KR100697267B1 - A chemical vapor deposition apparatus - Google Patents

Abstract

The present invention relates to a chemical vapor deposition apparatus for forming a thin film on the surface of a semiconductor wafer, the chemical vapor deposition apparatus of the present invention is provided in the process chamber and a table having at least two or more stations on which the semiconductor wafer is placed; And a shower head positioned above each station and for injecting process gas into the semiconductor wafer placed in the station. The table here has a ring shaped vacuum port at the edge of each station and the shower head has a ring shaped air floor port at the edge.

Description

Chemical vapor deposition apparatus {A CHEMICAL VAPOR DEPOSITION APPARATUS}

1 is a schematic view showing a process chamber portion of a chemical vapor deposition apparatus for a semiconductor process according to the present invention;

FIG. 2 shows a table with five stations shown in FIG. 1; FIG.

3 is a plan view of the station and the shower head;

4 shows an air curtain formed between a shower head and a station.

Explanation of symbols on the main parts of the drawings

110: process chamber 120: table

130: station 132: vacuum port

140: shower head 142: injection hole

144: air floor port 190: air curtain

200 wafer

The present invention relates to a chemical vapor deposition apparatus for forming a thin film on a semiconductor wafer.

Among the equipment used in the manufacturing process of semiconductor devices, a chemical vapor deposition (CVD) apparatus is used to deposit a thin film on the surface of a semiconductor wafer.

Conventional CVD apparatus has a susceptor (also referred to as a "station") in which a semiconductor wafer is vacuum mounted, a heating unit that applies a high temperature of 400 ° C or more to the susceptor, and evenly sprays the reaction gas onto the semiconductor wafer. It consists of a shower head.

On the other hand, in such a CVD apparatus, process conditions for depositing a predetermined thin film on a semiconductor wafer include maintaining a constant temperature and pressure in a process chamber and a flow amount of a reaction gas through the shower head. Therefore, by appropriately adjusting these process conditions it is possible to improve the uniformity of the film deposited on the semiconductor wafer.

However, CVD facilities having a multi-station structure among the existing CVD facilities generally allow temperature control for each station, but pressure control uses a single vacuum port, so separate control at each station is not possible. In general, the depot rate is improved during the process at high pressure, but GAP FILL and particle management is difficult, and if the pressure is low, the GAP FILL and particle management ability is improved, but the depot rate has the opposite characteristics.

 The present invention is to solve such a conventional problem, the object is to provide a new type of chemical vapor deposition apparatus capable of pressure control for each station.

According to a feature of the present invention for achieving the above object, a chemical vapor deposition apparatus for forming a thin film on the surface of a semiconductor wafer comprising: at least two stations provided inside a process chamber and on which a semiconductor wafer is placed; Table; A shower head positioned above each station and for injecting a process gas into a semiconductor wafer placed in the station; The table has a ring-shaped vacuum port at the edge of each station, and the shower head has a ring-shaped air floor port at the edge.

In this invention, the ring size of the air floor port is preferably larger than the ring size of the vacuum port.

In the present invention as described above may further include a separate throttle valve for the station pressure control of each of the table.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to FIGS. 1 to 4. In addition, in the drawings, the same reference numerals are denoted together for components that perform the same function.

1 is a schematic diagram showing a process chamber portion of a chemical vapor deposition apparatus for a semiconductor process according to the present invention, and FIG. 2 shows a table with five stations shown in FIG. 1.

The basic configuration of the CVD apparatus shown in FIG. 1 includes a process chamber 110 for causing a chemical reaction, a loading / unloading unit of a wafer, and a controller for controlling the entire process. A plurality of wafers are disposed in the process chamber, including a heating heater, a table 120, a shower head 140, and the like. In addition, a gas control system and a vacuum exhaust system are also installed.

As shown in FIGS. 1 to 3, the table 120 is installed inside the process chamber 110. Five stations 130 on which the wafers 200 are placed are arranged radially on the table 120. The main vacuum hole 122 for controlling the internal pressure of the process chamber 110 is formed at the center of the table 120. On the other hand, the shower head 140 is installed by the support on the upper side of the process chamber 110 to receive the reaction gas and to spray the surface of the wafer 200 placed on the station 130. The shower head 140 is disposed to correspond to the station 130, respectively. The shower head 140 has a plurality of injection holes 142 formed at a lower surface thereof, and a reaction gas supplied from an external gas supply system (not shown) via a gas supply pipe passes through the injection holes 142. It is supplied constant in the direction through.

On the other hand, the station 130 and the shower head 140 is provided with a vacuum port 132 and the air floor port 144 to control the pressure on each station separately. The vacuum port 132 is formed in a ring shape at the edge of the station 130 corresponding to the outer surface of the portion where the wafer is placed. In addition, the air floor port 144 is formed in a ring shape at the edge of the shower head 140 corresponding to the outside of the portion where the plurality of injection holes 142 are formed. Air injected from the air floor port 144 is sucked into the vacuum port 132.

For example, as shown in FIG. 3, the diameter A of the vacuum port 132 formed in the station 130 is smaller than the diameter B of the air floor port 144 formed in the shower head 140. desirable. On the other hand, separate throttle valves for controlling each station pressure may be installed on a line for supplying air to the air floor port 144 of the shower head 140 or a line through which air sucked into the vacuum port is exhausted. .

4 illustrates a flow of air injected from the air floor port 144 of the shower head 140. As shown in FIG. 4, air injected from the air floor port 144 of the shower head 140 flows into the vacuum port 132 of the station 130 to form an air curtain 190. Due to the air curtain 190 formed as described above, the inner space of the air curtain in which the wafer 200 is positioned (the portion owed to FIG. 4) is not directly affected by the external chamber pressure, and thus the multi-station It is possible to manage by setting the pressure for each station in the process chamber having a separate.

The shower head and the corresponding station according to the embodiment of the present invention are cold-walled, warm-walled, which deposits a thin film on a semiconductor wafer using a chemical reaction, and an atmospheric pressure (AP) CVD which causes a reaction under atmospheric pressure. It can be usefully applied to other types of CVD apparatuses in which a showerhead is used, such as low pressure (LP) CVD and plasma CVD apparatuses.

According to the present invention, since the pressure can be set and managed separately for each station, the advantage of improving the gap fill and particle management at low pressure and the depot rate at high pressure can be improved. There is this.

Claims (3)

In a chemical vapor deposition apparatus for forming a thin film on the surface of a semiconductor wafer: A table provided inside the process chamber and having at least two stations on which semiconductor wafers are placed; A shower head positioned above each station and for injecting a process gas into a semiconductor wafer placed in the station; The table is provided with a ring-shaped vacuum port at the edge of each station, The shower head is installed at the edge of the ring-shaped air floor port, Chemical vapor deposition apparatus characterized in that the pressure control for each station is formed by the curtain formed by the air flowing from the air floor port of the shower head to the vacuum port of the station. The method of claim 1, The ring size of the air floor port is larger than the ring size of the vacuum port chemical vapor deposition apparatus. The method of claim 1, Chemical vapor deposition apparatus further comprises a separate throttle valve for pressure control of each station of the table.

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