Gas inlet mechanism for chemical vapor deposition

Abstract

The utility model relates to a gas inlet mechanism for chemical vapor deposition, which is applied to a quartz tube for chemical vapor deposition, the gas inlet mechanism for chemical vapor deposition comprises at least two groups of gas inlet components distributed on two sides in the quartz tube, and each gas inlet component comprises a plurality of gas inlet tubes with different lengths and two through ends. The gas inlet assemblies are arranged on the two sides in the quartz tube, each gas inlet assembly is provided with a plurality of gas inlet pipes with different lengths, and the gas outlet ends of the gas inlet pipes are located at different positions in the quartz tube, so that silane is introduced into different depths in the quartz tube, and different gas inlet flows can be set for the gas inlet pipes; uniformity of a gas field in the quartz tube can be guaranteed, so that difference of gas density in the quartz tube is reduced, quality of an amorphous silicon film is guaranteed, difference of film thickness in the quartz tube is reduced, arrangement of gas inlet holes in the gas inlet tube is omitted, and service life of the gas inlet tube can be prolonged remarkably. And meanwhile, the influence on field SPC control caused by replacement of the air inlet pipe is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical vapor deposition, in particular to an air intake mechanism used for chemical vapor deposition. Background Art

[0002] The development history of low-pressure chemical vapor deposition (LPCVD) technology can be traced back to the mid-20th century. With the rise and development of the semiconductor industry, LPCVD has gradually become an indispensable part of manufacturing integrated circuits and other microelectronic devices.

[0003] After entering the 21st century, with the rapid development of nanotechnology and microelectronics technology, LPCVD technology continues to face new challenges and opportunities. In advanced semiconductor manufacturing, LPCVD remains one of the key thin film deposition technologies, especially in the manufacture of deep submicron and nanoscale devices, which places higher demands on film thickness control, step coverage, interface quality, etc. At the same time, LPCVD technology has also been expanded to other fields, such as optoelectronic devices, microelectromechanical systems (MEMS), solar cells, etc. In the process of development, LPCVD technology has continuously integrated new scientific theories and engineering innovations, such as the optimization of reaction chamber design, the selection and synthesis of precursor gases, the study of reaction kinetics, and computer simulation, to meet the ever-changing needs of the industry.

[0004] In the current TOPCon and back-contact cell production process, the LPCVD process deposits amorphous silicon films of a certain thickness by introducing silane for thermal decomposition. In this process, two pairs of long stainless steel tubes with air holes are used as inlet pipes for silane at the end of the quartz tube. The processing length of one pair of inlet pipes is 3.7 meters, and the processing length of the other pair of inlet pipes is 2.8 meters. Figure 1 As shown in the figure, for an intake pipe of 3.7 m in length, the air holes on the intake pipe are evenly distributed every 10 cm. Figure 2As shown in the figure, for a 2.8-meter inlet pipe, the air holes on the inlet pipe are evenly distributed every 40 cm from 1.0 meter after the furnace tail. However, LPCVD uses silane to pass through a quartz tube for thermal decomposition and deposition of intrinsic amorphous silicon. As deposition time increases, the thickness of the amorphous silicon deposited on the inner wall of the quartz tube continues to increase. On the one hand, a large amount of amorphous silicon film will be deposited in the inlet pipe, resulting in a smaller inner diameter of the inlet pipe and affecting the silane inlet flow rate. On the other hand, amorphous silicon film will also be deposited on the inner wall of the pores of the inlet pipe. As deposition time continues to increase, the pore diameter of the inlet pipe becomes smaller and even pores become clogged. These two factors seriously affect the uniformity of silane inlet, causing gasping and affecting the quality of the film. When upgrading to back-contact cells, LPCVD is more widely used. For the N / P region emitter prepared in BC, the thickness of the intrinsic silicon film deposited by LPCVD is basically between 250nm and 350nm. This deposition thickness is 2-3 times that of traditional TOPCon. Therefore, with the update of technology, the life of the intake pipe will be reduced to 1 / 3-1 / 2 of the original, increasing non-silicon costs. In addition, after replacing the intake pipe, the adaptation formula needs to be readjusted, which increases on-site rework and has an impact on SPC control. Utility Model Content

[0005] Based on this, in view of the current TOPCon and back contact battery production process, the LPCVD process uses two pairs of long stainless steel tubes with air holes as the silane inlet pipes at the tail of the furnace in the quartz tube. The inner diameter of the quartz tube becomes smaller due to the deposition of amorphous silicon film layer in the quartz tube. At the same time, amorphous silicon film layer will also be deposited in the air holes of the inlet pipe, causing the aperture to become smaller or even blocked, affecting the uniformity of silane intake, causing gasping, affecting the quality of the film, and reducing the service life of the inlet pipe. Technical problems, the utility model proposes an air intake mechanism for chemical vapor deposition.

[0006] The utility model provides an air intake mechanism for chemical vapor deposition, which is applied to a quartz tube for chemical vapor deposition. The air intake mechanism for chemical vapor deposition includes at least two groups of air intake components distributed on both sides of the quartz tube, and each air intake component includes a plurality of air intake pipes of different lengths and through-connected at both ends.

[0007] The utility model arranges air intake components on both sides of the quartz tube, and each air intake component is provided with a plurality of air intake pipes of different lengths. The air outlet ends of the air intake pipes are located at different positions in the quartz tube, so as to introduce silane into the quartz tube at different depths. Different air intake flow rates can be set for each air intake pipe, thereby ensuring the uniformity of the gas field in the quartz tube, thereby reducing the difference in gas density in the quartz tube, thereby ensuring the quality of the amorphous silicon film, reducing the difference in film thickness in the quartz tube, and canceling the air intake hole arrangement on the air intake pipe, which can significantly increase the service life of the air intake pipe, reduce the use cost of the air intake pipe, and reduce the impact of the replacement of the air intake pipe on the on-site SPC control.

[0008] As a further improvement of the above-mentioned scheme of the present invention, in each air intake assembly, several air intake pipes are arranged in sequence from bottom to top along the inner wall of the quartz tube, the air intake ends of the several air intake pipes are in the same vertical plane, and the length of the air intake pipes gradually decreases from bottom to top.

[0009] As a further improvement of the above solution of the present invention, the air intake assembly includes three air intake pipes, the length of the air intake pipe at the bottom is 3.4-3.7m, the length of the air intake pipe in the middle is 2.5-2.7m, and the length of the air intake pipe at the top is 1.8-2.0m.

[0010] As a further improvement of the above solution of the present invention, in each air intake assembly, several air intake pipes have different inner diameters.

[0011] As a further improvement of the above solution of the present invention, in each air intake assembly, a plurality of air intake pipes are sequentially spaced from bottom to top along the inner wall of the quartz tube, and the inner diameter of the air intake pipes gradually decreases from bottom to top.

[0012] As a further improvement of the above solution of the present invention, the air intake assembly includes three air intake pipes, the inner diameter of the air intake pipe at the bottom is 1.2-1.4 cm, the inner diameter of the air intake pipe in the middle is 1.0-1.2 cm, and the inner diameter of the air intake pipe at the top is 0.8-1.0 cm.

[0013] As a further improvement of the above solution of the present invention, in each air intake assembly, several air intake pipes have different outer diameters.

[0014] As a further improvement of the above solution of the present invention, in each air intake assembly, a plurality of air intake pipes are sequentially spaced apart from bottom to top along the inner wall of the quartz tube, and the outer diameter of the air intake pipes gradually decreases from bottom to top.

[0015] As a further improvement of the above-mentioned solution of the present invention, the air intake assembly includes three air intake pipes, the outer diameter of the air intake pipe at the bottom is 1.3-1.5 cm, the outer diameter of the air intake pipe in the middle is 1.1-1.3 cm, and the outer diameter of the air intake pipe at the top is 0.9-1.1 cm.

[0016] As a further improvement of the above-mentioned solution of the present invention, in the air intake assembly, the vertical distance between the air intake pipe at the bottom and the bottom of the quartz tube is 80-100 mm, the vertical distance between the air intake pipe in the middle and the bottom of the quartz tube is 160-180 mm, and the vertical distance between the air intake pipe at the top and the bottom of the quartz tube is 220-240 mm.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. The utility model sets air intake assemblies on both sides of the quartz tube, and each air intake assembly is provided with a plurality of air intake pipes of different lengths. The air outlet ends of the air intake pipes are located at different positions in the quartz tube, so as to introduce silane into the quartz tube at different depths. Different air intake flow rates can be set for each air intake pipe, thereby ensuring the uniformity of the gas field in the quartz tube, thereby reducing the difference in gas density in the quartz tube, thereby ensuring the quality of the amorphous silicon film and reducing the difference in film thickness in the quartz tube. In addition, the air intake hole setting on the air intake pipe is eliminated, which can significantly increase the service life of the air intake pipe, reduce the use cost of the air intake pipe, and reduce the impact of the replacement of the air intake pipe on the on-site SPC control.

[0019] 2. The air intake pipes of the air intake components in the present invention have different inner and outer diameters, so that each air intake pipe has a different air intake flow rate, thereby matching the uniformity of the gas field inside the quartz tube.

[0020] 3. The vertical distance between the air inlet pipe and the bottom of the quartz tube in each air inlet assembly of the present invention is set to further ensure the uniformity of the gas field inside the quartz tube. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the structure of an air inlet pipe with air holes of 3.7 meters in length in the prior art;

[0022] Figure 2 This is a schematic diagram of the structure of an air inlet pipe with air holes of 2.8 meters in length in the prior art;

[0023] Figure 3 A schematic structural diagram of an air intake mechanism for chemical vapor deposition proposed in an embodiment of the present utility model;

[0024] Figure 4 A schematic diagram of the distribution of an air intake mechanism for chemical vapor deposition in a quartz tube proposed in an embodiment of the present utility model;

[0025] Reference numerals: 1, quartz tube; 2, air inlet pipe. DETAILED DESCRIPTION

[0026] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to specific embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to facilitate a more thorough and comprehensive understanding of the disclosure of the present invention.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0028] Reference Figure 3 、 Figure 4 This embodiment proposes an air intake mechanism for chemical vapor deposition, which is applied to a quartz tube 1 for chemical vapor deposition and includes two sets of air intake components.

[0029] Two sets of air inlet assemblies are symmetrically arranged about a diameter of the quartz tube 1. Each air inlet assembly includes three air inlet tubes 2 of varying lengths, each of which is connected at both ends and closely adheres to the inner wall of the quartz tube 1. Of course, in other embodiments, each air inlet assembly may include two, four, or other numbers of air inlet tubes 2. By arranging air inlet assemblies on both sides of the quartz tube 1, each air inlet assembly includes several air inlet tubes 2 of varying lengths, with the outlet ends of the air inlet tubes 2 located at different positions within the quartz tube 1, allowing silane to be introduced to different depths within the quartz tube 1. This allows for different air inlet flow rates to be set for each air inlet tube 2, ensuring uniformity of the gas field within the quartz tube 1 and reducing variations in gas density within the quartz tube 1. This ensures the quality of the amorphous silicon thin film and reduces variations in film thickness within the quartz tube 1. Furthermore, by eliminating the air inlet holes in the air inlet tubes 2, the service life of the air inlet tubes 2 is significantly increased, the cost of the air inlet tubes 2 is reduced, and the impact of air inlet tube 2 replacement on on-site SPC control is minimized.

[0030] In this embodiment, the three air inlet pipes 2 of the air inlet assembly are spaced apart from each other along the inner wall of the quartz tube 1 from bottom to top. The air inlet ends of the three air inlet pipes 2 are located in the same vertical plane and are connected to the silane gas source. The other ends of the three air inlet pipes 2 extend into the quartz tube 1 at different depths. The lengths of the three air inlet pipes 2 of the air inlet assembly gradually decrease from bottom to top. The lengths of the three air inlet pipes 2 in each air inlet assembly can be appropriately designed based on actual conditions. In this embodiment, the length of the bottommost air inlet pipe 2 is 3.4-3.7 meters, the length of the middle air inlet pipe 2 is 2.5-2.7 meters, and the length of the topmost air inlet pipe 2 is 1.8-2.0 meters.

[0031] In this embodiment, the three air inlet pipes 2 of each air inlet assembly have different inner and outer diameters, and the inner and outer diameters of the air inlet pipes 2 gradually decrease from bottom to top. This allows the air inlet pipes 2 to have different intake flow rates, thereby ensuring uniformity of the gas field within the quartz tube 1. The inner diameter of the air inlet pipes 2 of each air inlet assembly can be appropriately set based on actual conditions. In this embodiment, the inner diameter of the air inlet pipe 2 at the bottom is 1.2-1.4 cm, the inner diameter of the air inlet pipe 2 in the middle is 1.0-1.2 cm, and the inner diameter of the air inlet pipe 2 at the top is 0.8-1.0 cm. The outer diameter of the air inlet pipe 2 of each air inlet assembly can be appropriately set based on actual conditions. In this embodiment, the outer diameter of the air inlet pipe 2 at the bottom is 1.3-1.5 cm, the outer diameter of the air inlet pipe 2 in the middle is 1.1-1.3 cm, and the outer diameter of the air inlet pipe 2 at the top is 0.9-1.1 cm. The air inlet pipes 2 of the air inlet components have different inner diameters and outer diameters, so that each air inlet pipe 2 has a different air inlet flow rate, thereby matching the uniformity of the gas field inside the quartz tube 1 .

[0032] In each air intake assembly, the vertical distance between the air intake pipe 2 and the inner bottom of the quartz tube 1 can be appropriately set based on actual conditions. In this embodiment, the vertical distance between the bottommost air intake pipe 2 and the inner bottom of the quartz tube 1 is 80-100 mm, the vertical distance between the middle air intake pipe 2 and the inner bottom of the quartz tube 1 is 160-180 mm, and the vertical distance between the topmost air intake pipe 2 and the inner bottom of the quartz tube 1 is 220-240 mm. The vertical distance between the air intake pipe 2 and the inner bottom of the quartz tube 1 in each air intake assembly further ensures the uniformity of the gas field inside the quartz tube 1.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of this invention are for the purpose of describing specific embodiments only and are not intended to limit this invention. The term "or / and" as used herein includes any and all combinations of one or more of the associated listed items.

[0034] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0035] The above-described embodiments merely represent several implementations of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present utility model patent shall be determined by the appended claims.

Claims

1. A gas inlet mechanism for chemical vapor deposition, which is applied to a quartz tube (1) for chemical vapor deposition, characterized in that: The gas intake mechanism for chemical vapor deposition comprises at least two groups of gas intake components distributed on both sides of a quartz tube (1), and each gas intake component comprises a plurality of gas intake pipes (2) of different lengths and connected at both ends.

2. The gas inlet mechanism for chemical vapor deposition according to claim 1, characterized in that: In each of the air intake assemblies, a plurality of air intake pipes (2) are sequentially spaced from bottom to top along the inner wall of the quartz tube (1), the air intake ends of the plurality of air intake pipes (2) are located in the same vertical plane, and the length of the air intake pipes (2) gradually decreases from bottom to top.

3. The gas inlet mechanism for chemical vapor deposition according to claim 2, characterized in that: The air intake assembly comprises three air intake pipes (2), the length of the air intake pipe (2) at the bottom is 3.4-3.7 m, the length of the air intake pipe (2) at the middle is 2.5-2.7 m, and the length of the air intake pipe (2) at the top is 1.8-2.0 m.

4. The gas inlet mechanism for chemical vapor deposition according to claim 1, characterized in that: In each of the air intake assemblies, the plurality of air intake pipes (2) have different inner diameters.

5. The gas inlet mechanism for chemical vapor deposition according to claim 4, characterized in that: In each of the air intake assemblies, a plurality of air intake pipes (2) are sequentially spaced from bottom to top along the inner wall of the quartz tube (1), and the inner diameter of the air intake pipe (2) gradually decreases from bottom to top.

6. The gas inlet mechanism for chemical vapor deposition according to claim 5, characterized in that: The air intake assembly comprises three air intake pipes (2), wherein the inner diameter of the air intake pipe (2) at the bottom is 1.2-1.4 cm, the inner diameter of the air intake pipe (2) at the middle is 1.0-1.2 cm, and the inner diameter of the air intake pipe (2) at the top is 0.8-1.0 cm.

7. The gas inlet mechanism for chemical vapor deposition according to claim 1, characterized in that: In each of the air intake assemblies, the plurality of air intake pipes (2) have different outer diameters.

8. The gas inlet mechanism for chemical vapor deposition according to claim 7, characterized in that: In each of the air intake assemblies, a plurality of air intake pipes (2) are sequentially spaced from bottom to top along the inner wall of the quartz tube (1), and the outer diameter of the air intake pipe (2) gradually decreases from bottom to top.

9. The gas inlet mechanism for chemical vapor deposition according to claim 7, characterized in that: The air intake assembly comprises three air intake pipes (2), wherein the outer diameter of the air intake pipe (2) at the bottom is 1.3-1.5 cm, the outer diameter of the air intake pipe (2) at the middle is 1.1-1.3 cm, and the outer diameter of the air intake pipe (2) at the top is 0.9-1.1 cm.

10. The gas inlet mechanism for chemical vapor deposition according to claim 3, characterized in that: In the air intake assembly, the vertical distance between the air intake pipe (2) at the bottom and the bottom of the quartz tube (1) is 80-100 mm, the vertical distance between the air intake pipe (2) at the middle and the bottom of the quartz tube (1) is 160-180 mm, and the vertical distance between the air intake pipe (2) at the top and the bottom of the quartz tube (1) is 220-240 mm.

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