Method for improving semi-slice power of solar cell and semi-slice cell assembly
Silicon oxide was grown through light and ozone oxidation, and the method of instantaneous multiple sources was adopted in a single cycle, which solved the problem of semi-slicing surface defects of solar cell cells and the alumina winding plating, and improved the component power and welding yield.
Patent Information
- Application Number
- CN202510326023.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-19
- Publication Date
- 2025-06-10
AI Technical Summary
The semi-slicing of existing solar cell cells produces major defects at the cut surface, affecting the battery efficiency and component power. The commonly used alumina deposition method leads to alumina plating, resulting in component power loss and poor welding.
By irradiating the half-sliced battery and oxidizing the ozone, thick silicon oxide is grown to improve the passivation effect; then, the method of instantaneous multiple sources is passed in a single cycle to reduce the depth of the source entering the gap between the silicon wafer and reduce the occurrence of winding plating.
The component power and welding yield are improved, the welding problem is reduced, the appearance of half-piece battery is improved, and the negative impact of alumina winding plating on component power is reduced.
Smart Images
Figure CN120129336A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of TOPCon cell preparation, and particularly relates to a method for improving the power of half-cut solar cells and a half-cut cell module. Background Art
[0002] With the continuous expansion of production by cross-border companies and industry companies, TOPCon cells have replaced PERC cells as the largest mass-produced cells currently, intensifying photovoltaic competition. Enterprises' demand for cost reduction and efficiency improvement is increasing day by day. At the same time, photovoltaic silicon-based cells are getting closer and closer to their efficiency limits. How to continue to improve cell efficiency and product competitiveness has become a difficult problem in the photovoltaic industry. Among them, solar cells such as BC cells and perovskite cells are being vigorously researched, and technologies such as polyfinger and double-sided TOPCon are also being continuously promoted. At the module end, the cells need to be cut in half to meet requirements such as airborne and open circuit voltage. However, cutting the cells in half will generate large defects at the cut surface, affecting cell efficiency and module power. Therefore, eliminating this defect is an urgent problem to be solved at present. The common method is to stack the sliced cells after slicing, deposit aluminum oxide at the cut surface, and use aluminum oxide to passivate the cut surface. However, after stacking, thick aluminum oxide is deposited on the cut surface, and there are gaps between the slices, which will cause the aluminum oxide to be plated around to the front and back of the cell, forming edge plating, resulting in power loss of the module. At the same time, large plating around is likely to cause poor soldering of the module. Summary of the Invention
[0003] In view of the deficiencies of the prior art, the present invention provides a method for improving the power of half-cut solar cell modules and a half-cut cell module. The present invention first performs light irradiation and ozone oxidation treatment on the slices to grow thick silicon oxide, improving the passivation effect and module power; then adopts a method of instantaneously passing the source multiple times within a single cycle to reduce the depth of the source entering the silicon wafer gap, reduce the generation of plating around, reduce the light absorption of plating around, further improve the module power and soldering yield, and at the same time can reduce the problem of poor soldering and improve the appearance of the half-cut cells.
[0004] The technical solution of the present invention is as follows:
[0005] In a first aspect of the present invention, a method for improving the power of half-cut solar cell modules is provided, and the method includes the following steps:
[0006] S1: Provide a chemical vapor deposition chamber, and a light source for downward irradiation is provided at the top of the chemical vapor deposition chamber; place the half-cut cell with the cut surface facing up into a carrier, send the carrier into the chamber, and perform vacuum pumping, leak detection, heating, and constant temperature treatment;
[0007] Wherein, a deposition opening is provided on the carrier, and the sliced end face of the half-cut cell is completely exposed from the deposition opening;
[0008] S2: Oxidize the half-sliced battery;
[0009] S3: Introduce TMA, nitrogen, and then nitrogen again; repeat the above process more than once, then introduce water vapor and nitrogen, and finally introduce nitrogen again;
[0010] S4: Repeat step S3 several times;
[0011] S5: Return to normal pressure, discharge the material, and cool it.
[0012] Preferably, in step S2, the oxidation treatment is to introduce ozone into the chemical vapor deposition chamber and perform light irradiation.
[0013] Preferably, the flow rate of the introduced ozone is 1000 - 10000 sccm, and the time is 10 - 300 s; the time of the light irradiation is 10 - 300 s.
[0014] Preferably, step S3 includes: introducing TMA and nitrogen, and then nitrogen again; repeat the above process 2 times, then introduce water vapor and nitrogen, and finally introduce nitrogen again.
[0015] Preferably, step S3 specifically includes:
[0016] S3-1: Introduce 100 - 10000 sccm of TMA and 1000 - 20000 sccm of nitrogen;
[0017] S3-2: Introduce 5000 - 30000 sccm of nitrogen;
[0018] S3-3: Introduce 100 - 10000 sccm of TMA and 1000 - 20000 sccm of nitrogen;
[0019] S3-4: Introduce 5000 - 30000 sccm of nitrogen;
[0020] S3-5: Introduce 100 - 10000 sccm of TMA and 1000 - 20000 sccm of nitrogen;
[0021] S3-6: Introduce 5000 - 30000 sccm of nitrogen;
[0022] S3-7: Introduce water vapor and nitrogen for 1 - 20 s;
[0023] S3-8: Introduce nitrogen.
[0024] Preferably, in steps S3-1, S3-3, and S3-5, the time for introducing TMA and nitrogen is 1 - 5 s for each.
[0025] Preferably, in steps S3-2, S3-4, and S3-6, the time for introducing nitrogen is 1 - 10 s for each.
[0026] Preferably, in step S3-7, the flow rate of the introduced water vapor is 1000-20000 sccm; the flow rate of the introduced nitrogen is 1000-20000 sccm.
[0027] Preferably, in step S3-8, the flow rate of the introduced nitrogen is 5000-30000 sccm, and the time is 1-20 s.
[0028] The second aspect of the present invention provides a half-sliced battery assembly obtained by the method described in the first aspect above.
[0029] The beneficial technical effects of the present invention are as follows:
[0030] By means of instantaneous multiple source introduction and purging within a single cycle, the present invention reduces the depth of the source entering the gaps between silicon wafers, thereby reducing the generation of overplating, reducing overplating light absorption, improving the power and welding yield of the assembly, and at the same time reducing the problem of poor welding and improving the appearance of the half-sliced battery; in addition, by light excitation, electron-hole pairs on the surface of the cut surface are generated, improving the oxidation reaction ability, growing thick silicon oxide, improving the surface passivation effect, and further improving the power of the assembly. Description of the Drawings
[0031] Figure 1 It is a schematic process flow diagram for improving the passivation of the cut surface of the half-sliced battery and reducing overplating of the present invention.
[0032] Figure 2 It is a schematic diagram of the placement of the half-sliced battery in the carrier.
[0033] In the figure: 1, the cut surface of the half-sliced battery; 2, the carrier; 3, the half-sliced battery
[0034] Figure 3 It is a schematic process diagram of depositing alumina on the existing half-sliced battery.
[0035] Figure 4 It is a half-cell obtained by the process method of Example 1 of the present invention.
[0036] Figure 5 It is a half-cell obtained by the process method of Comparative Example 1 of the present invention.
[0037] Figure 6 It is a half-cell obtained by the process method of Comparative Example 2 of the present invention. Detailed Embodiments
[0038] The present invention will be specifically described below in conjunction with embodiments.
[0039] Regarding the cut surface problem of the half-sliced battery, the prior art usually adopts Figure 3The method shown, that is, slicing the complete battery, stacking the cut sliced batteries uniformly, loading the sliced batteries with the cut surfaces facing up into the carrier, and then according to Figure 3 The method shown, specifically including first passing TMA, then passing nitrogen, then passing water, and finally passing nitrogen, cycling this process to complete the deposition of aluminum oxide and discharging. At this time, the deposition thickness of aluminum oxide is relatively deep. The present invention provides a method for improving the power of a half-sliced solar cell module, which is achieved by improving the passivation of the half-sliced surface and reducing overplating. The method includes: slicing the complete battery, as Figure 2 shown, stacking the cut half-sliced batteries 1 uniformly, loading the sliced batteries with the cut surfaces 1 facing up into the carrier 2. The carrier 2 is provided with a deposition opening, and the sliced end faces of the half-sliced batteries are completely exposed from the deposition opening. Sending the loaded carrier into the chemical vapor deposition chamber, a downward light source is installed above the chamber for light-assisted oxidation, and an input pipeline for introducing ozone, TMA, nitrogen, water vapor, etc. is also included; the process steps are evacuation, leak detection, heating, constant temperature, light-assisted oxidation, ALD deposition of aluminum oxide, and discharging.
[0040] It can be understood that the present invention does not limit the light source, and any light source type that can achieve the effects of the present invention is within the protection scope of the present invention. The light source of the present invention can be installed on the top of the existing chemical vapor deposition chamber by conventional methods in the art, and the present invention does not limit the specific installation method and the number of light sources.
[0041] In some embodiments, Figure 1 as shown, the method specifically includes the following steps:
[0042] (1) Provide a chemical vapor deposition chamber, place the half-sliced battery with the cut surface side facing up into the chamber of the chemical vapor deposition chamber, and perform conventional operations such as vacuum pumping, leak detection, heating, and constant temperature. Among them, heating means heating to the temperature at which the following reaction can occur.
[0043] (2) Light-assisted oxidation: Pass 1000 - 10000 sccm of ozone into the chamber, and turn on the light source for illumination. The illumination time is 10 - 300 s. Preferably, the input amount of ozone includes but is not limited to 1000 sccm, 2000 sccm, 4000 sccm, 6000 sccm, 8000 sccm, 10000 sccm; the illumination time includes but is not limited to 10 s, 50 s, 100 s, 150 s, 200 s, 250 s, 300 s.
[0044] (3) After the ozone-light treatment, deposit aluminum oxide by atomic layer deposition (ALD). The specific steps are as follows:
[0045] (3-1) Pass TMA and nitrogen: Pass 100 - 10,000 sccm of TMA and 1,000 - 20,000 sccm of nitrogen for 1 - 5 s. Preferably, the flow rate of TMA includes but is not limited to 100 sccm, 500 sccm, 1,000 sccm, 5,000 sccm, 8,000 sccm, 10,000 sccm; the flow rate of nitrogen includes but is not limited to 1,000 sccm, 5,000 sccm, 10,000 sccm, 15,000 sccm, 20,000 sccm; the time includes but is not limited to 1 s, 2 s, 3 s, 4 s, 5 s.
[0046] (3-2) Pass N 2 : Pass 5,000 - 30,000 sccm of nitrogen for 1 - 10 s to purge the TMA on the battery cross-section and gaps. Preferably, the flow rate of nitrogen includes but is not limited to 5,000 sccm, 10,000 sccm, 15,000 sccm, 20,000 sccm, 25,000 sccm, 30,000 sccm; the time includes but is not limited to 1 s, 4 s, 6 s, 8 s, 10 s.
[0047] (3-3) Pass TMA and nitrogen: Pass 100 - 10,000 sccm of TMA and 1,000 - 20,000 sccm of nitrogen for 1 - 5 s. Preferably, the flow rate of TMA includes but is not limited to 100 sccm, 500 sccm, 1,000 sccm, 5,000 sccm, 8,000 sccm, 10,000 sccm; the flow rate of nitrogen includes but is not limited to 1,000 sccm, 5,000 sccm, 10,000 sccm, 15,000 sccm, 20,000 sccm; the time includes but is not limited to 1 s, 2 s, 3 s, 4 s, 5 s.
[0048] (3-4) Pass N 2 : Pass 5,000 - 30,000 sccm of nitrogen for 1 - 10 s to purge the TMA on the battery cross-section and gaps. Preferably, the flow rate of nitrogen includes but is not limited to 5,000 sccm, 10,000 sccm, 15,000 sccm, 20,000 sccm, 25,000 sccm, 30,000 sccm; the time includes but is not limited to 1 s, 4 s, 6 s, 8 s, 10 s.
[0049] (3-5) Pass TMA and nitrogen: Pass 100 - 10,000 sccm of TMA and 1,000 - 20,000 sccm of nitrogen for 1 - 5 s. Preferably, the flow rate of TMA includes but is not limited to 100 sccm, 500 sccm, 1,000 sccm, 5,000 sccm, 8,000 sccm, 10,000 sccm; the flow rate of nitrogen includes but is not limited to 1,000 sccm, 5,000 sccm, 10,000 sccm, 15,000 sccm, 20,000 sccm; the time includes but is not limited to 1 s, 2 s, 3 s, 4 s, 5 s.
[0050] (3-6) Pass N 2 : Pass 5,000 - 30,000 sccm of nitrogen for 1 - 10 s to purge the TMA on the battery cut surface and gaps. Preferably, the flow rate of nitrogen includes but is not limited to 5,000 sccm, 10,000 sccm, 15,000 sccm, 20,000 sccm, 25,000 sccm, 30,000 sccm; the time includes but is not limited to 1 s, 4 s, 6 s, 8 s, 10 s.
[0051] (3-7) Pass steam and nitrogen: Pass 100 - 10,000 sccm of steam and 1,000 - 20,000 sccm of nitrogen for 1 - 20 s. Preferably, the flow rate of steam includes but is not limited to 1,000 sccm, 5,000 sccm, 10,000 sccm, 15,000 sccm, 20,000 sccm; the time includes but is not limited to 1 s, 4 s, 6 s, 8 s, 10 s, 14 s, 16 s, 18 s, 20 s.
[0052] (3-8) Pass N 2 ; Pass 5,000 - 30,000 sccm of nitrogen for 1 - 20 s to purge the water on the battery cut surface and gaps. Preferably, the flow rate of nitrogen includes but is not limited to 5,000 sccm, 10,000 sccm, 15,000 sccm, 20,000 sccm, 25,000 sccm, 30,000 sccm; the time includes but is not limited to 1 s, 4 s, 6 s, 8 s, 10 s, 14 s, 16 s, 18 s, 20 s.
[0053] It can be understood that in the above process, TMA is purged by N 2 after a very short source passing time, reducing the depth of TMA entering the battery gaps and being able to greatly reduce the width of alumina overplating in the battery gaps.
[0054] Performing the above steps in a cyclic process for 10 - 500 cycles can grow an alumina film layer with a specific thickness on the cut surface of the battery wafer.
[0055] (4) Discharge: After alumina production, back to normal pressure by filling with nitrogen, take out of the chamber and cool down.
[0056] Send the cells that have completed the half - slice passivation process to module encapsulation and conduct power tests.
[0057] The present invention will be further described below through examples and the like.
[0058] The present invention first tested the influence of light - irradiated oxidation on the thickness and passivation of silicon oxide on the slice.
[0059] Test Example 1:
[0060] (1) Light - assisted oxidation: Place the double - sided polished wafer with one side facing up in the chamber, evacuate, leak - check, heat up, keep at a constant temperature, introduce 5000 sccm ozone, and conduct light irradiation for 120 s to grow silicon oxide on the upper side, then back to normal pressure and take out of the chamber.
[0061] (2) Flip the wafer and repeat the process in (1) to grow silicon oxide on the other side as well.
[0062] (3) Use an ellipsometer and WCT120 to measure the thickness and passivation of silicon oxide on the polished wafer, and the results are shown in Table 1.
[0063] Comparative Test Example 1:
[0064] (1) Light - assisted oxidation: Place the double - sided polished wafer with one side facing up in the chamber, evacuate, leak - check, heat up, keep at a constant temperature, introduce 5000 sccm ozone for 120 s to grow silicon oxide, then back to normal pressure and take out of the chamber.
[0065] (2) Flip the wafer and repeat the process in (1) to grow silicon oxide on the other side as well.
[0066] (3) Use an ellipsometer and WCT120 to measure the thickness and passivation of silicon oxide on the polished wafer, and the results are shown in Table 1.
[0067] Table 1 Thickness of silicon oxide and implied open - circuit voltage of test examples and comparative test examples
[0068] Performance Index Silicon Oxide Thickness (nm) iVoc (V) Test Example 1 5 0.671 Comparative Test Example 1 2 0.645
[0069] Through the above tests, it can be seen that through light - assisted oxidation, the thickness of silicon oxide increases and the implied open - circuit voltage increases significantly, indicating that light - assisted oxidation can help increase the thickness of silicon oxide and improve the passivation effect of the cut surface at the same time.
[0070] Next, specifically study the influence of different passivation processes on the passivation and plating - around of the cut surface of the half - slice.
[0071] Example 1
[0072] A method for improving the power of a half-cut solar cell module, which is achieved by improving the passivation effect of the half-cut surface and reducing the plating around the cut surface. The method includes:
[0073] (1) Slicing and loading: The complete cells are sliced, and the cut cells are stacked neatly, with the cut surfaces facing up and loaded into the carrier.
[0074] (2) Light-assisted oxidation: The half-cell with the cut surface facing up in the carrier is sent into the chamber, and then evacuated, leak-tested, heated, and maintained at a constant temperature. 5000 sccm of ozone is introduced before depositing alumina, and light is irradiated for 100 s.
[0075] (3) After the ozone-light treatment, alumina is deposited by atomic layer deposition (ALD). The specific steps are as follows:
[0076] (3-1) Introduce TMA and nitrogen: Introduce 5000 sccm of TMA and 15000 sccm of nitrogen, both for 2 s;
[0077] (3-2) Introduce N 2 : Introduce 20000 sccm of nitrogen for 3 s;
[0078] (3-3) Introduce TMA and nitrogen: Introduce 5000 sccm of TMA and 15000 sccm of nitrogen, both for 2 s;
[0079] (3-4) Introduce N 2 : Introduce 20000 sccm of nitrogen for 3 s;
[0080] (3-5) Introduce TMA and nitrogen: Introduce 5000 sccm of TMA and 15000 sccm of nitrogen, both for 2 s;
[0081] (3-6) Introduce N 2 : Introduce 20000 sccm of nitrogen for 3 s;
[0082] (3-7) Introduce water vapor and nitrogen: Introduce 3000 sccm of water vapor and 17000 sccm of nitrogen for 8 s;
[0083] (3-8) Introduce N 2 ; Introduce 20000 sccm of nitrogen for 10 s.
[0084] The above steps are cycled 400 times, and an alumina film layer with a thickness of 50 nm grows on the cut surface of the cell.
[0085] (4) Discharging: Return to normal pressure, exit the chamber and cool down.
[0086] The plating appearance after the above treatment is as shown in Figure 4As shown. The processed slices are sent for component encapsulation and power testing, and the results are shown in Table 2.
[0087] Comparative Example 1
[0088] A method for improving the power of half-sliced solar cell components, comprising:
[0089] (1) Slicing and loading: The complete cells are sliced, the cut cell wafers are stacked together uniformly, and the cut surfaces are loaded into the carrier with the cut surfaces facing up.
[0090] (2) Light-assisted oxidation: The half-cell wafers in the loaded carrier are sent into the chamber with the cut surfaces facing up, and the chamber is evacuated, leak-tested, heated up, and kept at a constant temperature. 5000 sccm of ozone is introduced before depositing aluminum oxide, and light irradiation is carried out for 100 s.
[0091] (3) After the ozone-light treatment, aluminum oxide is deposited by atomic layer deposition (ALD), and the specific steps are as follows:
[0092] (3-1) Introducing TMA and nitrogen: 5000 sccm of TMA and 15000 sccm of nitrogen are introduced for 6 s.
[0093] (3-2) Introducing N 2 : 20000 sccm of nitrogen is introduced for 9 s.
[0094] (3-3) Introducing water vapor and nitrogen: 3000 sccm of water vapor and 17000 sccm of nitrogen are introduced for 8 s.
[0095] (3-4) Introducing N 2 ; 20000 sccm of nitrogen is introduced for 10 s.
[0096] The above steps are cycled 400 times, and an aluminum oxide film layer with a thickness of 50 nm grows on the cut surface.
[0097] (4) Discharging: Return to normal pressure, exit the chamber and cool down.
[0098] The appearance of the plating around after being processed by the above process steps is as Figure 5 shown. The processed slices are sent for component encapsulation and power testing, and the results are shown in Table 2.
[0099] Comparative Example 2
[0100] A method for improving the power of half-sliced solar cell components, comprising:
[0101] (1) Slicing and loading: The complete cells are sliced, the cut cell wafers are stacked together uniformly, and the cut surfaces are loaded into the carrier with the cut surfaces facing up.
[0102] (2) Light-assisted oxidation: Place the half-cell with the carrier loaded into the chamber with the cut surface facing up, evacuate, leak-check, heat up, and maintain a constant temperature. Before depositing aluminum oxide, introduce 5000 sccm of ozone and perform light irradiation for 100 s.
[0103] (3) Deposit aluminum oxide by atomic layer deposition (ALD), and the specific steps are as follows:
[0104] (3-1) Introduce TMA and nitrogen: Introduce 5000 sccm of TMA and 15000 sccm of nitrogen for 2 s.
[0105] (3-1) Introduce N 2 : Introduce 20000 sccm of nitrogen for 3 s.
[0106] (3-1) Introduce water vapor and nitrogen: Introduce 3000 sccm of water vapor and 17000 sccm of nitrogen for 8 s.
[0107] (3-1) Introduce N 2 ; Introduce 20000 sccm of nitrogen for 10 s.
[0108] Perform the above steps in a cyclic process for 400 cycles, and an aluminum oxide film layer with a thickness of 50 nm grows on the cut surface.
[0109] (4) Discharge: Return to normal pressure, take out of the chamber and cool.
[0110] The appearance of the edge plating after being processed by the above process steps is as Figure 6 shown. Send the sliced pieces processed above to component packaging for power testing, and the results are shown in Table 2.
[0111] Example 2
[0112] A method for improving the power of a half-sliced solar cell module, which is achieved by improving the passivation effect of the cut surface of the half-slice and reducing edge plating on the cut surface. The method includes:
[0113] (1) Slicing and loading: Slice the complete cell, stack the cut cell pieces neatly, and load them into the carrier with the cut surfaces facing up uniformly.
[0114] (2) Light-assisted oxidation: Place the half-cell with the carrier loaded into the chamber with the cut surface facing up, evacuate, leak-check, heat up, and maintain a constant temperature. Before depositing aluminum oxide, introduce 5000 sccm of ozone and perform light irradiation for 120 s.
[0115] (3) After ozone-light treatment, deposit aluminum oxide by atomic layer deposition (ALD), and the specific steps are as follows:
[0116] (3-1) Pass TMA and nitrogen: Pass 5000 sccm of TMA and 15000 sccm of nitrogen for 2 s.
[0117] (3-2) Pass N 2 : Pass 20000 sccm of nitrogen for 3 s.
[0118] (3-3) Pass TMA and nitrogen: Pass 5000 sccm of TMA and 15000 sccm of nitrogen for 2 s.
[0119] (3-4) Pass N 2 : Pass 20000 sccm of nitrogen for 3 s.
[0120] (3-5) Pass TMA and nitrogen: Pass 5000 sccm of TMA and 15000 sccm of nitrogen for 2 s.
[0121] (3-6) Pass N 2 : Pass 20000 sccm of nitrogen for 3 s.
[0122] (3-7) Pass steam and nitrogen: Pass 3000 sccm of steam and 17000 sccm of nitrogen for 8 s.
[0123] (3-8) Pass N 2 ; Pass 20000 sccm of nitrogen for 10 s.
[0124] Perform the above steps in a cyclic process for 400 cycles, and an alumina film layer with a thickness of 50 nm grows on the section.
[0125] (4) Discharge: Return to normal pressure, discharge from the chamber and cool.
[0126] Send the sliced pieces processed above to component packaging and conduct power testing. The results are shown in Table 2.
[0127] Comparative Example 3
[0128] A method for improving the power of a half-sliced component of a solar cell, comprising:
[0129] (1) Slicing and loading: Slice the complete battery, stack the cut battery pieces neatly, and load them into the carrier with the cut surfaces facing up uniformly.
[0130] (2) Ozone oxidation: Send the half-cell with the cut surface facing up into the chamber after loading the carrier, and perform evacuation, leak detection, heating, and constant temperature. Pass 5000 sccm of ozone for 120 s before depositing alumina.
[0131] (3) After ozone treatment, deposit alumina by atomic layer deposition (ALD). The specific steps are as follows:
[0132] (3-1) Pass TMA and nitrogen: Pass 5000 sccm of TMA and 15000 sccm of nitrogen for 2 s.
[0133] (3-2) Pass N 2 : Pass 20000 sccm of nitrogen for 3 s.
[0134] (3-3) Pass TMA and nitrogen: Pass 5000 sccm of TMA and 15000 sccm of nitrogen for 2 s.
[0135] (3-4) Pass N 2 : Pass 20000 sccm of nitrogen for 3 s.
[0136] (3-5) Pass TMA and nitrogen: Pass 5000 sccm of TMA and 15000 sccm of nitrogen for 2 s.
[0137] (3-6) Pass N 2 : Pass 20000 sccm of nitrogen for 3 s.
[0138] (3-7) Pass water vapor and nitrogen: Pass 3000 sccm of water vapor and 17000 sccm of nitrogen for 8 s;
[0139] (3-8) Pass N 2 ; Pass 20000 sccm of nitrogen for 10 s.
[0140] Perform a cyclic process of 400 cycles on the above steps, and an alumina film layer with a thickness of 50 nm grows on the section.
[0141] (4) Discharge: Return to normal pressure, discharge from the chamber and cool.
[0142] Subsequently, it is sent to component packaging for power testing, and the results are shown in Table 2.
[0143] Comparative Example 4
[0144] A method for improving the power of a half-cut slice component of a solar cell, including:
[0145] (1) Slice loading: Slice the complete battery, stack the cut battery slices neatly, and load them into the carrier with the cut surface facing up uniformly.
[0146] (2) Deposit alumina by atomic layer deposition (ALD), and the specific steps are as follows:
[0147] (2-1) Pass TMA and nitrogen: Pass 5000 sccm of TMA and 15000 sccm of nitrogen for 2 s.
[0148] (2-2) Pass N 2: Introduce 20000 sccm of nitrogen gas for 3 s.
[0149] (2 - 3) Introduce TMA and nitrogen gas: Introduce 5000 sccm of TMA and 15000 sccm of nitrogen gas for 2 s.
[0150] (2 - 4) Introduce N 2 : Introduce 20000 sccm of nitrogen gas for 3 s.
[0151] (2 - 5) Introduce TMA and nitrogen gas: Introduce 5000 sccm of TMA and 15000 sccm of nitrogen gas for 2 s.
[0152] (2 - 6) Introduce N 2 : Introduce 20000 sccm of nitrogen gas for 3 s.
[0153] (2 - 7) Introduce water vapor and nitrogen gas: Introduce 3000 sccm of water vapor and 17000 sccm of nitrogen gas for 8 s.
[0154] (2 - 8) Introduce N 2 ; Introduce 20000 sccm of nitrogen gas for 10 s.
[0155] Perform the above steps in a cyclic process for 400 cycles, and an alumina film layer with a thickness of 50 nm grows on the section.
[0156] (4) Discharge: Return to normal pressure, take out of the chamber and cool.
[0157] Send the slices processed above to component encapsulation and perform power testing. The results are shown in Table 2.
[0158] Table 2 Performance testing of slices obtained by the processes of the examples and comparative examples
[0159] Performance Index FF (%) Voc (V) Isc (A) <![CDATA[P max (W)]]> Welding Yield Example 1 80.18 58.51 13.61 638.5 99.0％ Example 2 80.19 58.52 13.61 638.7 98.9％ Comparative Example 1 80.17 58.50 13.60 637.8 95.1％ Comparative Example 2 80.01 58.49 13.60 636.5 99.1％ Comparative Example 3 80.15 58.47 13.60 637.3 98.8％ Comparative Example 4 80.13 58.43 13.60 636.8 98.7％
[0160] From Table 2 and Figure 4 - Figure 6It can be seen that the winding width of Example 1 and Comparative Example 2 is significantly reduced, and Comparative Example 1 has a slight winding plating close to the pad point (i.e., the electrode contact point on the solar cell), and there is a risk of poor welding, indicating that instantaneous source passing is beneficial to winding plating, and the difference in welding yield can reflect its influence on winding plating, but the power of the component of Comparative Example 2 is poor, indicating that instantaneous source passing needs to be repeated multiple times to ensure the quality of the aluminum oxide film, thereby ensuring the stability of the component power. The present invention can greatly reduce the scope of winding plating without reducing the component power by superimposing purging with instantaneous multiple source passing, and at the same time can reduce the influence of winding plating on the component power and yield. Comparing Examples 2-3 and Comparative Examples 2-4, combined with Tables 1 and 2, it can be seen that ozone treatment before aluminum oxide to grow silicon oxide can improve the passivation effect and component power, and light-assisted oxidation can increase the thickness of the grown silicon oxide, so that the silicon oxide passivation effect is better, thereby increasing the power of the component.
[0161] Combining the embodiments of the present invention, the comparative examples and the obtained test results, it can be seen that instantaneous multiple source passes in a single cycle can reduce the depth of the source entering the battery gap during the source pass process, which can reduce the generation of plating and reduce the occurrence of component yield problems. Less plating can reduce the impact on battery light absorption and increase component power. At the same time, before depositing aluminum oxide, light-assisted oxidation is used to increase the thickness of silicon oxide growth and improve its passivation effect, thereby achieving the purpose of increasing component power. This solution only requires the addition of an ozone generator to prepare ozone and an LED lamp to provide a light source. The modification cost is low, the ozone oxidation time is short, and no additional time is added when depositing aluminum oxide. The impact on production capacity is small, which is conducive to large-scale promotion of production lines.
[0162] Based on this result, the instantaneous multiple source passes within a single cycle in the method described in this invention can also be applied to the ALD process of batteries such as PERC and BC that use single-sided aluminum oxide to reduce the occurrence of wrap-around plating.
[0163] The above is only a preferred embodiment of the present invention, and the present invention is not limited to the above embodiments. It is understood that other improvements and changes directly derived or associated by those skilled in the art without departing from the spirit and concept of the present invention should be considered to be included in the protection scope of the present invention.
Claims
1. A method for increasing the power of a half-cut solar cell assembly, characterized in that: The method comprises the following steps: S1: Provide a chemical vapor deposition chamber, wherein a light source for irradiating downward is provided on the top of the chemical vapor deposition chamber; place a half-cut cell into a carrier with the cut surface facing upward, send the carrier into the chamber, and perform vacuuming, leak detection, temperature increase, and constant temperature treatment; Wherein, a deposition opening is provided on the carrier, and the sliced end surface of the half-sliced battery is completely exposed from the deposition opening; S2: oxidation treatment of the half-cut cell; S3: introducing TMA and nitrogen, and then introducing nitrogen; repeating the above process once more, and then introducing water vapor and nitrogen, and finally introducing nitrogen; S4: Repeat step S3 several times; S5: Return to normal pressure, discharge, and cool.
2. The method according to claim 1, characterized in that In step S2, the oxidation treatment is to introduce ozone into the vapor deposition chamber and perform light irradiation.
3. The method according to claim 2, characterized in that The ozone introduction amount is 1000-10000sccm, and the time is 10-300s; the illumination time is 10-300s.
4. The method according to claim 1, characterized in that: Step S3 includes: introducing TMA and nitrogen, and then introducing nitrogen; repeating the above process twice, then introducing water vapor and nitrogen, and finally introducing nitrogen.
5. The method according to claim 1, characterized in that Step S3 specifically includes: S3-1: introducing 100-10000 sccm TMA and 1000-20000 sccm nitrogen; S3-2: introducing 5000-30000 sccm nitrogen; S3-3: introducing 100-10000 sccm TMA and 1000-20000 sccm nitrogen; S3-4: introducing 5000-30000 sccm nitrogen; S3-5: introducing 100-10000 sccm TMA and 1000-20000 sccm nitrogen; S3-6: introducing 5000-30000 sccm nitrogen; S3-7: introducing water vapor and nitrogen for 1-20 seconds; S3-8: Introduce nitrogen gas.
6. The method according to claim 5, characterized in that In steps S3-1, S3-3 and S3-5, the time for introducing TMA and nitrogen is 1-5 s.
7. The method according to claim 5, characterized in that In steps S3-2, S3-4 and S3-6, the time for introducing nitrogen is 1-10 seconds.
8. The method according to claim 5, characterized in that In step S3-7, the amount of water vapor introduced is 1000-20000 sccm; the amount of nitrogen introduced is 1000-20000 sccm.
9. The method according to claim 5, characterized in that In step S3-8, the amount of nitrogen introduced is 5000-30000 sccm, and the time is 1-20 s.
10. A half-cut battery assembly obtained by the method according to any one of claims 1 to 9.