CN215856322U

CN215856322U - Special gas pipeline and flat plate type PECVD equipment

Info

Publication number: CN215856322U
Application number: CN202121981904.9U
Authority: CN
Inventors: 张永; 梁立维; 胡明强
Original assignee: Ja Solar Co Ltd
Current assignee: Jingao Solar Co Ltd
Priority date: 2021-08-23
Filing date: 2021-08-23
Publication date: 2022-02-18
Anticipated expiration: 2031-08-23

Abstract

The application belongs to the field of PECVD coating equipment, and particularly relates to a special gas pipeline. The special gas pipeline comprises a flow equalizing pipe and a flow dividing pipe; the flow equalizing pipe is provided with special air holes along the axial direction; the number of the special air holes is trisected, and the special air holes comprise a first end hole positioned at one end part of the flow equalizing pipe, a middle hole positioned in the middle part of the flow equalizing pipe and a second end hole positioned at the other end part of the flow equalizing pipe; the shunt tubes are close to the two end faces of the flow equalizing pipe, and the shunt tubes supply air to the first end holes and the second end holes, wherein the air supply amount of the first end holes and the air supply amount of the second end holes are higher than that of the middle holes. The connecting position of the shunt pipe and the flow equalizing pipe is closer to the first end hole and the second end hole and is further from the middle hole; the air supply amount of the shunt tube at the first end hole and the second end hole is relatively high, and the air supply amount at the middle hole is relatively low, so that the influence of the exhaust hole on the first end hole and the second end hole is balanced, and the film thickness uniformity of the substrate is ensured.

Description

Special gas pipeline and flat plate type PECVD equipment

Technical Field

The application relates to the field of PECVD (plasma enhanced chemical vapor deposition) coating equipment, in particular to a special gas pipeline and flat-plate type PECVD equipment.

Background

In the photovoltaic industry, PECVD coating equipment delivers ammonia gas and silane gas into a reaction chamber through a special gas pipeline, so that the gases react in the reaction chamber and a silicon nitride film is deposited on a substrate. The PECVD coating equipment comprises tubular PECVD equipment and flat-plate PECVD equipment, and the flat-plate PECVD equipment is widely used due to the characteristics of good uniformity and high yield compared with the tubular PECVD equipment.

The flat plate type PECVD equipment comprises a special gas pipeline for conveying gas to the reaction chamber, wherein the special gas pipeline comprises a flow equalizing pipe communicated with the reaction chamber and a gas inlet pipe connected with the flow equalizing pipe. In the conventional flat plate type PECVD equipment, an air inlet pipe is connected with a flow equalizing pipe through at least two flow dividing pipes, special gas is uniformly supplied to the flow equalizing pipe through the flow dividing pipes by the air inlet pipe, and the special gas is conveyed into a reaction chamber by the air supply pipe through the uniformly distributed special gas holes, so that a substrate in the reaction chamber is uniformly coated with a film.

The side wall of the reaction cavity corresponding to the two end faces of the flow equalizing pipe is provided with an exhaust hole, and the exhaust hole exhausts air outwards to maintain the air pressure balance in the reaction cavity. However, the provision of the exhaust holes affects the special gas holes located at both ends of the flow equalizing pipe, and causes a problem that the film thickness at the center of the substrate is high and the film thicknesses at both sides are low. The uneven film thickness of the substrate can lead to poor uniformity of the color of the coated film, and meanwhile, the abnormal phenomenon of black burning of the quartz tube can occur during later maintenance.

Disclosure of Invention

Aiming at the problems, the application provides a special gas pipeline of a flat plate type PECVD device, which reduces the influence of exhaust holes on special gas holes at two end parts of a flow equalizing pipe and improves the uniformity of film thickness by changing the distribution position of a flow dividing pipe relative to the flow equalizing pipe.

A first aspect of the present embodiment provides a special gas pipeline, including a flow equalizing pipe and a flow dividing pipe; the flow equalizing pipe is provided with special air holes along the axial direction;

the special gas hole comprises a first end hole positioned at one end part of the flow equalizing pipe, a middle hole positioned in the middle of the flow equalizing pipe and a second end hole positioned at the other end part of the flow equalizing pipe;

the shunt tubes are close to the two end faces of the flow equalizing pipe, and the shunt tubes supply air to the first end holes and the second end holes, wherein the air supply amount of the first end holes and the air supply amount of the second end holes are higher than that of the middle holes.

Preferably, the number of the special air holes is trisected, and the number of the shunt tubes is two; the distance between the connecting position of the two shunt tubes and the corresponding end face of the flow equalizing tube is 1/8-2/7 of the length of the flow equalizing tube.

Preferably, the special gas pipeline further comprises an air inlet pipe positioned below the flow equalizing pipe; the air inlet pipe is connected with inlets of the two shunt pipes through a tee joint; the outlet of the shunt pipe is connected to the bottom of the flow equalizing pipe.

Preferably, the shunt tubes and the flow equalizing tubes are fixedly connected in a welding mode.

Preferably, a nut for fixing is further arranged on the flow equalizing pipe.

In a second aspect of the present embodiment, a flat plate type PECVD apparatus is provided, which comprises the special gas pipeline.

The technical scheme of this application has changed the shunt tubes and has flow equalized the relative position of pipe, through improving the gas supply volume of shunt tubes to first end hole and second end hole to the influence of balanced exhaust hole to first end hole and second end hole, thereby guarantee that the membrane of substrate is thick even. The flow dividing pipe is arranged close to two end faces of the air supply pipe, and the connecting position of the flow dividing pipe and the flow equalizing pipe is closer to the first end hole and the second end hole and is further from the middle hole; the gas supply volume of shunt tubes in first tip hole and second tip hole department is higher relatively, and the gas supply volume in middle part hole department is lower relatively to the influence of balanced exhaust hole to first tip hole and second tip hole improves the relatively poor problem of homogeneity of coating film colour, avoids the quartz capsule to appear burning black abnormal phenomenon when later stage is maintained.

Drawings

Fig. 1 is a schematic structural diagram of a special gas pipeline.

In the figure, an air inlet pipe 1, a shunt pipe 2, a flow equalizing pipe 3, a special air hole 4, a first end hole 41, a middle hole 42, a second end hole 43, a three-way joint 5 and a nut 6.

Detailed Description

The following is further detailed by the specific embodiments:

interpretation of terms:

PECVD: is abbreviated as Plasma Enhanced Chemical Vapor Deposition (PECVD). PECVD is a process in which a gas containing atoms constituting a thin film is ionized by microwaves to locally form plasma, which is very chemically active and easily reacts to deposit a desired thin film on a substrate. Special qi: SiH introduced in PECVD₄And NH₃A gas.

The embodiment provides a special gas pipeline of a flat plate type PECVD device, which comprises a gas inlet pipe 1, a shunt pipe 2 and a flow equalizing pipe 3 which are sequentially connected. In this embodiment, the tube wall of the flow equalizing tube 3 is provided with special gas holes 4 which are uniformly distributed along the axial direction, and the special gas in the flow equalizing tube 3 enters the reaction chamber through the special gas holes 4.

In the present embodiment, the number of the special air holes 4 is trisected, and the special air holes include a first end hole 41, a middle hole 42 and a second end hole 43 which are sequentially distributed from one end of the flow equalizing pipe 3. The first end openings are distributed at one end of the flow straightener 3, the central opening 42 is distributed in the middle of the flow straightener 3, and the second end openings 43 are distributed at the second end of the flow straightener 3. It should be noted that trisection in the present embodiment means that the first end hole 41, the middle hole 42, and the second end hole 43 have the same number of small holes. The reaction chamber is the portion of the flat plate PECVD apparatus used to deposit the silicon nitride film.

In the present embodiment, the air inlet pipe 1 is located below the flow equalizing pipe 3, and the special air hole 4 is opened at the top of the flow equalizing pipe 3. Air supply equipment is connected to the air inlet of intake pipe 1, and the gas outlet of intake pipe 1 and the access connection of shunt tubes 2, the exit linkage of shunt tubes 2 are to the bottom of flow equalizing pipe 3.

The special gas firstly enters the gas inlet pipe 1 from the gas supply equipment, then is shunted to the flow equalizing pipe 3 through the shunt pipe 2, and finally is conveyed to the reaction chamber through the special gas hole 4 on the flow equalizing pipe 3. The shunt pipes 2 can dispersedly supply the special gas in the gas inlet pipe 1 to different parts of the flow equalizing pipe 3, so that the special gas holes 4 at different parts have relatively balanced gas supply quantity, the thickness of the film deposited on the substrate is ensured to be consistent as much as possible, and the film coating quality of the substrate is improved.

Because the reaction chamber has been seted up the exhaust hole for on the lateral wall at flow equalizing pipe 3 both ends, the in-process of special gas is carried to special gas hole 4 toward the reaction chamber in, and the reaction chamber needs utilize the exhaust hole outwards to bleed to the inside atmospheric pressure of balanced reaction chamber. In the conventional special gas pipeline, the design of the shunt pipe 2 only considers the gas supply amount of each special gas hole 4, neglects the influence of the gas discharge hole on the first end hole 41 and the second end hole 43, and thus causes the film thickness of the substrate to be inconsistent. The exhaust holes directly extract part of the special gas delivered by the first end holes 41 and the second end holes 43, so that part of the special gas supplied by the first end holes 41 and the second end holes 43 cannot react and is deposited on the substrate, and the film thickness of the corresponding middle holes 42 of the substrate is higher than that of the first end holes 41 and the second end holes 43 of the substrate.

The embodiment changes the relative positions of the shunt tubes 2 and the flow equalizing tubes 3, and the air supply quantity of the shunt tubes 2 to the first end holes 41 and the second end holes 43 is improved, so that the influence of the exhaust holes on the first end holes 41 and the second end holes 43 is balanced, and the film thickness of the substrate is ensured to be uniform. In the embodiment, the shunt tubes 2 are arranged close to two end faces of the gas supply pipe, the connection positions of the shunt tubes 2 and the flow equalizing pipes 3 are closer to the first end holes 41 and the second end holes 43 and are further from the middle holes 42; the air supply amount of the shunt tube 2 is relatively high at the first and second end holes 41 and 43 and relatively low at the center hole 42, thereby balancing the influence of the exhaust holes on the first and second end holes 41 and 43.

Specifically, the special gas pipeline in this embodiment has two shunt tubes 2, the gas outlet of the gas inlet pipe 1 is connected with the inlets of the two shunt tubes 2 through a three-way joint 5, and the outlets of the two shunt tubes 2 are fixed with the flow equalizing pipe 3 in a welded manner, so as to ensure good gas tightness and no gas leakage. The distance between the fixed positions of the two shunt tubes 2 and the two corresponding end faces of the flow equalizing tube 3 is 1/8-2/7 of the length of the flow equalizing tube 3, such as 1/7, 1/6, 1/5, 1/4, 2/9, 2/11 and 3/11.

As shown in fig. 1, 24 special air holes 4 are uniformly formed in the air equalizing pipe, the distance between the special air holes 4 is 50mm, and the sizes of the special air holes 4 are consistent. It should be noted that, because the distance between the two outermost special air holes 4 and the corresponding end face of the flow equalizing pipe 3 is relatively short, the length of the flow equalizing pipe 3 in this embodiment can be regarded as the distance between the two outermost special air holes 4. In the embodiment, the distance between the outlets of the two shunt tubes 2 is about 700mm, and the distance between the outlets of the two shunt tubes 2 and the two end faces of the corresponding flow equalizing tube 3 is about 250 mm. And 4 nuts 6 for fixing the special gas pipeline are also arranged on the flow equalizing pipe 3.

The number of the shunt tubes 2 includes, but is not limited to, two shunt tubes 2 mentioned in the present application, and other numbers such as 4

shunt tubes

2, 5 shunt tubes and the like may be provided according to the air supply amount of the entire flow equalizing tube 3 and the air exhaust amount of the exhaust hole.

The application is not limited solely to the description and embodiments, and additional advantages and modifications will readily occur to those skilled in the art, so that the application is not limited to the specific details, representative apparatus, and illustrative examples shown and described herein, without departing from the spirit and scope of the general concept as defined by the appended claims and their equivalents.

Claims

1. The special gas pipeline comprises a flow equalizing pipe and a flow dividing pipe, and the flow equalizing pipe is provided with a special gas hole along the axial direction of the flow equalizing pipe; the method is characterized in that:

2. The special gas pipeline of claim 1, wherein: the number of the special air holes is trisected, and the number of the shunt tubes is two; the distance between the connecting position of the two shunt tubes and the corresponding end face of the flow equalizing tube is 1/8-2/7 of the length of the flow equalizing tube.

3. The special gas pipeline of claim 2, wherein: the special gas pipeline also comprises a gas inlet pipe positioned below the flow equalizing pipe; the air inlet pipe is connected with the inlets of the two shunt pipes through a three-way joint, and the outlets of the shunt pipes are connected to the bottoms of the flow equalizing pipes.

4. The special gas pipeline of claim 3, wherein: the flow dividing pipe and the flow equalizing pipe are fixedly connected in a welding mode.

5. The special gas pipeline according to any one of claims 1-4, wherein: and the flow equalizing pipe is also provided with a nut for fixing.

6. A flat plate type PECVD apparatus, characterized in that the apparatus comprises the special gas pipeline of any one of claims 1-5.