Air inlet structure and solar cell coating equipment

Abstract

The utility model relates to the technical field of solar cells, in particular to an air inlet structure and solar cell coating equipment. The air inlet structure is used for being connected with an air inlet of the reaction chamber and comprises a first air inlet pipeline and a second air inlet pipeline, the first air inlet pipeline extends into the reaction chamber from the air inlet, is provided with a first spraying opening and is used for conveying aluminum-containing precursor molecules, and the second air inlet pipeline extends into the reaction chamber from the air inlet and is provided with a second spraying opening. A second spraying opening and a third spraying opening are formed in the second air inlet pipeline in a spaced mode, the second spraying opening is formed in the side, close to the air inlet, of the second air inlet pipeline, the third spraying opening is formed in the side, away from the air inlet, of the second air inlet pipeline, and the second air inlet pipeline is used for conveying oxygen-containing precursor molecules; and the extension length of the first gas inlet pipeline in the reaction chamber is shorter than that of the second gas inlet pipeline in the reaction chamber. The solar cell coating equipment comprises the air inlet structure. According to the utility model, the coating uniformity of the silicon wafer can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of solar cells, and particularly relates to an air inlet structure and a solar cell coating device. Background Technique

[0002] Due to the good passivation effect of alumina, alumina materials are introduced into solar cells as passivation layers, and its preparation technologies mainly include atomic layer deposition (ALD) and plasma enhanced chemical vapor deposition (PECVD). The ALD (Atomic Layer Deposition) atomic deposition technology of alumina is a technology that realizes the deposition of alumina by alternately introducing aluminum-containing precursor molecules and oxygen-containing precursor molecules onto the surface of a substrate. The principle of the ALD technology is to form a monolayer of molecules on the substrate surface, and these monolayer molecules can be converted into an oxide film through chemical reactions.

[0003] The coating uniformity of the ALD equipment has an important impact on the conversion efficiency of solar cells. At present, the following defects exist in the spray air inlet method at the furnace mouth: process gases can be evenly distributed from the furnace mouth of the reaction chamber to the furnace tail. Since the process gases are only introduced through the spray at the furnace mouth and then evenly distributed to the furnace tail, and the reaction chamber is in a vacuum state, when the process gases diffuse from the furnace mouth to the furnace tail, the concentration difference between the gas concentration at the furnace tail and the gas concentration at the furnace mouth is relatively large, resulting in differences in the coating uniformity before and after the reaction using the ALD process, and further causing the conversion efficiency of the produced solar cells to be not high. Summary of the Utility Model

[0004] The main purpose of the utility model is to propose an air inlet structure and a solar cell coating device, aiming to solve the technical problem that when the existing equipment coats films, the concentration difference between the gas concentration at the furnace tail and the gas concentration at the furnace mouth is relatively large when the process gases diffuse from the furnace mouth to the furnace tail, resulting in differences in the coating uniformity before and after the reaction using the ALD process, and further causing the conversion efficiency of the produced solar cells to be not high.

[0005] To achieve the above object, the utility model proposes an air inlet structure for connecting the air inlet of a reaction chamber to form an alumina film on the surface of a silicon wafer in the reaction chamber. The air inlet structure includes:

[0006] A first air inlet pipe extending from the air inlet to the inside of the reaction chamber. The first air inlet pipe is provided with a first spray port, and the first air inlet pipe is used for transporting aluminum-containing precursor molecules;

[0007] A second intake pipe that extends from the intake port to the interior of the reaction chamber. The second intake pipe is provided with a second spray port and a third spray port at intervals. The second spray port is arranged on the side of the second intake pipe close to the intake port, and the third spray port is arranged on the side of the second intake pipe away from the intake port. The second intake pipe is used to transport oxygen-containing precursor molecules;

[0008] Wherein, the extension length of the first intake pipe in the reaction chamber is shorter than that of the second intake pipe in the reaction chamber.

[0009] In some embodiments, along the length direction of the reaction chamber, the first intake pipe extends to a position close to the intake port, and the second intake pipe extends to the central position of the reaction chamber.

[0010] In some embodiments, the reaction chamber has a top side wall and a bottom side wall arranged oppositely, and the first spray port is arranged facing the bottom side wall.

[0011] In some embodiments, the reaction chamber has a top side wall and a bottom side wall arranged oppositely, and the reaction chamber has a sealed side wall arranged oppositely to the intake port. The second spray port is arranged facing the top side wall, and the third spray port is arranged facing the sealed side wall.

[0012] In some embodiments, the first intake pipe includes:

[0013] A first pipeline, one end of which is connected to a first process pipeline for transporting the aluminum-containing precursor molecules;

[0014] A second pipeline, one end of which is connected to the end of the first pipeline away from the first process pipeline;

[0015] A third pipeline, one end of which is connected to the end of the second pipeline away from the first pipeline;

[0016] Wherein, the second pipeline and the third pipeline form a T-shaped structure, and the first spray port is arranged on the third pipeline.

[0017] In some embodiments, the second intake pipe includes:

[0018] A fourth pipeline, one end of which is connected to a second process pipeline for transporting the oxygen-containing precursor molecules;

[0019] A fifth pipeline, one end of which is connected to the end of the fourth pipeline away from the second process pipeline;

[0020] The sixth pipeline, one end of the sixth pipeline is connected to the end of the fifth pipeline facing away from the fourth pipeline;

[0021] The seventh pipeline, one end of the seventh pipeline is connected to the end of the sixth pipeline facing away from the fifth pipeline;

[0022] Wherein, the fifth pipeline, the sixth pipeline and the seventh pipeline form a Z-shaped structure, the second spray port is arranged on the sixth pipeline, and the third spray port is arranged on the seventh pipeline.

[0023] In some embodiments, the aperture diameters of the first spray port, the second spray port and the third spray port are all 2 mm.

[0024] In some embodiments, a first connecting portion is arranged at the air inlet, a second connecting portion is arranged on the side of the first air inlet pipeline close to the air inlet, and a third connecting portion is arranged on the side of the second air inlet pipeline close to the air inlet;

[0025] Wherein, the second connecting portion and the first connecting portion are connected by bolts to connect the first air inlet pipeline and the reaction chamber together; the third connecting portion and the first connecting portion are connected by bolts to connect the second air inlet pipeline and the reaction chamber together.

[0026] In some embodiments, at least two of the first spray ports are arranged on the first air inlet pipeline; at least two of the second spray ports are arranged on the second air inlet pipeline.

[0027] Correspondingly, the present invention also provides a solar cell coating device, including the air inlet structure described in any of the above embodiments.

[0028] Compared with the prior art, the beneficial effects of the present invention are:

[0029] In the technical solution of the present utility model, an aluminum-containing precursor molecule and an oxygen-containing precursor molecule are respectively introduced into the reaction chamber through the first intake pipe and the second intake pipe successively. Exemplarily, for example, the aluminum-containing precursor molecule can be first introduced into the reaction chamber through the first intake pipe, and after an interval of about half a minute (within the above interval time, the aluminum-containing precursor molecule has sufficient time to uniformly adhere to the surface of the silicon wafer), then the oxygen-containing precursor molecule is introduced into the reaction chamber through the second intake pipe, so that the oxygen-containing precursor molecule and the aluminum-containing precursor molecule can undergo a sufficient oxidation reaction on the surface of the silicon wafer. By adopting the above intake mode, on the one hand, it is beneficial to improve the uniformity of the aluminum oxide film formed on the surface of the silicon wafer and avoid differences in the coating uniformity on the surface of the silicon wafer; on the other hand, it is beneficial to prevent the aluminum-containing precursor molecule and the oxygen-containing precursor molecule from directly contacting and undergoing a violent reaction at the spray nozzle, thereby causing blockage of the spray nozzle and affecting the normal ejection of the subsequent aluminum-containing precursor molecule and oxygen-containing precursor molecule.

[0030] Further, in the present utility model, since the aluminum-containing precursor molecule is first introduced into the reaction chamber and the oxygen-containing precursor molecule is introduced into the reaction chamber only after waiting for a certain interval, the aluminum-containing precursor molecule has relatively sufficient time to adhere to the surface of the silicon wafer. After the oxygen-containing precursor molecule is subsequently introduced into the reaction chamber, the oxygen-containing precursor molecule will only react with the aluminum-containing precursor molecule on the surface of the silicon wafer, thereby forming an aluminum oxide film on the surface of the silicon wafer and realizing silicon wafer coating. Therefore, in order to accelerate the silicon wafer coating efficiency, improve the silicon wafer coating uniformity, and save production costs at the same time, only one spray nozzle is provided on the first intake pipe for introducing the aluminum-containing precursor molecule into the reaction chamber, and at least two spray nozzles are provided on the second intake pipe for simultaneously introducing the oxygen-containing precursor molecule into the reaction chamber. In addition, since only one spray nozzle is provided on the first intake pipe, the first intake pipe is set slightly shorter considering the production cost, and since two spray nozzles are provided on the second intake pipe, the second intake pipe is set slightly longer considering the spray effect. By adopting the above design, the oxygen-containing precursor molecule can be sprayed into the reaction chamber in segments, so that the oxygen-containing precursor molecule can quickly diffuse in the reaction chamber in a short time, ensuring that the oxygen-containing precursor molecule can quickly fill the entire reaction chamber, making up for the deficiency that the oxygen-containing precursor molecule cannot be uniformly dispersed in the reaction chamber when sprayed at a single position, resulting in poor coating uniformity on the surface of the silicon wafer.

[0031] The solar cell coating equipment applying the above intake structure is beneficial to improving the coating uniformity of the solar cell, and thus beneficial to improving the conversion efficiency of the solar cell. Description of the Drawings

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0033] Figure 1 Schematic diagram of the overall structure of the intake structure provided by an embodiment of the present invention;

[0034] Figure 2 Schematic diagram of the structure of the intake structure provided by an embodiment of the present invention at the intake port;

[0035] Figure 3 For Figure 2 Partial enlarged view at A in

[0036] Figure 4 Schematic diagram of the structure of the first intake pipe in the intake structure provided by an embodiment of the present invention;

[0037] Figure 5 Bottom view of the structure of the first intake pipe in the intake structure provided by an embodiment of the present invention;

[0038] Figure 6 Schematic diagram of the structure of the second intake pipe in the intake structure provided by an embodiment of the present invention;

[0039] Figure 7 Top view of the structure of the second intake pipe in the intake structure provided by an embodiment of the present invention.

[0040] Explanation of the reference numerals in the drawings:

[0041] 100 - reaction chamber;

[0042] 110 - intake port; 120 - first connection part;

[0043] 200 - first intake pipe;

[0044] 210 - first spray port; 220 - first pipeline; 230 - second pipeline; 240 - third pipeline; 250 - second connection part;

[0045] 300 - second intake pipe;

[0046] 310 - second spray port; 320 - third spray port; 330 - fourth pipeline; 340 - fifth pipeline; 350 - sixth pipeline; 360 - seventh pipeline; 370 - third connection part;

[0047] 400 - first process pipeline;

[0048] 500 - The second process pipeline.

[0049] The realization of the purpose, functional characteristics and advantages of the present utility model will be further described with reference to the embodiments and the accompanying drawings. Specific embodiments

[0050] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments in the present utility model, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present utility model.

[0051] It should be noted that if there are directional indications (such as up, down, left, right, front, back,...) involved in the embodiments of the present utility model, the directional indications are only used to explain the relative positional relationship and movement conditions between components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0052] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present utility model, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, if "and / or", "and / or" or "and / or" appear throughout the text, their meanings include three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or a solution where A and B are satisfied simultaneously. In addition, the technical solutions between the embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present utility model.

[0053] Due to its good passivation effect, alumina material is introduced into solar cells as a passivation layer, and its preparation technologies mainly include atomic layer deposition (ALD) and plasma enhanced chemical vapor deposition (PECVD). The ALD (Atomic Layer Deposition) atomic deposition technology of alumina is a technology that realizes the deposition of alumina by alternately introducing aluminum-containing precursor molecules and oxygen-containing precursor molecules onto the substrate surface. The principle of the ALD technology is to form a monolayer of molecules on the substrate surface, and these monolayer molecules can be converted into oxide films through chemical reactions.

[0054] The uniformity of film deposition by an ALD device has an important impact on the conversion efficiency of solar cells. At present, the following defects exist in the gas inlet method of spray at the furnace mouth: Process gases can be evenly distributed from the furnace mouth of the reaction chamber to the furnace tail. Since the gases only enter through spray at the furnace mouth and then are evenly distributed to the furnace tail, and the reaction chamber is in a vacuum state, when the process gases diffuse from the furnace mouth to the furnace tail, the concentration difference between the gas concentration at the furnace tail and the gas concentration at the furnace mouth is relatively large, resulting in differences in film deposition uniformity before and after using the ALD process reaction, and further causing the conversion efficiency of the produced solar cells to be not high.

[0055] To solve the technical problem that when using the existing equipment for film deposition, when the process gases diffuse from the furnace mouth to the furnace tail, the concentration difference between the gas concentration at the furnace tail and the gas concentration at the furnace mouth is relatively large, resulting in differences in film deposition uniformity before and after using the ALD process reaction, and further causing the conversion efficiency of the produced solar cells to be not high, referring to Figures 1 to 7 , an embodiment of the present utility model provides an air inlet structure. This air inlet structure is used to connect the air inlet 110 of the reaction chamber 100 to form an aluminum oxide film on the surface of the silicon wafer in the reaction chamber 100. The air inlet structure includes a first air inlet pipe 200 and a second air inlet pipe 300. The first air inlet pipe 200 extends from the air inlet 110 to the inside of the reaction chamber 100. The first air inlet pipe 200 is provided with a first spray port 210. The first air inlet pipe 200 is used to transport aluminum-containing precursor molecules (exemplarily, for example, the aluminum-containing precursor molecules can be trimethylaluminum). The second air inlet pipe 300 extends from the air inlet 110 to the inside of the reaction chamber 100. The second air inlet pipe 300 is provided with a second spray port 310 and a third spray port 320 at intervals. The second spray port 310 is arranged on the side of the second air inlet pipe 300 close to the air inlet 110, and the third spray port 320 is arranged on the side of the second air inlet pipe 300 away from the air inlet 110. The second air inlet pipe 300 is used to transport oxygen-containing precursor molecules (exemplarily, for example, the oxygen-containing precursor molecules can be water vapor). Among them, the extension length of the first air inlet pipe 200 inside the reaction chamber 100 is shorter than the extension length of the second air inlet pipe 300 inside the reaction chamber 100.

[0056] Specifically, in this embodiment, the reaction chamber 100 is a place where an oxidation reaction occurs to form an aluminum oxide film on the surface of the silicon wafer. Inside the reaction chamber 100, along the length direction of the reaction chamber 100, a wafer carrier boat is provided, and on the wafer carrier boat, a number of silicon wafers are arranged at intervals. The surface of the silicon wafer to be coated faces the side wall of the reaction chamber. When coating the silicon wafer, first, an aluminum-containing precursor molecule is introduced into the reaction chamber 100 through the first intake pipe 200, so that the aluminum-containing precursor molecule first adheres to the surface of the silicon wafer to form a uniform film layer. Then, an oxygen-containing precursor molecule is introduced into the reaction chamber 100 through the second intake pipe 300, so that the oxygen-containing precursor molecule and the aluminum-containing precursor molecule undergo an oxidation reaction on the surface of the silicon wafer, and thus an aluminum oxide film is formed on the surface of the silicon wafer, realizing the coating of the silicon wafer. The coated silicon wafer can be used in the production of solar cells.

[0057] Furthermore, in this embodiment, the aluminum-containing precursor molecule and the oxygen-containing precursor molecule are respectively introduced into the reaction chamber 100 through the first intake pipe 200 and the second intake pipe 300 in sequence. Exemplarily, for example, the aluminum-containing precursor molecule can be first introduced into the reaction chamber 100 through the first intake pipe 200, and after an interval of about half a minute (during this interval, the aluminum-containing precursor molecule has sufficient time to uniformly adhere to the surface of the silicon wafer), the oxygen-containing precursor molecule is then introduced into the reaction chamber 100 through the second intake pipe 300, so that the oxygen-containing precursor molecule and the aluminum-containing precursor molecule can undergo a sufficient oxidation reaction on the surface of the silicon wafer. By adopting the above intake method, on the one hand, it is beneficial to improve the uniformity of the aluminum oxide film formed on the surface of the silicon wafer and avoid differences in the coating uniformity on the surface of the silicon wafer; on the other hand, it is beneficial to prevent the aluminum-containing precursor molecule and the oxygen-containing precursor molecule from directly contacting and undergoing a violent reaction at the spray nozzle, thereby causing blockage of the spray nozzle and affecting the normal spraying of the subsequent aluminum-containing precursor molecule and oxygen-containing precursor molecule.

[0058] Further, in this embodiment, since the aluminum-containing precursor molecules are first introduced into the reaction chamber 100 and the oxygen-containing precursor molecules are introduced into the reaction chamber 100 after a certain interval, the aluminum-containing precursor molecules have sufficient time to adhere to the surface of the silicon wafer. After the oxygen-containing precursor molecules are subsequently introduced into the reaction chamber 100, the oxygen-containing precursor molecules will only react with the aluminum-containing precursor molecules on the surface of the silicon wafer, thereby forming an aluminum oxide film on the surface of the silicon wafer to achieve silicon wafer coating. Therefore, in order to accelerate the silicon wafer coating efficiency, improve the silicon wafer coating uniformity, and save production costs at the same time, only one spray port is provided on the first intake pipe 200 for introducing the aluminum-containing precursor molecules into the reaction chamber 100, and at least two spray ports are provided on the second intake pipe 300 for simultaneously introducing the oxygen-containing precursor molecules into the reaction chamber 100. In addition, since only one spray port is provided on the first intake pipe 200, the first intake pipe 200 is set slightly shorter considering the production cost. Since two spray ports are provided on the second intake pipe 300, the second intake pipe 300 is set slightly longer considering the spraying effect. By adopting the above design, the oxygen-containing precursor molecules can be sprayed into the reaction chamber 100 in sections, so that the oxygen-containing precursor molecules can quickly diffuse in the reaction chamber 100 in a short time, ensuring that the oxygen-containing precursor molecules can quickly fill the entire reaction chamber 100, making up for the deficiency that the oxygen-containing precursor molecules cannot be evenly dispersed in the reaction chamber 100 when sprayed at a single position, and finally resulting in poor coating uniformity on the surface of the silicon wafer.

[0059] In some embodiments, referring to Figure 1 , along the length direction of the reaction chamber 100, the first intake pipe 200 extends to a position close to the air inlet 110, and the second intake pipe 300 extends to the central position of the reaction chamber 100.

[0060] Specifically, in this embodiment, since the aluminum-containing precursor molecules are first introduced into the reaction chamber 100 and the oxygen-containing precursor molecules are introduced into the reaction chamber 100 after a certain interval, the aluminum-containing precursor molecules have sufficient time to adhere to the surface of the silicon wafer compared with the oxygen-containing precursor molecules. Therefore, the first intake pipe 200 can be extended to a position close to the air inlet 110 to save the cost of the pipe. According to actual production verification, extending the second intake pipe 300 to the central position of the reaction chamber 100 can not only improve the diffusion efficiency of the oxygen-containing precursor molecules in the reaction chamber 100 and enhance the diffusion uniformity of the oxygen-containing precursor molecules in the reaction chamber 100 in a short time, but also save production costs.

[0061] In some embodiments, referring to Figure 5 , the reaction chamber 100 has a top side wall and a bottom side wall arranged opposite to each other, and the first spray port 210 is arranged facing the bottom side wall.

[0062] Specifically, in the present embodiment, when the aluminum-containing precursor molecules are introduced into the reaction chamber 100, the aluminum-containing precursor molecules are sprayed toward the bottom side wall of the reaction chamber 100 in the form of a wind curtain through the first spray port 210, and the aluminum-containing precursor molecules can be reflected in a divergent manner through the bottom side wall of the reaction chamber 100. Through repeated reflection, the aluminum-containing precursor molecules will form a dense spray network, so that the aluminum-containing precursor molecules can be evenly diffused throughout the reaction chamber 100, so that the aluminum-containing precursor molecules can be evenly distributed throughout the reaction chamber 100 and react with the surface position of the silicon wafer to form a uniform film layer on the surface of the silicon wafer, thereby improving the conversion efficiency of the solar cell.

[0063] In some embodiments, reference Figure 6 and Figure 7 The reaction chamber 100 has a top side wall and a bottom side wall that are arranged opposite to each other, and the reaction chamber 100 has a sealing side wall that is arranged opposite to the air inlet 110, the second spray port 310 is arranged toward the top side wall, and the third spray port 320 is arranged toward the sealing side wall.

[0064] Specifically, in this embodiment, when the oxygen-containing precursor molecules are introduced into the reaction chamber 100, the oxygen-containing precursor molecules are sprayed toward the top side wall of the reaction chamber 100 in the form of a wind curtain through the second spray port 310. The oxygen-containing precursor molecules can be reflected in a divergent manner through the top side wall of the reaction chamber 100. Through repeated reflections, the oxygen-containing precursor molecules form a dense spray network, so that the oxygen-containing precursor molecules can be evenly diffused throughout the reaction chamber 100. At the same time, through the third spray port 320, the oxygen-containing precursor molecules can be evenly diffused toward the furnace tail end of the reaction chamber 100, thereby compensating for the problem of uneven gas distribution at the furnace tail end of the reaction chamber 100, reducing the concentration difference of the reaction gas at the furnace mouth end and the furnace tail end of the reaction chamber 100, so that a relatively uniform aluminum oxide film layer can be formed on the surface of the silicon wafer, which is beneficial to improving the conversion efficiency of the solar cell.

[0065] In some embodiments, reference Figure 4 and Figure 5 The first air inlet pipeline 200 includes a first pipeline 220, a second pipeline 230 and a third pipeline 240. One end of the first pipeline 220 is connected to a first process pipeline 400 for conveying aluminum-containing precursor molecules, one end of the second pipeline 230 is connected to an end of the first pipeline 220 away from the first process pipeline 400, and one end of the third pipeline 240 is connected to an end of the second pipeline 230 away from the first pipeline 220. The second pipeline 230 and the third pipeline 240 form a T-shaped structure, and the first spray port 210 is disposed in the third pipeline 240.

[0066] Specifically, in this embodiment, when the aluminum-containing precursor molecules are introduced into the reaction chamber 100, the aluminum-containing precursor molecules flow in the order of the first process pipeline 400-first pipeline 220-second pipeline 230-third pipeline 240, and flow into the reaction chamber 100 from the first spray port 210 provided on the third pipeline 240. The connection structure of the second pipeline 230 and the third pipeline 240 is designed as a T-shaped structure, which is conducive to preparing the aluminum oxide film layer by ALD (atomic layer deposition) and by CVD (chemical vapor deposition). In the process of preparing an aluminum oxide film layer by ALD (atomic layer deposition), aluminum-containing precursor molecules will undergo an oxidation reaction with oxygen-containing precursor molecules on the surface of the silicon wafer. This reaction time is usually relatively short, only a few seconds. The second air inlet pipe 300 is designed to be longer than the first air inlet pipe 200, and at least two spray ports are opened on the second air inlet pipe 300, which can quickly pass the oxygen-containing precursor molecules into the furnace mouth and the furnace tail of the reaction chamber 100, so that the oxygen-containing precursor molecules can be quickly and evenly dispersed in the reaction chamber 100, thereby compensating for the problem of too large concentration difference between the head and tail ends caused by the aluminum-containing precursor molecules being passed into the reaction chamber 100 using a T-type pipe. In the process of preparing an aluminum oxide film layer by CVD (chemical vapor deposition), the reaction time is usually relatively long, generally about 100s-300s. If the aluminum-containing precursor molecules are introduced into the reaction chamber 100 using an L-shaped pipe, then after one or two minutes, the molecular concentration at the tail of the reaction chamber 100 will be greater than the molecular concentration at the mouth of the reaction chamber 100, which is not conducive to the uniform formation of the aluminum oxide film layer. If the aluminum-containing precursor molecules are introduced into the reaction chamber 100 using a T-shaped pipe, this concentration difference problem can be reduced, so that an aluminum oxide film layer can be uniformly formed on the surface of the silicon wafer.

[0067] In some embodiments, reference Figure 6 and Figure 7 The second air inlet pipeline 300 includes a fourth pipeline 330, a fifth pipeline 340, a sixth pipeline 350 and a seventh pipeline 360. One end of the fourth pipeline 330 is connected to the second process pipeline 500 for transporting oxygen-containing precursor molecules, one end of the fifth pipeline 340 is connected to the end of the fourth pipeline 330 away from the second process pipeline 500, one end of the sixth pipeline 350 is connected to the end of the fifth pipeline 340 away from the fourth pipeline 330, and one end of the seventh pipeline 360 ​​is connected to the end of the sixth pipeline 350 away from the fifth pipeline 340. The fifth pipeline 340, the sixth pipeline 350 and the seventh pipeline 360 ​​form a Z-shaped structure, the second spray port 310 is provided in the sixth pipeline 350, and the third spray port 320 is provided in the seventh pipeline 360.

[0068] Specifically, in this embodiment, when the oxygen-containing precursor molecules are introduced into the reaction chamber 100, the oxygen-containing precursor molecules will flow in the order of the second process pipeline 500-the fourth pipeline 330-the fifth pipeline 340-the sixth pipeline 350-the seventh pipeline 360, and flow into the reaction chamber 100 from the second spray port 310 of the sixth pipeline 350 and the third spray port 320 of the seventh pipeline 360. The connection structure of the fifth pipeline 340, the sixth pipeline 350 and the seventh pipeline 360 ​​is designed to be a Z-shaped structure, and spray ports are provided on the side close to the air inlet 110 and the side away from the air inlet 110. Considering the time, the time for oxygen-containing precursor molecules to enter the reaction chamber 100 is usually relatively short, only 5s-20s. When the oxygen-containing precursor molecules are introduced using the above-mentioned pipeline structure, the oxygen-containing precursor molecules can be diffused at the furnace mouth and the furnace tail of the reaction chamber 100 at the same time, so that the oxygen-containing precursor molecules and the aluminum-containing precursor molecules react more completely. Therefore, designing the second air inlet pipeline 300 into the above-mentioned structure has more time advantages.

[0069] In some embodiments, the apertures of the first spray port 210 , the second spray port 310 , and the third spray port 320 are all 2 mm.

[0070] Specifically, in the present embodiment, aluminum-containing precursor molecules and oxygen-containing precursor molecules are introduced into the reaction chamber 100 in a spraying manner. Compared with a common air intake manner, at the same time, this manner is more conducive to the diffusion of aluminum-containing precursor molecules and oxygen-containing precursor molecules in the reaction chamber 100, thereby facilitating the generation of a dense aluminum oxide film layer with good uniformity on the surface of the silicon wafer.

[0071] Further, in the present embodiment, the aperture of the spray port is designed to be 2 mm. On the one hand, if the aperture of the spray port is designed to be too large, for example, the aperture of the spray port is designed to be 3 mm, 4 mm, 5 mm, etc., the precursor molecules will almost all diffuse out from the spray port close to the air inlet 110, and the precursor molecules will not diffuse out from the spray port away from the air inlet 110. Therefore, this is not conducive to the precursor molecules being uniformly diffused to the head and tail ends of the reaction chamber 100 at the same time. On the other hand, if the aperture of the spray port is designed to be too small, for example, the aperture of the spray port is designed to be 0.5 mm, 1 mm, 1.5 mm, etc., the gas outlet rate of the precursor molecules will be slowed down, resulting in insufficient precursor molecules in the reaction chamber 100 in a short time, affecting the generation rate of the aluminum oxide film layer.

[0072] In some embodiments, reference Figure 2 and Figure 3, a first connection portion 120 is provided at the air inlet 110, a second connection portion 250 is provided on one side of the first intake pipe 200 close to the air inlet 110, and a third connection portion 370 is provided on one side of the second intake pipe 300 close to the air inlet 110. Among them, the second connection portion 250 and the first connection portion 120 are connected by bolts to connect the first intake pipe 200 and the reaction chamber 100 together; the third connection portion 370 and the first connection portion 120 are connected by bolts to connect the second intake pipe 300 and the reaction chamber 100 together.

[0073] Specifically, in this embodiment, the first connection portion 120 can be a flange, and a first threaded hole can be opened on the first connection portion 120, a second threaded hole can be opened on the second connection portion 250, and a third threaded hole can be opened on the third connection portion 370. When connecting the first connection portion 120 and the second connection portion 250, the first threaded hole and the second threaded hole can be aligned first, and the first connection portion 120 and the second connection portion 250 can be tightened by bolts passing through the first threaded hole and the second threaded hole in sequence to achieve a tight connection between the first intake pipe 200 and the reaction chamber 100. Similarly, when connecting the first connection portion 120 and the third connection portion 370, the first threaded hole and the third threaded hole can be aligned first, and the first connection portion 120 and the third connection portion 370 can be tightened by bolts passing through the first threaded hole and the third threaded hole in sequence to achieve a tight connection between the second intake pipe 300 and the reaction chamber 100.

[0074] In some embodiments, referring to Figure 5 , Figure 6 and Figure 7 , the first intake pipe 200 is provided with at least two first spray nozzles 210; the second intake pipe 300 is provided with at least two second spray nozzles 310. Exemplarily, for example, the first intake pipe 200 can be provided with six first spray nozzles 210; the second intake pipe 300 can be provided with three second spray nozzles 310; the second intake pipe 300 can be provided with one third spray nozzle 320. By providing a plurality of spray nozzles on the intake pipe, it is beneficial to increase the diffusion rate of precursor molecules into the reaction chamber 100, thereby facilitating the improvement of the efficiency of forming an alumina film layer on the surface of the silicon wafer.

[0075] In some embodiments, an embodiment comparison experiment on whether to adopt this intake structure is carried out, referring to

[0076] Table 1 and Table 2:

[0077]

[0078] Table 1

[0079]

[0080] Table 2

[0081] Among them, Table 1 is the alumina film thickness data before and after replacing the intake structure of different furnace tubes on the same machine; Table 2 is the alumina film thickness data before and after replacing the intake structure of the same furnace tube on the same machine. In Table 1 and Table 2, the outer boat blade is at the position close to the side wall of the reaction chamber; the inner boat blade is at the center position of the reaction chamber; positions 1 slot - 12 slots are the positions from the furnace mouth to the furnace tail of the reaction chamber; the film thickness center is the film thickness at the center point of the silicon wafer; film thickness 1 - film thickness 4 are the film thicknesses at the four corners of the silicon wafer; the within-wafer average is the average film thickness of five points on one silicon wafer; the between-wafers average is the average of the film thickness data of all test wafers; the inner and outer page average is the average of the film thickness data measured on the corresponding boat blade; the within-wafer uniformity is the manifestation of the fluctuation of the film thickness data of five points on one silicon wafer. The larger the percentage fluctuation, the more uneven the film thickness of the silicon wafer, that is, the greater the difference in the film thickness data of one silicon wafer. The smaller the percentage fluctuation, the more uniform the film thickness of the silicon wafer, that is, the better the uniformity of the reaction gas diffusion at the position where the silicon wafer is located; the between-wafers uniformity is the difference between the film thickness data of the silicon wafers. The larger the percentage, the more uneven the distribution of the reaction gas between the corresponding positions. The smaller the percentage, the more uniform the distribution of the reaction gas between the corresponding positions; the front boat film thickness is the film thickness data of the silicon wafers from slot 1 to slot 6 (the front boat is at the position close to the furnace mouth of the reaction chamber); the rear boat film thickness is the film thickness data of the silicon wafers from slot 7 to slot 12 (the rear boat is at the position close to the furnace tail of the reaction chamber) (the inner and outer boats only represent the positions of the silicon wafers relative to the center line distance from the reaction chamber); the larger the percentage corresponding to the front boat uniformity, the more uneven the gas distribution at the corresponding furnace mouth. The smaller the percentage corresponding to the front boat uniformity, the more uniform the gas distribution at the corresponding furnace mouth; the larger the percentage corresponding to the rear boat uniformity, the more uneven the gas distribution at the corresponding furnace tail. The smaller the percentage corresponding to the rear boat uniformity, the more uniform the gas distribution at the corresponding furnace tail; the smaller the numerical difference between the front boat uniformity and the rear boat uniformity, the more uniform the gas distribution at the furnace mouth and the furnace tail.

[0082] It can be seen from Table 1 and Table 2 that after adopting the present intake structure, the overall coating uniformity of the silicon wafer will be improved, which is beneficial to improving the conversion efficiency of the solar cell. Through the intake structure provided by this embodiment, the film thickness difference between the furnace mouth and the furnace tail of the alumina film thickness can be reduced from 0.4 nm - 1 nm to 0.3 nm (the difference between the front boat film thickness and the rear boat film thickness) and below, greatly improving the uniformity and denseness of the alumina film thickness. Furthermore, the conversion efficiency of the solar cell is increased by about 0.12% compared with the original intake method.

[0083] Correspondingly, another embodiment of the present invention also provides a solar cell coating device, which includes the intake structure in any of the above embodiments.

[0084] Specifically, in this embodiment, the solar cell coating equipment applying the above intake structure is beneficial to improving the coating uniformity of the solar cell, and thus is beneficial to improving the conversion efficiency of the solar cell.

[0085] Thanks to the improvement of the above intake structure, the solar cell coating equipment of this embodiment has the same technical effects as the above intake structure, which will not be elaborated here.

[0086] It should be noted that for other contents of the intake structure and the solar cell coating equipment disclosed in the present invention, reference can be made to the prior art, which will not be elaborated here.

[0087] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structural transformation made under the inventive concept of the present invention by using the content of the specification and drawings of the present invention, or any direct / indirect application in other related technical fields is included in the patent protection scope of the present invention.

Claims

1. Air intake structure, characterized in that: The air inlet structure is used to connect the reaction chamber to form an aluminum oxide film on the surface of the silicon wafer in the reaction chamber, and the air inlet structure includes: A first air inlet pipeline, the first air inlet pipeline extends from the air inlet to the interior of the reaction chamber, the first air inlet pipeline is provided with a first spray port, and the first air inlet pipeline is used to transport aluminum-containing precursor molecules; a second air inlet pipeline, the second air inlet pipeline extending from the air inlet to the interior of the reaction chamber, the second air inlet pipeline being provided with a second spray port and a third spray port at intervals, the second spray port being provided at a side of the second air inlet pipeline close to the air inlet, the third spray port being provided at a side of the second air inlet pipeline away from the air inlet, the second air inlet pipeline being used for transporting oxygen-containing precursor molecules; Wherein, an extension length of the first air inlet pipeline in the reaction chamber is shorter than an extension length of the second air inlet pipeline in the reaction chamber.

2. The air intake structure according to claim 1, characterized in that: Along the length direction of the reaction chamber, the first air inlet pipe extends to a position close to the air inlet, and the second air inlet pipe extends to a central position of the reaction chamber.

3. The air intake structure according to claim 1, characterized in that: The reaction chamber has a top side wall and a bottom side wall which are arranged opposite to each other, and the first spray port is arranged toward the bottom side wall.

4. The air intake structure according to claim 1, characterized in that: The reaction chamber has a top side wall and a bottom side wall which are arranged opposite to each other, and a sealing side wall which is arranged opposite to the air inlet. The second spray port is arranged toward the top side wall, and the third spray port is arranged toward the sealing side wall.

5. The air intake structure according to claim 1, characterized in that: The first air intake duct comprises: a first pipeline, one end of which is connected to a first process pipeline for transporting the aluminum-containing precursor molecules; a second pipeline, one end of the second pipeline being connected to an end of the first pipeline away from the first process pipeline; a third pipeline, one end of the third pipeline being connected to an end of the second pipeline away from the first pipeline; The second pipeline and the third pipeline form a T-shaped structure, and the first spray port is arranged in the third pipeline.

6. The air intake structure according to claim 1, characterized in that: The second air intake duct comprises: a fourth pipeline, one end of which is connected to a second process pipeline for conveying the oxygen-containing precursor molecules; a fifth pipeline, one end of the fifth pipeline being connected to an end of the fourth pipeline away from the second process pipeline; a sixth pipeline, one end of which is connected to an end of the fifth pipeline away from the fourth pipeline; a seventh pipeline, one end of which is connected to an end of the sixth pipeline away from the fifth pipeline; The fifth pipeline, the sixth pipeline and the seventh pipeline form a Z-shaped structure, the second spray port is arranged in the sixth pipeline, and the third spray port is arranged in the seventh pipeline.

7. The air intake structure according to claim 1, characterized in that: The apertures of the first spray port, the second spray port, and the third spray port are all 2 mm.

8. The air intake structure according to claim 1, characterized in that: A first connection portion is provided at the air inlet, a second connection portion is provided on a side of the first air inlet duct close to the air inlet, and a third connection portion is provided on a side of the second air inlet duct close to the air inlet; The second connection part and the first connection part are connected by bolts to connect the first air intake pipe and the reaction chamber together; the third connection part and the first connection part are connected by bolts to connect the second air intake pipe and the reaction chamber together.

9. The air intake structure according to claim 1, characterized in that: The first air intake duct is provided with at least two of the first spray openings; the second air intake duct is provided with at least two of the second spray openings.

10. Solar cell coating equipment, characterized in that: The invention comprises the air intake structure according to any one of claims 1 to 9.

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