TWI493070B - Gas diffusion chamber - Google Patents

Description

Gas diffusion chamber

This invention relates to a gas diffusion chamber, and more particularly to a gas diffusion chamber for depositing a thin film on a substrate.

Chemical vapor deposition (CVD) plays a pivotal role in semiconductor thin film processes, flat panel display (FPD) processes, or solar cell filming processes. Its main function is to pass special reactive gases into the vacuum. In the cavity, the plasma can be used to accelerate the chemical reaction of the gas to deposit a thin film on the surface of the substrate. In the CVD process parameters, the cavity flow field is one of the key factors affecting the coating result.

Taiwan Bulletin No. TW 405026 proposes a gas diffuser for the manufacture of a semiconductor device and a reactor having the same. The diffuser is presented in the form of a gas-tight cylinder, wherein a hollow portion is formed and an upwardly opening air inlet is provided to allow gas to flow into the hollow portion, and a disc-shaped diffusion plate is disposed on the bottom side thereof with a plurality of nozzles for guiding And controlling the outflow of the gas into the hollow portion, where the diffusion plate increases in thickness from the center in the radial direction, so that the length of the nozzle through which the gas passes increases as the distance from the center of the diffusion plate increases in the radial direction. Since the distance between the nozzle outlet and the wafer is shortened, it can be kept constant or increased as the gas injection speed of the nozzle outlet increases.

Taiwan Publication No. TW M299917 proposes a gas distribution plate assembly for a plasma processing chamber having a cover plate, comprising: a diffusion plate having: an upstream side, a downstream side facing the treatment zone, and a plurality of gas passages Passing through the diffuser plate; and a baffle disposed between the cover plate of the process chamber and the diffuser plate, having a plurality of holes extending from the surface of the baffle to the lower surface, wherein the holes have at least two sides. The holes of the baffle are divided into small pinholes and large pinholes for allowing passage of a sufficient gas mixture for improving the uniformity of processing of the entire substrate.

Taiwan Application No. TW 201134979 proposes a gas distribution spray module that allows the gas to be sufficiently mixed to solve the non-uniformity of the gas sprayed onto the substrate, through a gas distribution spray module of a coating device, including the first and second, The third and fourth diffusing plates can bring the distance between the gas distribution spray module and the substrate closer, and increase the coating efficiency.

However, the air intake methods of the above three patents all adopt the vertical air intake mode, but the biggest problem of this method is that after the gas is introduced into the cavity, it is usually immediately taken away by the exhausting area around the four, and A local stagnant zone is formed at the center farthest from the pumping zone, and the film thickness tends to be relatively thicker or thinner than the average value at the time of film formation, so that the film is unevenly distributed at the center of the substrate and around the substrate. Type. Therefore, the gas inlet mode and the flow channel geometry of the gas flow are such that the chemical vapor deposition cannot be effectively distributed uniformly on the film formation substrate, and the uneven distribution of the gas flow is a fundamental problem.

Therefore, there is a need to provide a gas diffusion chamber for chemical vapor deposition which can solve the aforementioned problems.

It is an object of the present invention to provide a gas diffusion chamber that can be greatly diffused and mixed.

In order to achieve the above object, the present invention provides a gas diffusion chamber for depositing a thin film on a substrate, comprising: a cavity; a substrate region located inside the cavity for carrying the substrate; at least two The air inlet ends are oppositely disposed on opposite sides of the cavity for supplying gas to the substrate area; and at least two pumping ends are oppositely disposed on the other sides of the cavity for receiving from the substrate area The gas is withdrawn, and the direction of the gas extracted by the suction ends is parallel to the bottom surface of the cavity; wherein the direction of the extracted gas is perpendicular to the direction of the supply gas.

The invention is designed with a horizontal two-way intake air inlet, and a narrow suction design with two opposite suction sides. When the gas is introduced into the cavity, it can be greatly diffused and mixed.

Therefore, the flow channel design and arrangement inside the cavity can change the airflow into the main flow field structure of the cavity, so that the airflow carried by the suction end can be more effectively and uniformly mixed for chemical vapor deposition, thereby Film deposition uniformity is improved.

The above and other objects, features, and advantages of the present invention will become more apparent from the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective perspective view of a gas diffusion chamber in accordance with an embodiment of the present invention. Figure 2 is a top plan view of a gas diffusion chamber in accordance with an embodiment of the present invention. Figure 3 is a cross-sectional view taken along line AA' of Figure 2; Figure 4 is a cross-sectional view taken along line BB' of Figure 2; Referring to FIG. 1 to FIG. 4, the gas diffusion chamber 100 is configured to deposit a film on a substrate 210. The gas diffusion chamber 100 includes a cavity 110, a substrate region 120, two pumping ends, and two Intake end and a supplement end 130. For convenience of explanation, The two pumping ends are a first pumping end 141 and a second pumping end 142, respectively. The two intake ends are a first intake end 151 and a second intake end 152, respectively.

The substrate region 120 is located inside the cavity 110 for carrying the substrate 210. In the embodiment of the present invention, the substrate region 120 has a substrate heating device 121, and the substrate heating device 121 has a substrate heating recess region 122. The substrate heating recessed area 122 is used to place the substrate 210 such that the substrate 210 does not protrude inside the cavity 110. The substrate heating device 121 can perform a heating operation on the substrate 210.

Two inlet ends 151, 152 are oppositely disposed on opposite sides of the cavity 110 for supplying gas to the region of the substrate region 210. In the embodiment of the present invention, the first air inlet end 151 is disposed on the left side surface 113 of the interior of the cavity 110, and the second air inlet end 152 is disposed on the right side surface 114 of the interior of the cavity 110, and can be used simultaneously to the substrate area. The 120 area provides gas. Please refer to FIG. 5 , which is a schematic diagram of a diffusion plate according to the present invention. In order to make the flow rate and flow rate of the gas more stable, a diffusion plate 160 may be disposed between the inlet ends 151 , 152 and the substrate region 120 , and the diffusion plate 160 . There are a plurality of holes 161 there, which may be arranged in a matrix or in a staggered manner. The arrangement of the diffuser plate 160 does not limit the scope of the patent implementation of the present invention.

Two pumping ends 141, 142 are oppositely disposed on opposite sides of the cavity 110 for extracting gas from the region of the substrate region 120. In the embodiment of the present invention, the first pumping end 141 is disposed on the front side 115 of the cavity 110, the second pumping end 142 is disposed inside the cavity 110, and the first pumping end 141. And the second pumping end 142 is located at the two ends of the center line of the substrate region 120, so that the exhausting gas directions of the pumping ends 141, 142 The gas supply directions are perpendicular to the gas supply ends 151, 152, and the gas extraction ends 141, 142 are drawn in a direction parallel to the bottom surface 112 of the cavity 110.

The first pumping end 141 and the second pumping end 142 are controlled by a total pumping end 180 to control the flow rate and flow rate of the first pumping end 141 and the second pumping end 142 during pumping.

Referring to FIG. 6 at the same time, the connection between the first pumping end 141 and the front side 115 of the cavity 110 is designed at an arc angle, so that the gas in the cavity 110 can flow into the first pumping end 141 to be smoother. The flow rate and flow rate of the chamber 110 gas 200 (indicated by the arrows indicating the flow of gas and gas) are more stable. Similarly, the junction of the second pumping end 142 and the rear side of the cavity is also designed at an arc angle. The first pumping end 141 and the second pumping end 142 are used for extracting gas from the direction of the substrate region 120, and the cross-sectional areas of the pumping ends 141 and 142 are 0.08 of the cross-sectional area of the inlet ends 151 and 152. Doubled to 0.14 times.

The gas supply end 130 is elongated and disposed on the top surface 111 of the cavity 110 and located directly above the substrate region 120 and along the center line of the substrate region 120. Referring to FIG. 7 at the same time, the air supply end 130 has a plurality of holes 131, which may be arranged in a matrix or in a staggered manner, and each of the holes has a hole depth of 1 to 5 (mm) and a hole diameter of 0.5. Between ~1 (mm), the flow rate and flow rate of the gas sent from the gas supply end 130 can be made more stable.

The first intake end 151, the second intake end 152, and the supplemental end 130 can be individually controlled by a system MFC (Mass Flow Rate Controller) to control the flow rate or flow rate of the intake air.

For example, taking a substrate of 2.5 generations as an example, the substrate size is 300×300 (mm), so the length and width of the gas diffusion chamber 100 are 500×500×60 (mm). The cavity 110 of the gas diffusion chamber 100 has a length a width b of 500 to 320 (mm) and a height c of 25 (mm). The area of the substrate region 120 needs to be larger than the substrate size, so the length d width e of the substrate region 120 may be 320×320 (mm). The lengths of the inlet ends 151, 152 are the same as the length a of the cavity 110 at 320 to 500 (mm), and the widths of the inlet ends 151, 152 are 25 (mm) as the height c of the cavity 110. The width f of the area of the pumping ends 141, 142 is 32~50 (mm), that is, extending from the center to the sides by about 16~25 (mm), the heights of the pumping ends 141, 142 and the cavity The height f of 110 is also 25 (mm). The length of the air supply ends 151, 152 is the same as the length a of the cavity 110 between 320 and 500 (mm), and the width g of the air supply end 130 is 60 (mm), which means that the center extends to the sides. 30 (mm).

It is assumed that when the gas diffusion chamber is used for plasma-enhanced CVD (PECVD), an upper electrode plate and a lower electrode plate need to be added inside the cavity, and are respectively disposed at the top of the cavity. The surface and the bottom surface, and the height of the cavity is defined as the distance from the upper electrode plate to the lower electrode plate. Therefore, the gas diffusion chamber of the present invention can be correspondingly changed according to different chemical vapor deposition processes, and the chemical vapor deposition process It can be: Atmospheric Pressure CVD (APCVD), Low Pressure CVD (LPCVD), Plasma Enhanced Chemical Vapor Deposition, Metalorganic Chemical Vapor Deposition (Metalorganic Chemical Vapor Deposition). , MOCVD), and other chemical vapor deposition processes.

The invention is designed with an air intake of two horizontally opposite intake ends, and is matched with The narrow suction design of the two opposite suction sides can be greatly diffused and mixed when the gas is introduced into the cavity. Furthermore, the present invention may form a local stagnation zone in the middle of the design of the two opposite intake airs, so that the local intake air at the air supply end of the upper edge of the cavity is further introduced to avoid the uniform problem derived from the airflow stagnation, but the qi is supplemented. The role played by the end is only an auxiliary function, so a long strip will be formed, which will greatly reduce the hole requirement of the top surface of the cavity, thereby reducing the processing and maintenance costs.

Therefore, the flow channel design and arrangement inside the cavity can change the airflow into the main flow field structure of the cavity, so that the airflow carried by the suction end can be more effectively and uniformly mixed for chemical vapor deposition, thereby Film deposition uniformity is improved.

In the above, it is merely described that the present invention is an embodiment or an embodiment of the technical means for solving the problem, and is not intended to limit the scope of implementation of the present invention. That is, the equivalent changes and modifications made in accordance with the scope of the patent application of the present invention or the scope of the invention are covered by the scope of the invention.

100‧‧‧ gas diffusion chamber

110‧‧‧ cavity

111‧‧‧ top surface

112‧‧‧ bottom

113‧‧‧left side

114‧‧‧ right side

115‧‧‧ front side

116‧‧‧Back side

120‧‧‧Substrate area

121‧‧‧Substrate heating device

122‧‧‧Substrate heating recess

130‧‧‧ qi end

131‧‧‧ holes

141‧‧‧first pumping end

142‧‧‧second pumping end

151‧‧‧First intake end

152‧‧‧second intake end

160‧‧‧Diffuser

161‧‧‧ hole

180‧‧‧Total pumping end

200‧‧‧ gas

210‧‧‧Substrate

A‧‧‧ cavity length distance

B‧‧‧ cavity width distance

C‧‧‧cavity height distance

d‧‧‧Drop area length distance

e‧‧‧Drop area width distance

f‧‧‧Exhaust end width distance

g‧‧‧Vending end width distance

1 is a perspective view of a gas diffusion chamber according to an embodiment of the present invention; FIG. 2 is a top view of a gas diffusion chamber according to an embodiment of the present invention; FIG. 3 is a cross-sectional view taken along line AA' of FIG. 2; 'The line drawing; Fig. 5 is a partial enlarged view of the diffusing plate; Fig. 6 is a partial enlarged view of the first pumping end; and Fig. 7 is a partial enlarged view of the air outlet of the air supply end.

100‧‧‧ gas diffusion chamber

120‧‧‧Substrate area

130‧‧‧ qi end

141‧‧‧first pumping end

142‧‧‧second pumping end

151‧‧‧First intake end

152‧‧‧second intake end

180‧‧‧Total pumping end

Claims (10)

A gas diffusion chamber for depositing a film on a substrate comprises: a cavity; a substrate region located inside the cavity for carrying the substrate; at least two inlet ends disposed opposite to each other Two sides of the cavity for supplying gas to the substrate region; and at least two pumping ends disposed opposite to each other on the other side of the cavity for extracting gas from the substrate region, and the pumping The direction in which the gas is withdrawn is parallel to a bottom surface of the interior of the cavity; wherein the direction of the extracted gas is perpendicular to the direction of the gas supply. The gas diffusion chamber of claim 1, wherein the cross-sectional areas of the suction ends are between 0.08 and 0.14 times the cross-sectional area of the intake ends. The gas diffusion chamber of claim 1, wherein the suction end is disposed on a side of the cavity, and the connection between the suction end and the side of the cavity is designed at an arc angle. The gas diffusion chamber of claim 1, wherein the suction ends are located at both ends of the center line of the substrate region and are disposed on a side of the cavity. The gas diffusion chamber of claim 1, wherein a diffusion plate is disposed between the inlet ends and the substrate region, and the diffusion plate has a plurality of holes. For example, the gas diffusion chamber described in claim 1 of the patent scope includes a supplement The gas end is located directly above the substrate area. The gas diffusion chamber of claim 6, wherein the gas supply end is elongated, along a center line of the substrate region, and disposed on a top surface of the cavity. The gas diffusion chamber of claim 6, wherein the gas supply end has a plurality of holes. The gas diffusion chamber of claim 8, wherein each of the holes has a depth of between 1 and 5 (mm). The gas diffusion chamber of claim 8, wherein each of the holes has a pore diameter of between 0.5 and 1 (mm).