow rate of H2 introduced can be 8-11 slm, for example, 8 slm, 9 slm, 10 slm or 11 slm, but is not limited thereto; and the corresponding reaction time can be 1-5 min, for example, 1 min, 2 min, 3 min, 4 min or 5 min, but is not limited thereto.
[0040] The appropriate flow rate of H2 and the reaction time thereof are more conducive to ensuring that the tunneling oxide layer is sufficiently repaired, which can effectively improve the density and uniformity of the oxide layer; if the flow rate of H2 introduced is too large, not only will H2 be wasted, but also the required reaction temperature will be too high, which will cause a mismatch with the original oxide layer growth process; if the flow rate of H2 introduced is too small, part of the surface of the silicon piece will not participate in the reaction, which will not achieve the desired repair effect.
[0041] In a preferred embodiment, the flow rate of the N2 can be 3slm-6slm, for example, can be 3slm, 4slm, 5slm, 6slm, but not limited to; the corresponding reaction time can be 3min-6min, for example, can be 3min, 4min, 5min, 6min, but not limited to.
[0042] The appropriate flow rate of N2 and its reaction time are more conducive to improving the effect of repairing the tunneling oxide layer; if the flow rate of the N2 is too large, not only will it cause waste of N2, but also will lead to too high a degree of bending of the silicon wafer, which is easy to break; if the flow rate of the N2 is too small, because part of the reactants and impurities still remain on the surface of the silicon wafer after the H2 combines with the impurities in the oxide layer, the N2 flow rate that is too small will lead to insufficient removal of the reactants and impurities.
[0043] In summary, under the synergistic cooperation of the steps and the process parameters, the preparation method of the present application can not only effectively monitor the film quality of the tunneling oxide layer, but also is conducive to growing a tunneling oxide layer with a more matched thickness, higher density and better uniformity, can effectively improve the passivation effect, reduce the Si / SiOx interface carrier recombination, and at the same time can remove the adsorbed impurity particles in the oxide layer, which is conducive to providing a good carrier tunneling channel, thereby improving the battery conversion efficiency.
[0044] According to a second aspect of the present application, a Topcon battery prepared by the preparation method of any one of the above is provided.
[0045] The Topcon battery provided by the present application has better passivation effect and higher battery conversion efficiency.
[0046] A typical preparation method of a Topcon battery, comprising the following steps:
[0047] Step 1: selecting an N-type crystalline silicon substrate to sequentially perform the steps of texturing, first boron diffusion, SE, second boron diffusion, BSG removal and alkali etching cleaning to obtain a pretreated battery wafer;
[0048] The resistivity of the N-type crystalline silicon substrate is 0.5Ω·cm-5Ω·cm, and the thickness is 80um-200um;
[0049] The boron source used for boron diffusion is boron tribromide or boron trichloride;
[0050] The first boron diffusion temperature is 800℃-950℃, the time is 1h-2h, and the square resistance value is 100Ω / sqr-140Ω / sqr;
[0051] The second boron diffusion temperature is 900℃-1100℃, the time is 2h-3h, and the square resistance value is 190Ω / sqr-250Ω / sqr;
[0052] Step 2: The pretreated battery piece grows a silicon dioxide film as a tunneling oxide layer by a thermal oxidation method, the reaction temperature of the thermal oxidation method is 600-800℃, vacuum is extracted before the reaction, O2 is introduced during the reaction, and vacuum is extracted after the reaction, and the reaction time is 10-15min;
[0053] The thermal oxidation method uses an LPCVD machine, an annealing machine, an oxidation machine, or a diffusion machine;
[0054] Then, H2 is introduced to repair the tunneling oxide layer, as shown in Figure 1 The reaction temperature is 600-800℃, the H2 flow rate is 8-11slm, and the reaction time is 1-5min, and vacuum is extracted after the reaction;
[0055] Then, N2 is introduced to repair the tunneling oxide layer, as shown in Figure 1 The reaction temperature is 600-800℃, the N2 flow rate is 3-6slm, and the reaction time is 3-6min, and vacuum is extracted after the reaction;
[0056] Step 3: The thickness and uniformity of the tunneling oxide layer in step 2 are monitored by a full-spectrum ellipsometer, one piece is taken from each tube, and 5-9 points are tested for each piece, and the thickness of the tunneling oxide layer can be 0.5-2nm;
[0057] Step 4: The battery piece after the repair treatment in step 2 is deposited with amorphous silicon by a PECVD method, and PH3 gas is introduced for in-situ doping;
[0058] The deposition temperature of the amorphous silicon is 400-500℃, and the deposition thickness is 100-200nm;
[0059] The phosphorus doping concentration is E+20cm -3 order of magnitude;
[0060] Step 5: The battery piece after step 4 is treated by annealing, and the sheet resistance after annealing is 30-50Ω / sqr;
[0061] The annealing temperature is 890-950℃, and the annealing time is 2-3h;
[0062] Step 6: The battery piece after the annealing treatment in step 5 is surface passivated and then metallized to obtain a Topcon battery;
[0063] The front passivation anti-reflective film of the Topcon battery is SiNx, and the back passivation film is SiNx;
[0064] The front passivation anti-reflection film has a thickness of 60-100 nm, and the back passivation film has a thickness of 70-120 nm.
[0065] In summary, in the cooperation of the steps and the process parameters, the Topcon structure battery prepared by the application has a tunneling oxide layer thickness of 0.5-2.0 nm, a within-battery uniformity of <5%, a between-battery uniformity of <5%, a between-batch uniformity of <5%, an open-circuit voltage (Voc) 5 mv higher than that of the prior art, a battery conversion efficiency 0.35% higher than that of the prior art, and an efficiency grade standard deviation 0.4 lower than that of the prior art.
[0066] The application will be further described by examples. Unless otherwise specified, the materials in the examples are prepared according to the prior art method or directly purchased from the market.
[0067] Example 1
[0068] A preparation method of a Topcon battery, comprising the following steps:
[0069] Step 1: selecting an N-type crystalline silicon substrate to sequentially perform the steps of texturing, primary boron diffusion, SE, secondary boron diffusion, BSG removal and alkali cleaning to obtain a pretreated battery;
[0070] The N-type crystalline silicon substrate has a resistivity of 3 Ω·cm and a thickness of 140 um.
[0071] The boron source used for boron diffusion is boron tribromide or boron trichloride.
[0072] The primary boron diffusion temperature is 900℃, the time is 1-2 h, and the square resistance value is 120 Ω / sqr.
[0073] The secondary boron diffusion temperature is 1000℃, the time is 2-3 h, and the square resistance value is 220 Ω / sqr.
[0074] Step 2: the pretreated battery is grown with a silicon dioxide film as a tunneling oxide layer by an LPCVD thermal oxidation method, the reaction temperature of the thermal oxidation method is 700℃, vacuum is extracted before the reaction, O2 is introduced during the reaction, the O2 flow rate is 40 slm, vacuum is extracted again after the reaction, and the reaction time is 13 min.
[0075] Then, H2 is introduced to repair the tunneling oxide layer, the reaction temperature is 700℃, the H2 flow rate is 9.5 slm, the reaction time is 3 min, and vacuum is extracted after the reaction.
[0076] Then, N2 is introduced to repair the tunneling oxide layer, the reaction temperature is 700℃, the N2 flow rate is 4.5 slm, the reaction time is 4.5 min, and vacuum is extracted after the reaction.
[0077] Step 3: The thickness and uniformity of the tunneling oxide layer in step 2 are monitored by a full-spectrum ellipsometer, and each tube is taken out for testing at 5-9 points. The thickness of the tunneling oxide layer is 1.4 nm;
[0078] Step 4: The battery piece after the repair treatment in step 2 is deposited with amorphous silicon by PECVD method, and in-situ doped with PH3 gas;
[0079] The deposition temperature of the amorphous silicon is 450℃, and the deposition thickness is 150 nm.
[0080] The phosphorus doping concentration is E+20cm -3 order of magnitude.
[0081] Step 5: The battery piece after step 4 is annealed, and the sheet resistance after annealing is 40Ω / sqr.
[0082] The annealing temperature is 890℃-950℃, and the annealing time is 2h-3h.
[0083] Step 6: The battery piece after step 5 is surface passivated and then metallized to obtain a Topcon battery.
[0084] The front passivation anti-reflection film of the Topcon battery is SiNx, and the back passivation film is SiNx.
[0085] The thickness of the front passivation anti-reflection film is 80 nm, and the thickness of the back passivation film is 100 nm.
[0086] Example 2
[0087] The difference between this embodiment and Example 1 is that in step 2, the reaction temperature when H2 is introduced for repair treatment is 600℃.
[0088] The remaining steps and their process parameters are the same as those in Example 1, and a Topcon battery is obtained.
[0089] Example 3
[0090] The difference between this embodiment and Example 1 is that in step 2, the reaction temperature when H2 is introduced for repair treatment is 800℃.
[0091] The remaining steps and their process parameters are the same as those in Example 1, and a Topcon battery is obtained.
[0092] Example 4
[0093] The difference between this embodiment and Example 1 is that in step 2, the flow rate of H2 introduced is 8 slm, and the reaction time is 5 min.
[0094] The remaining steps and their process parameters are the same as in Example 1, and a Topcon cell is obtained.
[0095] Example 5
[0096] This example provides a method for preparing a Topcon cell, which differs from Example 1 in that in step 2, the flow rate of H2inlet is 11 slm, and the reaction time is 1 min.
[0097] The remaining steps and their process parameters are the same as in Example 1, and a Topcon cell is obtained.
[0098] Example 6
[0099] This example provides a method for preparing a Topcon cell, which differs from Example 1 in that in step 2, the reaction temperature when N2is introduced for repair treatment is 600°C.
[0100] The remaining steps and their process parameters are the same as in Example 1, and a Topcon cell is obtained.
[0101] Example 7
[0102] This example provides a method for preparing a Topcon cell, which differs from Example 1 in that in step 2, the reaction temperature when N2is introduced for repair treatment is 800°C.
[0103] The remaining steps and their process parameters are the same as in Example 1, and a Topcon cell is obtained.
[0104] Example 8
[0105] This example provides a method for preparing a Topcon cell, which differs from Example 1 in that in step 2, the flow rate of N2inlet is 3 slm, and the reaction time is 6 min.
[0106] The remaining steps and their process parameters are the same as in Example 1, and a Topcon cell is obtained.
[0107] Example 9
[0108] This example provides a method for preparing a Topcon cell, which differs from Example 1 in that in step 2, the flow rate of N2inlet is 6 slm, and the reaction time is 3 min.
[0109] The remaining steps and their process parameters are the same as in Example 1, and a Topcon cell is obtained.
[0110] Example 10
[0111] The embodiment provides a preparation method of a Topcon battery, which is different from the embodiment 1 in that, in step 2, N2 is first introduced to repair the tunneling oxide layer, and then H2 is introduced to repair the tunneling oxide layer.
[0112] The remaining steps and process parameters are the same as those in the embodiment 1, and a Topcon battery is obtained.
[0113] Compared with the embodiment 1, the defect of the embodiment is that the reactants and impurities cannot be removed sufficiently.
[0114] Comparative example 1
[0115] The comparative example provides a preparation method of a Topcon battery, which is different from the embodiment 1 in that, in step 2, H2 and N2 are not introduced to repair the tunneling oxide layer.
[0116] The remaining steps and process parameters are the same as those in the embodiment 1, and a Topcon battery is obtained.
[0117] Compared with the embodiment 1, the defect of the Topcon battery obtained in the comparative example is that not only the tunneling oxide layer surface is loose and weak, but also there are contaminant particles.
[0118] Comparative example 2
[0119] The comparative example provides a preparation method of a Topcon battery, which is different from the embodiment 1 in that, in step 2, only H2 is introduced to repair the tunneling oxide layer.
[0120] The remaining steps and process parameters are the same as those in the embodiment 1, and a Topcon battery is obtained.
[0121] Compared with the embodiment 1, the defect of the Topcon battery obtained in the comparative example is that part of the reactants and impurities still remain on the silicon wafer surface.
[0122] Comparative example 3
[0123] The comparative example provides a preparation method of a Topcon battery, which is different from the embodiment 1 in that, in step 2, only N2 is introduced to repair the tunneling oxide layer.
[0124] The remaining steps and process parameters are the same as those in the embodiment 1, and a Topcon battery is obtained.
[0125] Compared with the embodiment 1, the defect of the Topcon battery obtained in the comparative example is that the purposes of repairing the oxide layer, reacting with the impurities and passivating the surface dangling bonds of the oxide layer by H cannot be achieved.
[0126] Comparative example 4
[0127] The present comparative example provides a preparation method of a Topcon cell, which is different from example 1 in that, in step 2, the reaction temperature is 550°C when H2is introduced to repair the tunneling oxide layer.
[0128] The remaining steps and their process parameters are the same as those in example 1, and a Topcon cell is obtained.
[0129] Compared with example 1, the defect of the Topcon cell obtained in the present comparative example is that the repair reaction is insufficient, and it is difficult to effectively improve the density and uniformity of the oxide layer.
[0130] Comparative example 5
[0131] The present comparative example provides a preparation method of a Topcon cell, which is different from example 1 in that, in step 2, the reaction temperature is 850°C when H2is introduced to repair the tunneling oxide layer.
[0132] The remaining steps and their process parameters are the same as those in example 1, and a Topcon cell is obtained.
[0133] Compared with example 1, the defect of the Topcon cell obtained in the present comparative example is that the repair reaction is too violent, the density is too high, and the uniformity is instead poor.
[0134] Comparative example 6
[0135] The present comparative example provides a preparation method of a Topcon cell, which is different from example 1 in that, in step 2, the reaction temperature is 550°C when N2is introduced to repair the tunneling oxide layer.
[0136] The remaining steps and their process parameters are the same as those in example 1, and a Topcon cell is obtained.
[0137] Compared with example 1, the defect of the Topcon cell obtained in the present comparative example is that the activity of the reactants and impurities is reduced at low temperature, which makes it difficult to be removed.
[0138] Comparative example 7
[0139] The present comparative example provides a preparation method of a Topcon cell, which is different from example 1 in that, in step 2, the reaction temperature is 850°C when N2is introduced to repair the tunneling oxide layer.
[0140] The remaining steps and their process parameters are the same as those in example 1, and a Topcon cell is obtained.
[0141] Compared with example 1, the defect of the Topcon cell obtained in the present comparative example is that the reactants and impurities will further enter the inside of the silicon wafer at high temperature, which makes it difficult to be removed.
[0142] Test Example
[0143] The Topcon cells obtained from the Examples and the Comparative Examples were tested according to the test items in Table 1, and the test results are shown in Table 1.
[0144] The test method is as follows:
[0145] Compactness: the thickness growth value of the oxide layer after standing for 3 hours after LPCVD is used as an indicator;
[0146] Uniformity: the thickness after LPCVD is measured by a full-spectrum ellipsometer, and is calculated by (max-min) / 2avg;
[0147] Surface cleanliness: ivoc is used as an indicator after LPCVD;
[0148] Conversion efficiency: the finished cell is tested by halm.
[0149] Table 1
[0150]
[0151] As shown in Table 1, when the LPCVD thermal oxidation method is used to deposit and grow the tunnel oxide layer, not only will there be loose and weak places on the surface of the oxide layer, but there will also be contaminant particles in the oxide layer, which come from the impurity particles adsorbed on the surface of the silicon wafer before entering the furnace tube, from the environmental impurity particles originally present in the furnace tube, quartz boat, boat holder and paddle, and from the environmental impurity particles outside the furnace tube during oxidation, which will cause poor passivation effect and lead to reduced conversion efficiency of the cell; after the LPCVD thermal oxidation method is used to grow the tunnel oxide layer in the present application, H2 and N2 are introduced to repair the loose and weak places of the oxide layer, and the hydrogen passivates the dangling bonds on the surface of the oxide layer, which can make the oxide layer more compact and uniform, can effectively improve the passivation effect, and can also remove the contaminant particles adsorbed in the oxide layer, so that the surface cleanliness of the silicon wafer is higher, thereby improving the conversion efficiency of the cell.
[0152] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.
Claims
1. A method of fabricating a Topcon cell tunnel oxide layer, characterized by, The method comprises the following steps: After the growth of the battery piece through the tunneling oxide layer, the tunneling oxide layer is repaired by H2 and N2 to obtain a repaired tunneling oxide layer; The repairing temperature is 600-800℃.
2. The production method according to claim 1, characterized by, The tunneling oxide layer comprises silicon dioxide.
3. The production method according to claim 2, characterized by, The thickness of the tunneling oxide layer is 0.5-2nm.
4. The production method according to any one of claims 1 to 3, characterized by, The method for growing the tunneling oxide layer comprises a thermal oxidation method; Preferably, the thermal oxidation method comprises an LPCVD thermal oxidation method.
5. The preparation method according to claim 4, characterized in that The temperature of the thermal oxidation method is 600-800℃. Preferably, the oxidation gas used in the thermal oxidation method comprises O2.
6. The method of any one of claims 1-3, wherein, The repairing method comprises the following steps: First, H2 is introduced to repair the tunneling oxide layer, and then N2 is introduced to repair the tunneling oxide layer.
7. The production method according to claim 6, characterized by, The flow rate of H2 is 8-11slm, and the reaction time is 1-5min.
8. The preparation method according to claim 6, characterized in that The flow rate of N2 is 3-6slm, and the reaction time is 3-6min.
9. A Topcon battery prepared by the preparation method of any one of claims 1-8.
10. The Topcon cell of claim 9, wherein, The conversion efficiency of the Topcon battery is 26.50-26.60%.