A pipe type PECVD equipment spray inlet device

Abstract

This invention discloses a spray air intake device for a tubular PECVD equipment, comprising a reaction chamber, and an air intake spray plate, a graphite boat, and an exhaust plate disposed within the reaction chamber. The air intake spray plate and the exhaust plate are respectively installed above and below the graphite boat, or respectively installed below and above the graphite boat. The air intake end of the air intake spray plate extends to the outside of the furnace opening and the outside of the furnace tail of the reaction chamber. The front end of the reaction chamber is provided with a furnace door flange, and the rear end of the reaction chamber is provided with a furnace tail flange, which has multiple exhaust ports. During the process, the process gas is transported into the reaction chamber through the air intake spray plate, flows downward through the graphite boat, enters the exhaust plate, and is finally discharged through the exhaust ports on the furnace tail flange. This invention features a compact structure, convenient operation, high safety, and high gas distribution uniformity, effectively reducing the waste of process gas.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic cell manufacturing technology, specifically to a spray air inlet device for tubular PECVD equipment. Background Technology

[0002] Currently, tubular plasma-enhanced chemical vapor deposition (PECVD) equipment is the core equipment for fabricating key structures of mainstream solar cells (emitter-and-back passivated cells (PERC), tunnel oxide passivated contact cells (TOPCon), and various back contact cells (XBC)). However, the currently commonly used furnace inlet and tail exhaust methods result in low process gas utilization and poor silicon wafer film uniformity. Therefore, it is necessary to improve and optimize the process gas venting method of current tubular PECVD equipment to achieve the goal of "cost reduction and efficiency improvement".

[0003] Currently, the common venting method used in tubular PECVD equipment is as follows: process gas first enters the chamber through an annular or "Y"-shaped inlet pipe installed at the furnace opening, and then undergoes dissociation and film formation when passing through a graphite boat placed in the furnace. Finally, the unformed gas and waste gas are discharged through the exhaust port on the furnace tail flange. Because the entire graphite boat is very long (approximately 1.5 meters) and the blades are densely arranged, this gas venting method brings the following problems: (1) When the process gas flows through the graphite boat, it will experience huge flow resistance, which will reduce the proportion of it entering the boat. Most of it will be discharged directly from the cavity without reacting to form a film, resulting in waste.

[0004] (2) The graphite boat is too long in the axial direction, which causes the gas to form a concentration difference along the axial direction in the boat. The gas concentration is high at the bow and the process gas concentration is lower towards the stern, but the proportion of waste gas increases. This not only affects the deposition rate but also causes differences in the thin film structure, resulting in different refractive indices of silicon wafers before and after the boat.

[0005] (3) To improve the uniformity of gas distribution inside the boat, the common practice is to extend a long gas supply pipe (a long metal pipe with an outlet) from the tail or mouth of the furnace to the corresponding position on the boat for targeted gas supply. However, this gas supply method has poor precision in controlling gas uniformity and still has the problem of a large amount of gas wastage.

[0006] Therefore, to address the above problems, it is necessary to design a gas venting method that can effectively improve gas utilization and the uniformity of gas flow within the graphite boat. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to address the problem of large amount of gas waste and uneven distribution in the prior art, and to provide a tubular PECVD equipment spray air inlet device that is compact in structure, easy to disassemble and assemble, and conducive to improving the uniformity of gas distribution.

[0008] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A tubular PECVD equipment spray air intake device includes a reaction chamber, and an air intake spray plate, a graphite boat, and an exhaust plate disposed within the reaction chamber. The air intake spray plate and the exhaust plate are respectively installed above and below the graphite boat, or respectively installed below and above the graphite boat. The air intake end of the air intake spray plate extends to the outside of the furnace opening and the outside of the furnace tail of the reaction chamber. The front end of the reaction chamber is provided with a furnace door flange, and the rear end of the reaction chamber is provided with a furnace tail flange, which has multiple exhaust ports. During the process, the process gas is transported into the reaction chamber through the air intake spray plate, flows downward through the graphite boat, enters the exhaust plate, and is finally discharged through the exhaust ports on the furnace tail flange.

[0009] As a further improvement of the present invention, the air inlet spray plate includes an air equalization chamber, and an inlet air pipe and a rear air inlet air pipe are respectively provided on the top two sides of the air equalization chamber. Multiple inlet air pipes extend to the outside of the furnace mouth of the reaction chamber, and multiple rear air inlet air pipes extend to the outside of the furnace tail of the reaction chamber. An outer air equalization plate is provided at the bottom of the air equalization chamber, and multiple spray holes are evenly distributed on the outer air equalization plate.

[0010] As a further improvement of the present invention, the gas equalization chamber is further provided with an inner gas equalization plate, and the inner gas equalization plate is evenly distributed with multiple spray holes, and the inner gas equalization plate divides the gas equalization chamber into a double-layer gas equalization chamber.

[0011] As a further improvement of the present invention, the spray holes on the inner air distribution plate and the spray holes on the outer air distribution plate are arranged alternately.

[0012] As a further improvement of the present invention, a support arm is provided at the top of the gas equalization chamber, and a fixing seat is provided at both ends of the support arm to realize the connection and fixation of the support arm with the furnace door flange and the furnace tail flange.

[0013] As a further improvement of the present invention, a support frame is provided on the side of the support arm, the support frame being used to support the front air pipe and the rear air pipe.

[0014] As a further improvement of the present invention, each inlet air pipe and each outlet air pipe is individually connected to a mass flow meter to achieve independent control of the intake air volume.

[0015] As a further improvement of the present invention, the furnace tail flange is provided with a main exhaust port and an auxiliary exhaust port. The main exhaust port is located in the middle of the furnace tail flange, the auxiliary exhaust port is located in the lower part of the furnace tail flange, and the exhaust plate is located between the main exhaust port and the auxiliary exhaust port. The main exhaust port is used for vacuuming, and the auxiliary exhaust port is used for exhausting.

[0016] As a further improvement of the present invention, the diameter of the main air extraction port is larger than the diameter of the auxiliary air extraction port.

[0017] As a further improvement of the present invention, the exhaust plate is provided with multiple rows of ventilation holes in the middle to form an exhaust area, and the graphite boat is located directly above the exhaust area.

[0018] Compared with the prior art, the advantages of the present invention are as follows: The tubular PECVD equipment spray air intake device of the present invention, by placing the air intake spray plate and the exhaust plate above and below the graphite boat, or below and above the graphite boat, respectively, allows the process gas to flow out uniformly from directly above or below the graphite boat, while the waste gas is uniformly drawn away and discharged from directly below or above the graphite boat. This ventilation and exhaust method not only significantly shortens the path length of the gas in the chamber, confining the gas mainly within the graphite boat and improving gas utilization, but also solves the problem of uneven distribution of process gas within the boat. Furthermore, by using multiple air intake pipes with outlets distributed at different positions within the gas equalization chamber and whose airflow can be independently controlled, the uniformity of airflow can be further regulated, improving gas utilization. Attached Figure Description

[0019] Figure 1 This is a schematic diagram illustrating the structural principle of the spray air intake device for a tubular PECVD equipment in a specific embodiment of the present invention; Figure 2 This is a schematic diagram of the structural principle of the spray air intake device of the tubular PECVD equipment from another perspective in a specific embodiment of the present invention; Figure 3 This is a schematic diagram of the structure and principle of the spray air inlet plate in a specific embodiment of the present invention; wherein, Figure (a) is a back view and Figure (b) is a bottom view; Figure 4 This is a schematic diagram of the structural principle of a partial cross-section of the spray air inlet plate in a specific embodiment of the present invention; Figure 5 This is a schematic diagram illustrating the structural principle of the exhaust plate in a specific embodiment of the present invention.

[0020] Legend: 1. Inlet spray plate; 2. Graphite boat; 3. Reaction chamber; 4. Furnace door flange; 5. Furnace tail flange; 6. Exhaust plate; 11. Gas equalization chamber; 12. Support arm; 13. Fixing base; 14. Inlet air pipe; 15. Rear air pipe; 16. Support frame; 17. Inner gas equalization plate; 18. Outer gas equalization plate; 19. Spray hole; 51. Main exhaust port; 52. Auxiliary exhaust port; 61. Vent hole. Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings and specific preferred embodiments, but this does not limit the scope of protection of the present invention.

[0022] In the description of this invention, it should be understood that the terms "side", "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0023] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more unless otherwise explicitly specified.

[0024] Example like Figure 1 and Figure 2 As shown, the tubular PECVD equipment spray air intake device of the present invention includes a reaction chamber 3, and an air intake spray plate 1, a graphite boat 2, and an exhaust plate 6 disposed within the reaction chamber 3. The air intake spray plate 1 and the exhaust plate 6 are respectively installed directly above and below the graphite boat 2. The air intake end of the air intake spray plate 1 extends to the outside of the furnace opening and the outside of the furnace tail of the reaction chamber 3, respectively. The front end of the reaction chamber 3 is provided with a furnace door flange 4, and the rear end of the reaction chamber 3 is provided with a furnace tail flange 5, which has multiple exhaust ports. During the process, the process gas is uniformly transported into the reaction chamber 3 through the air intake spray plate 1, flows downward through the graphite boat 2, enters the exhaust plate 6, and is finally discharged through the exhaust ports on the furnace tail flange 5. The gas is sprayed from the top of the graphite boat 2 and uniformly exhausted from the bottom of the graphite boat 2, changing the gas flow path from along the longest side of the graphite boat 2 to along the shortest side of the graphite boat 2, thereby improving the utilization rate of the process gas in the tubular PECVD equipment.

[0025] In other embodiments, the air intake spray plate 1 and the exhaust plate 6 can also be installed directly below and above the graphite boat 2, respectively, which can also achieve the effect of uniform air intake and exhaust.

[0026] like Figure 3As shown, the gas inlet spray plate 1 includes a gas equalization chamber 11, and the area of ​​the gas equalization chamber 11 is slightly larger than the projected area of ​​the graphite boat 2 on it, to ensure that the process gas completely covers the graphite boat 2. Four air inlets are respectively provided on both sides of the top of the gas equalization chamber 11. The four air inlets on one side are connected to four forward air inlets 14, and the four air inlets on the other side are connected to four rear air inlets 15. The four forward air inlets 14 extend to the outside of the furnace opening of the reaction chamber 3, and the four rear air inlets 15 extend to the outside of the furnace tail of the reaction chamber 3, so as to realize the delivery of external process gas to the gas inlet spray plate 1. An outer gas equalization plate 18 is provided at the bottom of the gas equalization chamber 11, and multiple spray holes 19 are evenly distributed on the outer gas equalization plate 18. After the process gas enters the gas inlet spray plate 1, it is then evenly sprayed into the reaction chamber 3 by the outer gas equalization plate 18.

[0027] Furthermore, the four forward air pipes 14 and the four rear air pipes 15 are each individually connected to a mass flow meter to achieve independent control of the air intake, thereby enabling fine regulation of film uniformity.

[0028] like Figure 4 As shown, the gas equalization chamber 11 is also provided with an inner gas equalization plate 17, and multiple spray holes 19 are evenly distributed on the inner gas equalization plate 17. The inner gas equalization plate 17 divides the interior of the gas equalization chamber 11 into a double-layer gas equalization chamber to increase the flow time of the process gas in the gas equalization chamber 11 and improve the uniformity of gas distribution.

[0029] When the gas enters the gas equalization chamber 11, it first undergoes coarse equalization through the inner equalization plate 17, which is covered with spray holes 19, and then enters the graphite boat 2 directly below it through the outer equalization plate 18, which is also covered with spray holes 19. The spray holes 19 on the inner equalization plate 17 and the outer equalization plate 18 are staggered to avoid affecting the equalization effect. By adopting a multi-stage equalization design, the distribution of process gas can be effectively made more uniform. This solves the problem of a small proportion of process gas entering the graphite boat 2 and uneven distribution under traditional gas intake methods.

[0030] like Figure 3 As shown, two support arms 12 are symmetrically arranged on the top of the gas equalization chamber 11 to support the weight of the air inlet spray plate 1. The two ends of the support arms 12 are respectively provided with fixing seats 13 to realize the connection and fixation of the support arms 12 to the furnace door flange 4 and the furnace tail flange 5.

[0031] Furthermore, the inner side of the support arm 12 is provided with multiple support frames 16, which are used to support the front air pipe 14 and the rear air pipe 15 to prevent the front air pipe 14 and the rear air pipe 15 from falling or shifting.

[0032] like Figure 2As shown, the tail flange 5 has one main exhaust port 51 and two auxiliary exhaust ports 52, with the diameter of the main exhaust port 51 being larger than that of the auxiliary exhaust ports 52. The main exhaust port 51 is located in the middle of the tail flange 5, and the auxiliary exhaust ports 52 are located at the lower part of the tail flange 5. The exhaust plate 6 is located between the main exhaust port 51 and the auxiliary exhaust ports 52. During the evacuation phase, the main exhaust port 51, together with the auxiliary exhaust ports 52, discharges impurities from the reaction chamber 3, allowing the chamber to quickly reach a vacuum state. When the deposition process begins, the main exhaust port 51 is closed, leaving only the auxiliary exhaust ports 52 for evacuation.

[0033] like Figure 1 and Figure 5 As shown, the length of the exhaust plate 6 is approximately equal to the length of the entire reaction chamber 3. The two ends of the exhaust plate 6 are close to the furnace opening 4 and the furnace tail flange 5, respectively. Multiple rows of vent holes 61 are provided in the middle of the exhaust plate 6 to form an exhaust zone, with the graphite boat 2 located directly above the exhaust zone. This ensures a consistent gas path from entry to exit from the reaction chamber 3, reducing gas diffusion to other parts of the reaction chamber 3 and thus improving gas utilization. It also enhances the uniformity of process gas distribution within the graphite boat 2. After the process gas enters the graphite boat 2 for film formation, the reaction waste gas and excess process gas first enter the exhaust plate 6 located directly below the graphite boat 2, and then exit the reaction chamber 3 through the auxiliary exhaust port 52 on the furnace tail flange 5.

[0034] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A spray air inlet device for a tubular PECVD equipment, characterized in that, The reaction chamber includes a reaction chamber (3), and an air inlet spray plate (1), a graphite boat (2), and an exhaust plate (6) installed inside the reaction chamber (3). The air inlet spray plate (1) and the exhaust plate (6) are respectively installed above and below the graphite boat (2), or the air inlet spray plate (1) and the exhaust plate (6) are respectively installed below and above the graphite boat (2). The air inlet end of the air inlet spray plate (1) extends to the outside of the furnace mouth and the outside of the furnace tail of the reaction chamber (3). The front end of the reaction chamber (3) is provided with a furnace door flange (4), and the tail end of the reaction chamber (3) is provided with a furnace tail flange (5). The furnace tail flange (5) is provided with multiple exhaust ports. When the process is carried out, the process gas is transported to the reaction chamber (3) through the air inlet spray plate (1), flows downward through the graphite boat (2), and then enters the exhaust plate (6), and finally is discharged from the exhaust port on the furnace tail flange (5).

2. The spray air intake device for tubular PECVD equipment according to claim 1, characterized in that, The air inlet spray plate (1) includes an air equalization chamber (11). The air equalization chamber (11) has multiple air inlets on both sides of its top. Multiple air inlets on one side are connected to multiple forward air pipes (14), and multiple air inlets on the other side are connected to multiple rear air inlets (15). The multiple forward air pipes (14) extend to the outside of the furnace opening of the reaction chamber (3), and the multiple rear air inlets (15) extend to the outside of the furnace tail of the reaction chamber (3). The bottom of the air equalization chamber (11) is provided with an outer air equalization plate (18), and multiple spray holes (19) are evenly distributed on the outer air equalization plate (18).

3. The spray air inlet device for tubular PECVD equipment according to claim 2, characterized in that, The gas equalization chamber (11) is further provided with an inner gas equalization plate (17), and multiple spray holes (19) are evenly distributed on the inner gas equalization plate (17). The inner gas equalization plate (17) divides the interior of the gas equalization chamber (11) into a double-layer gas equalization chamber.

4. The spray air inlet device for tubular PECVD equipment according to claim 3, characterized in that, The spray holes (19) on the inner air distribution plate (17) and the spray holes (19) on the outer air distribution plate (18) are arranged alternately.

5. The spray air inlet device for tubular PECVD equipment according to claim 2, characterized in that, The top of the gas equalization chamber (11) is provided with a support arm (12), and the two ends of the support arm (12) are respectively provided with fixed seats (13) to realize the connection and fixation of the support arm (12) with the furnace door flange (4) and the furnace tail flange (5).

6. The spray air inlet device for tubular PECVD equipment according to claim 5, characterized in that, The support arm (12) is provided with a support frame (16) on its side, which is used to support the front air pipe (14) and the rear air pipe (15).

7. The spray air intake device for tubular PECVD equipment according to any one of claims 2 to 6, characterized in that, Each inlet pipe (14) and each outlet pipe (15) is individually connected to a mass flow meter to achieve independent control of the intake volume.

8. The spray air intake device for tubular PECVD equipment according to any one of claims 1 to 6, characterized in that, The tail flange (5) is provided with a main exhaust port (51) and an auxiliary exhaust port (52). The main exhaust port (51) is located in the middle of the tail flange (5), and the auxiliary exhaust port (52) is located in the lower part of the tail flange (5). The exhaust plate (6) is located between the main exhaust port (51) and the auxiliary exhaust port (52). The main exhaust port (51) is used for vacuuming, and the auxiliary exhaust port (52) is used for exhausting.

9. The spray air inlet device for tubular PECVD equipment according to claim 8, characterized in that, The diameter of the main air extraction port (51) is larger than the diameter of the auxiliary air extraction port (52).

10. The spray air intake device for tubular PECVD equipment according to claim 8, characterized in that, The exhaust plate (6) has multiple rows of ventilation holes (61) in the middle to form an exhaust area, and the graphite boat (2) is located directly above the exhaust area.

Images