Passivation method of aluminum boat, aluminum boat and passivation method of battery piece pre-finished product
By preheating the aluminum boat at a constant temperature and passing through cycle, a uniform and dense aluminum oxide protective layer is formed, which solves the problem of black edge defects caused by aluminum boats in the ALD process and improves the efficiency and yield of solar cells.
Patent Information
- Application Number
- CN202310773095.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-06-28
- Publication Date
- 2024-12-31
AI Technical Summary
In the ALD process of solar cells, traditional aluminum boats can easily lead to black edge defects on the surface of the cell, affecting the efficiency and yield of the cell.
After constant temperature preheating treatment of the aluminum boat, multiple passivation treatments are performed in cycles, including pretreatment in the gaseous trimethylaluminum gas atmosphere and passivation in the ozone gas atmosphere to form a uniform and dense aluminum oxide protective layer to reduce black Edge defects.
The efficiency and yield of solar cell are improved, the black edge defects formed by the aluminum boat on the surface of the cell are reduced, and the density and film formation of the alumina protective layer are enhanced.
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Figure CN119220972A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of solar cells, and in particular to a passivation method for an aluminum boat, an aluminum boat, and a passivation method for a pre-finished solar cell product. Background Art
[0002] The conventional process route of crystalline silicon solar cells is texturing → diffusion → etching → oxidation → plasma enhanced chemical vapor deposition (PECVD) → screen printing. With the demand for high conversion efficiency solar cells, the conventional process route of crystalline silicon solar cells can no longer meet the demand. In order to improve the conversion efficiency of crystalline silicon solar cells, PERC cell (Passivated Emitter and Rear Cell) technology is an innovative technology for P-type solar cells. The process route of this technology is texturing → diffusion → front emitter improvement (SE) → oxidation → alkaline polishing → annealing → atomic layer deposition (ALD) → front PECVD → back PECVD → screen printing. The biggest difference between PERC cells and conventional cells is the passivation of the back surface dielectric film, that is, the addition of ALD atomic layer deposition, and the use of laser etching to achieve local metal contact when the cell is screen printed, thereby reducing the recombination rate of the back surface and improving the reflection of the back surface.
[0003] When performing the ALD process on the cell, the use of traditional aluminum boats is prone to forming black edge defects on the surface of the cell, which in turn causes poor electroluminescence (EL) testing of the cell, affecting the efficiency and yield of the cell. Summary of the invention
[0004] Based on this, it is necessary to provide a passivation method for an aluminum boat, an aluminum boat, and a passivation method for a pre-finished battery cell. When the aluminum boat treated by the passivation method is used in the ALD process of a battery cell, the black edge defect formed by the aluminum boat on the surface of the battery cell can be reduced, thereby improving the efficiency and yield rate of the battery cell.
[0005] In a first aspect, the present application provides a passivation method for an aluminum boat, comprising:
[0006] The aluminum boat is subjected to constant temperature preheating treatment;
[0007] Performing multiple passivation treatments on the aluminum boat after the constant temperature preheating treatment;
[0008] The passivation treatment comprises: pre-treating the aluminum boat after the constant temperature preheating treatment in a gaseous trimethylaluminum atmosphere, and then passivating the pre-treated aluminum boat in an ozone gas atmosphere.
[0009] In some embodiments, the temperature of the constant temperature preheating treatment is 235°C~250°C.
[0010] In some embodiments, the constant temperature preheating treatment lasts for 700s to 1500s.
[0011] In some embodiments, in a single passivation treatment, the pretreatment time is 1000ms~5000ms.
[0012] In some embodiments, during a single passivation treatment, the gas pressure of the gaseous trimethylaluminum atmosphere is 20 Torr to 35 Torr.
[0013] In some embodiments, in a single passivation treatment, the time for passivating the pre-treated aluminum boat in an ozone gas atmosphere is 2000ms to 8000ms.
[0014] In some embodiments, in a single passivation treatment, the flow rate of the ozone is 2000 sccm to 7000 sccm.
[0015] In some embodiments, before passivating the pre-treated aluminum boat in an ozone gas atmosphere, the method further includes: purging the gaseous trimethylaluminum with nitrogen.
[0016] In some embodiments, after passivating the pre-treated aluminum boat in an ozone gas atmosphere, the method further includes: purging the ozone with nitrogen.
[0017] In some embodiments, the time for purging the gaseous trimethylaluminum with nitrogen is 2000 ms to 5000 ms.
[0018] In some embodiments, the nitrogen flow rate of the nitrogen used to purge the gaseous trimethylaluminum is 2000 sccm-10000 sccm.
[0019] In some embodiments, the time for purging the ozone with nitrogen is 3000 ms to 10000 ms.
[0020] In some embodiments, the flow rate of the nitrogen gas used to purge the ozone is 5000 sccm-10000 sccm.
[0021] In some embodiments, the multiple passivation treatments are performed 50 to 200 times.
[0022] In a second aspect, the present application provides an aluminum boat obtained by processing using any of the above-mentioned passivation methods for the aluminum boat.
[0023] In a third aspect, the present application provides a method for passivating a pre-finished battery cell, comprising:
[0024] Provide pre-finished battery cells;
[0025] Passivating the aluminum boat using any of the above-mentioned passivation methods for an aluminum boat;
[0026] The passivated aluminum boat is used to receive the battery cell pre-finished product, and the battery cell pre-finished product is passivated.
[0027] The above-mentioned aluminum boat passivation method can form a uniform and dense aluminum oxide protective layer on the surface of the aluminum boat by cyclically performing multiple passivation treatments on the aluminum boat after constant temperature preheating treatment, and the passivation treatment includes pretreatment in a gaseous trimethylaluminum gas atmosphere and passivation in an ozone gas atmosphere. When the aluminum boat passivated by the passivation method is used in the ALD process of the battery cell, the black edge defect formed by the aluminum boat on the surface of the battery cell can be reduced, thereby improving the efficiency and yield rate of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS
[0028] Figure 1 A schematic flow chart of a passivation method for an aluminum boat provided in one embodiment of the present application;
[0029] Figure 2 A schematic flow chart of a method for passivating an aluminum boat provided in yet another embodiment of the present application;
[0030] Figure 3 A schematic diagram of the surface of a battery cell contaminated by the black edge of an aluminum boat provided in this application;
[0031] Figure 4 A schematic diagram of the surface of a battery cell without black edge contamination of an aluminum boat provided in an embodiment of the present application. DETAILED DESCRIPTION
[0032] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.
[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.
[0034] Reference Figure 3 When untreated aluminum boats are used in the ALD process in the production of solar cells, they can easily cause black edge contamination to the cells.
[0035] Reference Figure 1 , an embodiment of the present application provides a passivation method for an aluminum boat, comprising:
[0036] S10: performing constant temperature preheating treatment on the aluminum boat;
[0037] S20: performing multiple passivation treatments on the aluminum boat after the constant temperature preheating treatment; the passivation treatment includes: pretreating the aluminum boat after the constant temperature preheating treatment in a gaseous trimethylaluminum atmosphere, and then passivating the pretreated aluminum boat in an ozone gas atmosphere.
[0038] It can be understood that the above-mentioned method of treating the aluminum boat is to place the aluminum boat in a reaction container for treatment.
[0039] The above-mentioned passivation method of the aluminum boat is to perform multiple passivation treatments on the aluminum boat after constant temperature preheating treatment in a cycle, and the passivation treatment includes pretreatment in a gaseous trimethylaluminum atmosphere and passivation in an ozone gas atmosphere, so that a uniform and dense aluminum oxide protective layer can be formed on the surface of the aluminum boat, and the passivation treatment is a multiple-cycle passivation process, and the density and film-forming property of the aluminum oxide protective layer are good. When the aluminum boat treated by the treatment method is used in the ALD process of the battery cell, the black edge defect formed by the aluminum boat on the surface of the battery cell can be reduced, thereby improving the efficiency and yield rate of the battery cell.
[0040] In some embodiments, the temperature of the constant temperature preheating treatment is 235°C to 250°C. Within the temperature range of the constant temperature preheating treatment, the treatment effect on the aluminum boat in the passivation treatment is better, and the formation of the aluminum oxide protective layer can be more uniform. When the temperature of the constant temperature preheating treatment is too low, the activity of the gas molecules will be insufficient, resulting in poor density of the aluminum oxide film layer; when the temperature of the constant temperature preheating treatment is too high, the introduction of ozone will cause ozone to decompose too quickly, resulting in poor passivation effect of the aluminum oxide film layer. Optionally, the temperature of the constant temperature preheating treatment is 235°C, 236°C, 237°C, 238°C, 239°C, 240°C, 241°C, 242°C, 243°C, 244°C, 245°C, 246°C, 247°C, 248°C, 249°C or 250°C.
[0041] In some embodiments, the constant temperature preheating treatment lasts for 700s to 1500s. Within the time range of the constant temperature preheating treatment, the effect of the constant temperature preheating treatment is better, the treatment effect of the aluminum boat in the passivation treatment is better, and the formation of the aluminum oxide protective layer can be more uniform. Optionally, the constant temperature preheating treatment lasts for 700s, 750s, 800s, 850s, 900s, 950s, 1000s, 1050s, 1100s, 1150s, 1200s, 1250s, 1300s, 1350s, 1400s, 1450s or 1500s.
[0042] In some embodiments, in a single passivation treatment, the pretreatment time is 1000ms to 5000ms. Within the pretreatment time range in the single passivation treatment, the pretreatment effect is good, the passivation effect on the aluminum boat is good, and the formation of the aluminum oxide protective layer can be more uniform. Optionally, in a single passivation treatment, the pretreatment time is 1000ms, 1100ms, 1200ms, 1300ms, 1400ms, 1500ms, 1600ms, 1700ms, 1800ms, 1900ms, 2000ms, 2100ms, 2200ms, 2300ms, 2400ms, 2500ms, 2600ms, 2700ms, 2800ms, 2900ms, 3000ms, 3100ms, 3200ms, 3300ms, 3400ms, 3500ms, 3600ms, 3700ms, 3800ms, 3900ms, 4000ms, 4100ms, 4200ms, 4300ms, 4400ms, 4500ms, 4600ms, 4700ms, 4800ms, 4900ms, 5000ms, 5100ms, 5200ms, 5300ms, 5400ms, 5500ms, 5600ms, 5700ms, 5800ms, 5900ms, 6000ms, 6100ms, 6200ms, 6300ms, 6400ms, 6500ms, 6600ms, 6700ms, 6800ms, 690 900ms, 3000ms, 3100ms, 3200ms, 3300ms, 3400ms, 3500ms, 3600ms, 3700ms, 3800ms, 3900ms, 4000ms, 4100ms, 4200ms, 4300ms, 4400ms, 4500ms, 4600ms, 4700ms, 4800ms, 4900ms or 5000ms.
[0043] In some embodiments, in a single passivation treatment, the gas pressure of the gaseous trimethylaluminum gas atmosphere is 20 Torr to 35 Torr. When the gas pressure of the gaseous trimethylaluminum gas atmosphere is too high, it will cause waste of raw materials. When the gas pressure of the gaseous trimethylaluminum gas atmosphere is too low, it will cause poor film formation uniformity of the aluminum oxide film layer. Optionally, the gas pressure of the gaseous trimethylaluminum gas atmosphere is 20 Torr, 21 Torr, 22 Torr, 23 Torr, 24 Torr, 25 Torr, 26 Torr, 27 Torr, 28 Torr, 29 Torr, 30 Torr, 31 Torr, 32 Torr, 33 Torr, 34 Torr or 35 Torr.
[0044] In some embodiments, in a single passivation treatment, the pretreated aluminum boat is passivated in an ozone atmosphere for a period of 2000ms to 8000ms. Within the time range of the pretreated aluminum boat being passivated in an ozone atmosphere in the single passivation treatment, the passivation effect is better, and the treatment effect of the aluminum boat in the passivation treatment is better, which can make the formation of the aluminum oxide protective layer more uniform. Optionally, in a single passivation treatment, the pretreated aluminum boat is passivated in an ozone gas atmosphere for a time period of 2000ms, 2200ms, 2500ms, 2800ms, 3000ms, 3200ms, 3500ms, 3800ms, 4000ms, 4200ms, 4500ms, 4800ms, 5000ms, 5200ms, 5500ms, 5800ms, 6000ms, 6200ms, 6500ms, 6800ms, 7000ms, 7200ms, 7500ms, 7800ms or 8000ms.
[0045] In some embodiments, in a single passivation treatment, the ozone flow rate is 2000 sccm to 7000 sccm. Within this ozone flow rate range, the passivation effect is better, the passivation treatment effect on the aluminum boat is better, and the aluminum oxide protective layer can be formed more uniformly. Optionally, the flow rate of ozone is 2000sccm, 2200sccm, 2400sccm, 2600sccm, 2800sccm, 3000sccm, 3200sccm, 3400sccm, 3600sccm, 3800sccm, 4000sccm, 4200sccm, 4400sccm, 4600sccm, 4800sccm, 5000sccm, 5200sccm, 5400sccm, 5600sccm, 5800sccm, 6000sccm, 6200sccm, 6400sccm, 6600sccm, 6800sccm or 7000sccm.
[0046] In some embodiments, before the pretreated aluminum boat is passivated in an ozone gas atmosphere, the process further includes: purging the gaseous trimethylaluminum with nitrogen. Purging the gaseous trimethylaluminum with nitrogen can reduce reaction byproducts. The nitrogen used in all embodiments of the present application is high-purity nitrogen, i.e., nitrogen with a purity of more than 99.999%, to prevent the introduction of impurities and improve the quality and stability of the aluminum oxide film preparation.
[0047] In some embodiments, the time for purging gaseous trimethylaluminum with nitrogen is 2000ms to 5000ms. Within the time range for purging gaseous trimethylaluminum with nitrogen, the effect of purging gaseous trimethylaluminum with nitrogen is better, and the residual gaseous trimethylaluminum can be reduced. Optionally, the time for purging gaseous trimethylaluminum with nitrogen is 2000ms, 2200ms, 2400ms, 2600ms, 2800ms, 3000ms, 3200ms, 3400ms, 3600ms, 3800ms, 4000ms, 4200ms, 4400ms, 4600ms, 4800ms or 5000ms.
[0048] In some embodiments, gaseous trimethylaluminum is introduced into the reaction vessel via a gaseous trimethylaluminum line.
[0049] In some embodiments, ozone is introduced into the reaction vessel via an ozone line.
[0050] In some embodiments, gaseous trimethylaluminum is obtained by volatilizing liquid trimethylaluminum.
[0051] In some embodiments, the gas pressure of the gaseous trimethylaluminum atmosphere is controlled by controlling the volatilization amount of liquid trimethylaluminum.
[0052] In some embodiments, the volatilization amount of liquid trimethylaluminum is controlled by controlling the temperature of the source bottle of liquid trimethylaluminum.
[0053] In some embodiments, the temperature of the source bottle of liquid trimethylaluminum is 45° C. to 55° C. Optionally, the temperature of the source bottle of liquid trimethylaluminum is 45° C., 46° C., 47° C., 48° C., 49° C., 50° C., 51° C., 52° C., 53° C., 54° C. or 55° C.
[0054] In some embodiments, the flow rate of nitrogen used to purge gaseous trimethylaluminum is 2000sccm to 10000sccm. Within the flow rate range of nitrogen used to purge gaseous trimethylaluminum, the effect of nitrogen purging gaseous trimethylaluminum is better, and the residual gaseous trimethylaluminum can be reduced. Optionally, the flow rate of nitrogen used to purge gaseous trimethylaluminum is 2000sccm, 2500sccm, 3000sccm, 3500sccm, 4000sccm, 4500sccm, 5000sccm, 5500sccm, 6000sccm, 6500sccm, 7000sccm, 7500sccm, 8000sccm, 8500sccm, 9000sccm, 9500sccm or 10000sccm.
[0055] In some embodiments, after purging the gaseous trimethylaluminum with nitrogen and before passivating the pretreated aluminum boat in an ozone gas atmosphere, the method further includes: performing a first pipeline purge on the gaseous trimethylaluminum pipeline and the ozone pipeline with nitrogen. The first pipeline purge on the gaseous trimethylaluminum pipeline and the ozone pipeline with nitrogen can clean the pollutants in the pipelines.
[0056] In some embodiments, the time for the first pipeline purge of the gaseous trimethylaluminum pipeline and the ozone pipeline using nitrogen is 5000ms to 10000ms. Within the time range of the first pipeline purge, the first pipeline purge of the gaseous trimethylaluminum pipeline and the ozone pipeline using nitrogen has a better effect of cleaning the pollutants in the pipeline. Optionally, the time for the first pipeline purge of the gaseous trimethylaluminum pipeline and the ozone pipeline using nitrogen is 5000ms, 5200ms, 5400ms, 5600ms, 5800ms, 6000ms, 6200ms, 6400ms, 6600ms, 6800ms, 7000ms, 7200ms, 7400ms, 7600ms, 7800ms, 80000ms, 8200ms, 8400ms, 8600ms, 8800ms, 9000ms, 9200ms, 9400ms, 9600ms, 9800ms or 10000ms.
[0057] In some embodiments, the flow rate of nitrogen used to perform the first pipeline purge on the gaseous trimethylaluminum pipeline and the ozone pipeline is 5000 sccm to 10000 sccm. Within the flow rate range of the nitrogen used for the first pipeline purge, the effect of using nitrogen to perform the first pipeline purge on the gaseous trimethylaluminum pipeline and the ozone pipeline to clean the pollutants in the pipeline is better. Optionally, the flow rate of nitrogen used for the first pipeline purge of the gaseous trimethylaluminum pipeline and the ozone pipeline is 5000sccm, 5200sccm, 5400sccm, 5600sccm, 5800sccm, 6000sccm, 6200sccm, 6400sccm, 6600sccm, 6800sccm, 7000sccm, 7200sccm, 7400sccm, 7600sccm, 7800sccm, 80000sccm, 8200sccm, 8400sccm, 8600sccm, 8800sccm, 9000sccm, 9200sccm, 9400sccm, 9600sccm, 9800sccm or 10000sccm.
[0058] In some embodiments, after the gaseous trimethylaluminum pipeline and the ozone pipeline are first purged with nitrogen and before the pre-treated aluminum boat is passivated in an ozone gas atmosphere, the process further includes: performing a first vacuuming treatment on the reaction container. The first vacuuming treatment can remove waste gas in the reaction container and prepare for the next gas flow.
[0059] In some embodiments, the time for the first vacuuming treatment of the reaction container is 2000ms to 5000ms. Within the time range of the first vacuuming treatment, the first vacuuming treatment has a better effect of removing waste gas in the reaction container. Optionally, the time for the first vacuuming treatment of the reaction container is 2000ms, 2200ms, 2400ms, 2600ms, 2800ms, 3000ms, 3200ms, 3400ms, 3600ms, 3800ms, 4000ms, 4200ms, 4400ms, 4600ms, 4800ms or 5000ms.
[0060] In some embodiments, after passivating the pretreated aluminum boat in an ozone atmosphere, the method further includes: purging the ozone with nitrogen. Purging the ozone with nitrogen can reduce reaction byproducts.
[0061] In some embodiments, the time for purging ozone with nitrogen is 3000ms to 10000ms. Within the time range for purging ozone with nitrogen, purging ozone with nitrogen has a better effect of reducing reaction byproducts. Optionally, the time for purging ozone with nitrogen is 3000ms, 3500ms, 4000ms, 4500ms, 1000ms, 5500ms, 6000ms, 6500ms, 7000ms, 7500ms, 8000ms, 8500ms, 9000ms, 9500ms or 10000ms.
[0062] In some embodiments, the flow rate of nitrogen used to purge ozone is 5000sccm to 10000sccm. Within the flow rate range of nitrogen used to purge ozone, the purge effect of ozone is better. Optionally, the flow rate of nitrogen used to purge ozone is 5000sccm, 5500sccm, 6000sccm, 6500sccm, 7000sccm, 7500sccm, 8000sccm, 8500sccm, 9000sccm, 9500sccm or 10000sccm.
[0063] In some embodiments, after purging the ozone with nitrogen, the method further includes: performing a second pipeline purge on the gaseous trimethylaluminum pipeline and the ozone pipeline with nitrogen. The second pipeline purge on the gaseous trimethylaluminum pipeline and the ozone pipeline with nitrogen can clean the pollutants in the pipelines.
[0064] In some embodiments, the time for using nitrogen to purge the gaseous trimethylaluminum pipeline and the ozone pipeline for the second pipeline is 3000ms to 10000ms. Within the time range of the second pipeline purge, the effect of using nitrogen to purge the gaseous trimethylaluminum pipeline and the ozone pipeline for the second pipeline to clean the pollutants in the pipeline is better. Optionally, the time for using nitrogen to purge the gaseous trimethylaluminum pipeline and the ozone pipeline for the second pipeline is 3000ms, 3500ms, 4000ms, 4500ms, 5000ms, 5500ms, 6000ms, 6500ms, 7000ms, 7500ms, 8000ms, 8500ms, 9000ms, 9500ms or 10000ms.
[0065] In some embodiments, the flow rate of nitrogen used to purge the gaseous trimethylaluminum pipeline and the ozone pipeline for the second pipeline is 5000sccm to 10000sccm. Within the flow rate range of the nitrogen used to purge the second pipeline, the effect of cleaning the pollutants in the pipeline by using nitrogen to purge the gaseous trimethylaluminum pipeline and the ozone pipeline for the second pipeline is better. Optionally, the flow rate of nitrogen used to purge the gaseous trimethylaluminum pipeline and the ozone pipeline for the second pipeline is 5000sccm, 5500sccm, 6000sccm, 6500sccm, 7000sccm, 7500sccm, 8000sccm, 8500sccm, 9000sccm, 9500sccm or 10000sccm.
[0066] In some embodiments, after using nitrogen to perform a second pipeline purge on the gaseous trimethylaluminum pipeline and the ozone pipeline, it also includes performing a second vacuum treatment on the reaction container. The second vacuum treatment can remove waste gas in the reaction container and prepare for the next gas flow.
[0067] In some embodiments, the time for performing the second vacuum treatment on the reaction container is 2000ms to 5000ms. Within the time range of the second vacuum treatment, the second vacuum treatment has a better effect of removing waste gas in the reaction container. Optionally, the time for performing the second vacuum treatment on the reaction container is 2000ms, 2200ms, 2400ms, 2600ms, 2800ms, 3000ms, 3200ms, 3400ms, 3600ms, 3800ms, 4000ms, 4200ms, 4400ms, 4600ms, 4800ms or 5000ms.
[0068] In some embodiments, the reaction vessel is an ALD apparatus.
[0069] In some embodiments, the number of cycles of the multiple-cycle passivation treatment is 50 to 200. Within the range of the number of cycles of the multiple-cycle passivation treatment, the treatment effect on the aluminum boat in the passivation treatment is better, and the formation of the aluminum oxide protective layer can be more uniform. Optionally, the number of cycles of the multiple-cycle passivation treatment is 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 155, 160, 165, 170, 175, 180, 185, 190, 195 or 200.
[0070] In some embodiments, after multiple passivation treatments, the process further includes: purging the reaction container with nitrogen, evacuating the reaction container, filling the reaction container with nitrogen to return it to normal pressure, and then removing the pressure from the boat.
[0071] In some embodiments, reference Figure 2 , the passivation methods for aluminum boats include:
[0072] S100: performing a constant temperature preheating treatment on the aluminum boat in a reaction container;
[0073] S200: multiple passivation treatments are performed on the aluminum boat after constant temperature preheating treatment;
[0074] S300: After multiple passivation treatments, the reaction container is purged with nitrogen, and then the reaction container is evacuated, and then filled with nitrogen to return the reaction container to normal pressure and the boat is removed;
[0075] Passivation treatment includes:
[0076] S210: pre-treating the aluminum boat after constant temperature preheating in a gaseous trimethylaluminum atmosphere;
[0077] S220: purging gaseous trimethylaluminum with nitrogen;
[0078] S230: using nitrogen to perform a first pipeline purge on the gaseous trimethylaluminum pipeline and the ozone pipeline;
[0079] S240: performing a first vacuuming process on the reaction container;
[0080] S250: passivating the pretreated aluminum boat in an ozone gas atmosphere;
[0081] S260: purge ozone with nitrogen;
[0082] S270: Performing a second pipeline purge on the gaseous trimethylaluminum pipeline and the ozone pipeline using nitrogen;
[0083] S280: performing a second vacuuming process on the reaction container.
[0084] In some embodiments, a method for passivating an aluminum boat comprises the following steps:
[0085] The aluminum boat is subjected to a constant temperature preheating treatment in a reaction container, the temperature of the constant temperature preheating treatment is 235° C. to 250° C., and the time of the constant temperature preheating treatment is 700s to 1500s;
[0086] The aluminum boat after constant temperature preheating treatment is subjected to multiple passivation treatments, the number of times being 50 to 200 times;
[0087] After multiple passivation treatments, the reaction container is purged with nitrogen, and then the reaction container is evacuated, and then filled with nitrogen to return the reaction container to normal pressure and the boat is removed;
[0088] Each passivation treatment includes:
[0089] The aluminum boat after constant temperature preheating is pretreated in a gaseous trimethylaluminum atmosphere for a pretreatment time of 1000ms to 5000ms;
[0090] The gaseous trimethylaluminum is purged with nitrogen for a time of 2000 ms to 5000 ms and a nitrogen flow rate of 2000 sccm to 10000 sccm;
[0091] Use nitrogen to perform a first pipeline purge on the gaseous trimethylaluminum pipeline and the ozone pipeline. The first pipeline purge time is 5000ms~10000ms, and the flow rate of nitrogen is 5000sccm~10000sccm;
[0092] Performing a first vacuuming treatment on the reaction container, wherein the time of the first vacuuming treatment is 2000ms to 5000ms;
[0093] The pretreated aluminum boat is passivated in an ozone gas atmosphere for a time of 2000ms to 8000ms and an ozone flow rate of 2000sccm to 7000sccm;
[0094] Use nitrogen to purge ozone for 3000ms~10000ms, and the flow rate of nitrogen is 5000sccm~10000sccm;
[0095] Use nitrogen to purge the gaseous trimethylaluminum pipeline and the ozone pipeline for the second pipeline, the purge time of the second pipeline is 3000ms~10000ms, and the flow rate of nitrogen is 5000sccm~10000sccm;
[0096] The reaction container is subjected to a second vacuuming treatment, and the time for the second vacuuming treatment is 2000ms~5000ms.
[0097] In some embodiments, the passivation method of the aluminum boat is as follows:
[0098] The aluminum boat is subjected to a constant temperature preheating treatment in a reaction container, the temperature of the constant temperature preheating treatment is 235° C. to 250° C., and the time of the constant temperature preheating treatment is 1000 s to 2000 s;
[0099] The aluminum boat after constant temperature preheating treatment is subjected to multiple passivation treatments, the number of times being 50 to 200 times;
[0100] After multiple cycles of passivation treatment, the reaction container is purged with nitrogen, and then the reaction container is evacuated, and then filled with nitrogen to return the reaction container to normal pressure and the boat is removed;
[0101] The single passivation process is as follows:
[0102] The aluminum boat after constant temperature preheating is pretreated in a gaseous trimethylaluminum atmosphere for a pretreatment time of 1000ms to 5000ms;
[0103] The gaseous trimethylaluminum is purged with nitrogen for a time of 2000 ms to 5000 ms and a nitrogen flow rate of 2000 sccm to 10000 sccm;
[0104] Use nitrogen to perform a first pipeline purge on the gaseous trimethylaluminum pipeline and the ozone pipeline. The first pipeline purge time is 5000ms~10000ms, and the flow rate of nitrogen is 5000sccm~10000sccm;
[0105] Performing a first vacuuming treatment on the reaction container, wherein the time of the first vacuuming treatment is 2000ms to 5000ms;
[0106] The pretreated aluminum boat is passivated in an ozone gas atmosphere for a time of 2000ms to 8000ms and an ozone flow rate of 2000sccm to 7000sccm;
[0107] Use nitrogen to purge ozone for 3000ms~10000ms, and the flow rate of nitrogen is 5000sccm~10000sccm;
[0108] Use nitrogen to purge the gaseous trimethylaluminum pipeline and the ozone pipeline for the second pipeline, the purge time of the second pipeline is 3000ms~10000ms, and the flow rate of nitrogen is 5000sccm~10000sccm;
[0109] The reaction container is subjected to a second vacuuming treatment, and the time for the second vacuuming treatment is 2000ms~5000ms.
[0110] Yet another embodiment of the present application provides an aluminum boat obtained by processing with any of the above-mentioned passivation methods for the aluminum boat.
[0111] The present application further provides a method for passivating a battery cell pre-finished product, comprising: providing a battery cell pre-finished product; passivating the aluminum boat using any of the above-mentioned passivation methods for an aluminum boat; using the passivated aluminum boat to receive the battery cell pre-finished product and passivating the battery cell pre-finished product.
[0112] In some embodiments, the cell pre-product is a PERC solar cell pre-product.
[0113] In some embodiments, the cell pre-product is a PERC solar cell pre-product that has undergone texturing → diffusion → front emitter improvement (SE) → oxidation → alkaline polishing → annealing.
[0114] The passivation method of the aluminum boat provided in the present application can be directly used as a preliminary step for the passivation treatment of the pre-finished battery cells. First, the empty aluminum boat without any battery cells is passivated using ALD equipment. After the passivation of the aluminum boat is completed, the battery cells can be passivated directly using gaseous trimethylaluminum and ozone without changing the gas raw materials. The process has good consistency and high practicality.
[0115] The following are specific embodiments
[0116] Example 1
[0117] Passivation method of aluminum boat:
[0118] (1) The aluminum boat is subjected to a constant temperature preheating treatment in the ALD equipment. The temperature of the constant temperature preheating treatment is 240°C and the time of the constant temperature preheating treatment is 1500 seconds.
[0119] (2) The aluminum boat after constant temperature preheating treatment is subjected to 80 cycles of passivation treatment. The passivation treatment is as follows:
[0120] (2-1) pre-treating the aluminum boat after the constant temperature preheating treatment in a gaseous trimethylaluminum atmosphere for 4000 ms at a gas pressure of 30 Torr;
[0121] (2-2) Using nitrogen to purge the gaseous trimethylaluminum in the ALD equipment for 1500 ms at a nitrogen flow rate of 3000 sccm;
[0122] (2-3) Using nitrogen to perform a first pipeline purge on the gaseous trimethylaluminum pipeline and the ozone pipeline of the ALD equipment, the first pipeline purge time is 10000 ms, and the flow rate of nitrogen is 10000 sccm;
[0123] (2-4) performing a first vacuum pumping process on the ALD equipment, the time of the first vacuum pumping process being 1500 ms;
[0124] (2-5) passivating the pretreated aluminum boat in an ozone gas atmosphere for 6000 ms at an ozone flow rate of 6000 sccm;
[0125] (2-6) Use nitrogen gas to purge the ozone in the ALD equipment for 3000 ms at a nitrogen flow rate of 10000 sccm;
[0126] (2-7) Using nitrogen to perform a second pipeline purge on the gaseous trimethylaluminum pipeline and the ozone pipeline of the ALD equipment, the second pipeline purge time is 3000 ms, and the flow rate of nitrogen is 10000 sccm;
[0127] (2-8) performing a second vacuuming treatment on the reaction container, wherein the time for the second vacuuming treatment is 1000 ms;
[0128] (3) After multiple cycles of passivation treatment, the ALD equipment is purged with nitrogen, and then the ALD equipment is evacuated and filled with nitrogen to return the ALD equipment to normal pressure and then taken out of the boat.
[0129] Example 2
[0130] Passivation method of aluminum boat:
[0131] (1) The aluminum boat is subjected to a constant temperature preheating treatment in the ALD equipment. The temperature of the constant temperature preheating treatment is 240°C and the time of the constant temperature preheating treatment is 1500 seconds.
[0132] (2) The aluminum boat after constant temperature preheating treatment is subjected to 150 cycles of passivation treatment. The passivation treatment is as follows:
[0133] (2-1) pre-treating the aluminum boat after the constant temperature preheating treatment in a gaseous trimethylaluminum atmosphere for 2000 ms at a gas pressure of 30 Torr;
[0134] (2-2) Using nitrogen to purge the gaseous trimethylaluminum in the ALD equipment for 3000 ms at a nitrogen flow rate of 4000 sccm;
[0135] (2-3) Using nitrogen to perform a first pipeline purge on the gaseous trimethylaluminum pipeline and the ozone pipeline of the ALD equipment. The first pipeline purge time is 7000 ms and the flow rate of nitrogen is 10000 sccm.
[0136] (2-4) performing a first vacuum pumping process on the ALD equipment, the time of the first vacuum pumping process being 3000 ms;
[0137] (2-5) passivating the pretreated aluminum boat in an ozone atmosphere for 4000 ms at an ozone flow rate of 5000 sccm;
[0138] (2-6) Use nitrogen gas to purge the ozone in the ALD equipment for 6000 ms at a nitrogen flow rate of 10000 sccm;
[0139] (2-7) Using nitrogen to perform a second pipeline purge on the gaseous trimethylaluminum pipeline and the ozone pipeline of the ALD equipment, the second pipeline purge time is 6000 ms, and the flow rate of nitrogen is 10000 sccm;
[0140] (2-8) performing a second vacuuming treatment on the reaction container, wherein the time for the second vacuuming treatment is 3000 ms;
[0141] (3) After multiple cycles of passivation treatment, the ALD equipment is purged with nitrogen, and then the ALD equipment is evacuated and filled with nitrogen to return the ALD equipment to normal pressure and then taken out of the boat.
[0142] Reference Figure 4 , Figure 4 This is a schematic diagram of the surface of a battery cell without black edge contamination of the aluminum boat in Example 2.
[0143] The untreated aluminum boat and the aluminum boat treated in Examples 1 and 2 were applied to the ALD process of solar cell production, and the performance of the solar cell was tested and averaged, including the number of samples, U oc ,I sc , R ser , R sh , FF and E taThe test results are shown in Table 1 below; the EL yield and contamination ratio of the solar cell are statistically analyzed, and the results are shown in Table 2 below.
[0144] Table 1
[0145]
[0146] Table 2
[0147]
[0148] Referring to the data in Tables 1 and 2, it can be seen that when the aluminum boats obtained in Examples 1 and 2 are used in production, the efficiency and EL yield of the battery cells are significantly better than those of the untreated aluminum boats, and the contamination ratio is significantly lower than that of the untreated aluminum boats.
[0149] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0150] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims, and the description and drawings may be used to interpret the contents of the claims.
Claims
1. A passivation method for an aluminum boat, characterized in that: include: The aluminum boat is subjected to constant temperature preheating treatment; Performing multiple passivation treatments on the aluminum boat after the constant temperature preheating treatment; The passivation treatment includes: pre-treating the aluminum boat after the constant temperature preheating treatment in a gaseous trimethylaluminum atmosphere, and then passivating the pre-treated aluminum boat in an ozone gas atmosphere.
2. The passivation method of an aluminum boat according to claim 1, characterized in that: The temperature of the constant temperature preheating treatment is 235°C~250°C; And / or, the constant temperature preheating treatment time is 700s~1500s.
3. The passivation method of an aluminum boat according to claim 1, characterized in that: In a single passivation treatment, the pretreatment time is 1000ms~5000ms; And / or, in a single passivation treatment, the gas pressure of the gaseous trimethylaluminum atmosphere is 20 Torr~35 Torr.
4. The passivation method of an aluminum boat according to claim 1, characterized in that: In a single passivation treatment, the pre-treated aluminum boat is passivated in an ozone gas atmosphere for a period of 2000ms to 8000ms; And / or, in a single passivation treatment, the flow rate of ozone is 2000sccm~7000sccm.
5. The passivation method for an aluminum boat according to any one of claims 1 to 4, characterized in that: Before passivating the pre-treated aluminum boat in an ozone gas atmosphere, the method further includes: purging the gaseous trimethylaluminum with nitrogen; And / or, after passivating the pretreated aluminum boat in an ozone gas atmosphere, the method further includes: purging the ozone with nitrogen.
6. The passivation method of an aluminum boat according to claim 5, characterized in that: The time for purging the gaseous trimethylaluminum with nitrogen is 2000ms~5000ms; And / or, the flow rate of nitrogen used to purge the gaseous trimethylaluminum is 2000 sccm~10000 sccm.
7. The passivation method of an aluminum boat according to claim 5, characterized in that: The time for purging the ozone with nitrogen is 3000ms~10000ms; And / or, the flow rate of nitrogen used to purge the ozone is 5000 sccm~10000 sccm.
8. The passivation method for an aluminum boat according to any one of claims 1 to 4, characterized in that: The number of times of the multiple passivation treatments is 50 to 200 times.
9. An aluminum boat, characterized in that: The aluminum boat is obtained by passivation according to any one of claims 1 to 8.
10. A method for passivating a pre-finished battery cell, characterized in that: include: Provide pre-finished battery cells; Passivating the aluminum boat using the passivation method for the aluminum boat according to any one of claims 1 to 8; The passivated aluminum boat is used to receive the battery cell pre-finished product, and the battery cell pre-finished product is passivated.