KR20010107138A - Chemical vapor deposition apparatus - Google Patents

Abstract

The present invention relates to chemical vapor deposition equipment installed to enable automatic pressure control of a process chamber and a load lock chamber. Chemical vapor deposition equipment is connected to the process chamber, a load lock chamber connected to the process chamber by a gate valve, a vacuum pump connected to the process chamber and the load lock chamber to regulate the vacuum state, respectively connecting the process chamber and the load lock chamber with the vacuum pump First and second purge lines connected to the first and second vacuum lines, the process chamber and the load lock chamber, respectively, to evacuate the purge gas, a pressure regulating gas line and a gas line connecting the process chamber and the load lock chamber. It includes a pressure regulating valve installed in. If it is impossible to equally regulate the pressure in the process chamber and the load lock chamber by the first and second purge lines, open the pressure regulating valve. Then, the process chamber and the load lock chamber are connected through the pressure adjusting gas line so that the pressure in each chamber is equally adjusted.

Description

Chemical Vapor Deposition Equipment {CHEMICAL VAPOR DEPOSITION APPARATUS}

The present invention relates to semiconductor manufacturing equipment, and more particularly to chemical vapor deposition equipment having a load lock chamber.

A silicon nitride film used as an etch stop film or the like in a semiconductor device is formed by a chemical vapor deposition method. The chemical vapor deposition process for forming the silicon nitride film is carried out using NH ₃ and SiH ₂ Cl ₂ gas, which generates a considerable amount of by-product powder by the reaction of the gases. These powders are adsorbed on the inner wall of the process chamber to contaminate the process chamber as well as to thickly accumulate on the inner wall of the exhaust line when exhausted to the outside, thereby degrading the function of the exhaust line.

Referring to Figure 1 will be described in detail the problems of the prior art.

1 is a block diagram showing a chemical vapor deposition equipment having a load lock chamber constructed by the prior art.

Referring to FIG. 1, a load lock chamber 110 connected through a process chamber 100 and a gate valve 104 is provided. A vacuum pump 120 is provided to maintain the vacuum of the process chamber 100 and the load lock chamber 110. The process chamber 100 is connected with the vacuum pump 120 through the first vacuum line 130, and the load lock chamber 110 is connected with the vacuum pump 120 through the second vacuum line 134. Vacuum valves 150 and 154 are provided on the first and second vacuum lines 130 and 134, respectively. When purging the process chamber 100 and the load lock chamber 110, a first purge line 140 and a second purge line 144 for evacuating the supplied nitrogen gas are installed. Purge valves 156 and 158 are provided on the first and second purge lines, respectively.

When the thin film forming process is completed and the semiconductor wafer is discharged from the process chamber 100, a purge process of injecting nitrogen gas and evacuating the gas to remove contaminants remaining in the process chamber 100 before the new semiconductor wafers are introduced is performed. Proceed. Nitrogen gas supplied to the process chamber 100 is discharged through the first purge line 140.

Meanwhile, a purge process is performed to remove contaminants present on the surfaces of the semiconductor wafers even in the load lock chamber 110 into which the new semiconductor wafers are introduced. Nitrogen gas supplied to the load lock chamber 110 is discharged through the second purge line 144.

When the purge process is completed, the supply of nitrogen is stopped and the first and second purge lines 140 and 144 are blocked by the purge valves 156 and 158. In addition, the gate valve 104 is opened to move the semiconductor wafer from the load lock chamber 110 to the process chamber 100. In this case, when a pressure difference occurs between the process chamber 100 and the load lock chamber 110, the flow of gas is generated, and thus the pressure of each chamber must be equally adjusted. Pressure control of the process chamber 100 and the load lock chamber 110 is performed by manually adjusting the purge valve 156 installed on the first purge line 140.

However, when the powders generated in the process of forming the silicon nitride film are accumulated on the inner wall of the first purge line 140, the internal space of the first purge line 140 is narrowed, and exhaustion is not performed smoothly. Then, since the pressure control through the purge valve 156 is impossible, the pressure of the process chamber 100 becomes higher than the pressure of the load lock chamber 110 when the purge process is completed.

In this case, when the gate valve 104 is opened, since the pressure in the process chamber 100 is high, a gas flow is formed by the pressure difference from the process chamber 100 toward the load lock chamber 110. Due to the instantaneous gas flow, the powder adsorbed on the inner wall of the process chamber 100 is separated from the inner wall of the process chamber 100 and moved to the load lock chamber 110. Then, a problem arises in that the semiconductor wafers waiting in the load lock chamber 110 are contaminated by powder.

The present invention has been proposed to solve the above-mentioned problems, and to provide a chemical vapor deposition apparatus capable of equally adjusting the pressure of the process chamber and the load lock chamber before loading the semiconductor wafer from the load lock chamber to the process chamber. The purpose is.

1 is a block diagram showing a chemical vapor deposition equipment according to the prior art.

2 is a block diagram showing a chemical vapor deposition equipment according to an embodiment of the present invention.

* Explanation of symbols for the main parts of the drawings

100, 200: process chamber 110, 210: load lock chamber

104, 204: gate valve 120, 220: vacuum pump

130, 230: first vacuum line 134, 234: second vacuum line

140, 240: first purge line 144, 244: second purge line

260: gas line for pressure regulation

150, 154, 156, 158, 250, 254, 256, 258, 264: valve

(Configuration)

According to the present invention for achieving the above object, the chemical vapor deposition apparatus, the process chamber in which the thin film deposition process is performed, the load lock chamber connected to the process chamber, the process chamber and the connection portion of the load lock chamber is installed A gate valve which disconnects or connects between the process chamber and the load lock chamber, a vacuum pump connected to the process chamber and the load lock chamber to regulate a vacuum state, and a first vacuum line connecting the vacuum pump and the process chamber A second purge line connecting the vacuum pump and the load lock chamber, a first purge line connected to the process chamber to exhaust the purge gas, and a second purge connected to the load lock chamber to exhaust the purge gas A line, a pressure regulating gas line connecting the process chamber and the load lock chamber, and a pressure regulating gas line. It characterized in that it comprises a pressure regulating valve installed.

Preferably, the pressure adjusting gas line is branched from the first vacuum line and connected to the second vacuum line.

The pressure regulating valve is preferably an air valve that can be opened and closed automatically.

(Example)

Hereinafter, an embodiment of the present invention will be described in detail with reference to FIG. 2.

2 is a block diagram showing a chemical vapor deposition equipment according to an embodiment of the present invention.

Referring to FIG. 2, a process chamber 200 in which a chemical vapor deposition process of forming a thin film on a semiconductor wafer is performed is provided. The load lock chamber 210 is provided to be connected to the process chamber 200 to become a space where the semiconductor wafer enters and exits. Since the loading and discharging of the semiconductor wafer is performed through the load lock chamber 210, the process chamber 200 is prevented from being directly exposed to the external environment. A gate valve 204 is installed between the process chamber 200 and the load lock chamber 210 to connect or disconnect the chambers.

A vacuum pump 220 is provided to maintain the process chamber 200 and the load lock chamber 210 in a vacuum state. The process chamber 200 is connected to the vacuum pump 220 by a first vacuum valve 250 installed on the first vacuum line 230. The load lock chamber 210 is connected to the vacuum pump 220 by a second vacuum valve 254 installed on the second vacuum line 234.

Although not shown in the drawing, each of the process chamber 200 and the load lock chamber 210 is connected to a nitrogen gas supply source for supplying nitrogen gas, which is a purge gas. The purge process is carried out to bring the interior of the vacuum chamber to atmospheric pressure or to remove gases or contaminants remaining inside the chamber. As the purge process proceeds, a first purge line 240 and a second purge line 244 are provided for evacuating the supplied nitrogen gas gases. The first purge valve 256 and the second purge valve 258 are installed on the first and second purge lines 240 and 244, respectively.

In order to connect the process chamber 200 and the load lock chamber 210 in a state in which the gate valve 204 is closed, a pressure regulating gas line 260 is installed. The pressure regulating gas line 260 is installed as a normal gas conveying tube, and is preferably branched from the first vacuum line 230 between the process chamber 200 and the first vacuum valve 250 to load rod chamber ( It is installed to be connected to the second vacuum line 260 between the 210 and the second vacuum valve (254). A pressure regulating valve 264 is installed on the pressure regulating gas line 264. The pressure regulating valve 264 is preferably installed as an air valve that can automatically control the opening and closing.

When the chemical vapor deposition process is completed, first, the first vacuum valve 250 is closed to disconnect the connection between the vacuum pump 220 and the process chamber 200. Subsequently, nitrogen gas is supplied into the process chamber 200 to bring the process chamber 200 to an atmospheric pressure. When the process chamber 200 reaches the normal pressure, the gate valve 204 is opened and the semiconductor wafer on which the thin film is formed is discharged to the outside through the load lock chamber 210.

A purge process using nitrogen gas is performed to remove contaminants in the process chamber 200 until immediately before a new semiconductor wafer is loaded into the process chamber 200. The supplied nitrogen gas and contaminants are exhausted through the first purge line 240.

Meanwhile, when new semiconductor wafers are introduced into the load lock chamber 210, a purge process is performed in the load lock chamber 210 to remove contaminants existing on the surface of the semiconductor wafer. Nitrogen gases supplied to the load lock chamber 210 are exhausted through the second purge line 244.

While the semiconductor wafer is waiting in the load lock chamber 210, the process chamber 200 and the load lock chamber 210 are exhausted by the first and second purge lines 240 and 244, respectively. However, if the first purge line 240 is contaminated by the powders generated during the process and the exhaust of the process chamber 200 is not smoothly performed, the pressure of the process chamber 200 may be the pressure of the load lock chamber 210. Higher. In this case, the pressure regulating valve 264 is opened to connect the process chamber 200 and the load lock chamber 210 through the pressure regulating gas line 260. As a result, the pressure difference between the process chamber 200 and the load lock chamber 210 is eliminated, resulting in the same pressure state.

When the process chamber 200 and the load lock chamber 210 reach the same pressure, the pressure control valve 264, the first purge valve 256, and the second purge valve 258 are all closed to close the process chamber 200. ) And the load lock chamber 210 from the external environment. Thereafter, the gate valve 204 is opened to supply the semiconductor wafer in the load lock chamber 210 to the process chamber 200.

According to the present invention, a pressure adjusting gas line 260 for adjusting the pressure of the process chamber 200 and the load lock chamber 210 in the step of loading the semiconductor wafer is installed. Therefore, even when the first purge line 240 is contaminated and the pressure of the process chamber 200 becomes higher than the pressure of the load lock chamber 210, the process chamber 200 and the load lock chamber through the pressure adjusting gas line 260. The pressure of 210 can be equally adjusted.

According to the present invention, a pressure adjusting gas line is installed so that the pressures of the process chamber and the load lock chamber are equally adjusted. Thus, powders adsorbed on the inner wall of the process chamber are separated due to the pressure difference between the two chambers, thereby separating the semiconductor wafer in the load lock chamber. It is effective to prevent contamination. In addition, since the generation of powder due to the pressure difference is prevented, the maintenance cycle of the purge line is extended, the pressure control is automatically adjusted by opening and closing of the valve, there is an effect that the operation becomes easy.

Claims (3)

A process chamber in which a thin film deposition process is performed, A load lock chamber connected to the process chamber, A gate valve installed at a connection portion of the process chamber and the load lock chamber to block or connect the process chamber and the load lock chamber; A vacuum pump connected to the process chamber and the load lock chamber to regulate a vacuum state, A first vacuum line connecting the vacuum pump and the process chamber, A second vacuum line connecting the vacuum pump and the load lock chamber, A first purge line connected to the process chamber to exhaust a purge gas; A second purge line connected to the load lock chamber to exhaust a purge gas; A gas line for pressure regulation connecting the process chamber and the load lock chamber; And a pressure regulating valve installed on the pressure regulating gas line. The method of claim 1, And the gas line for pressure control is branched from the first vacuum line and connected to the second vacuum line. The method of claim 1, The pressure regulating valve is a chemical vapor deposition equipment, characterized in that the automatic opening and closing of the air valve.