JPH06275535A - Semiconductor manufacturing device - Google Patents

Abstract

PURPOSE:To obtain a semiconductor manufacturing device in which the generation of fine dust is prevented and which is suitable for CVD devices or epitaxial growth devices. CONSTITUTION:The title device is constituted of a reaction chamber 1 maintained in a reduced-pressure state, load lock chamber 10 which is connected to the chamber 1 through a first gate valve 11 and can be maintained at an atmospheric pressure or reduced-pressure by switching, and by-pass pipe 19 which communicates the chambers 1 and 10 with each other through a valve 18 and the valve 18 is opened before opening the gate valve 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device, and more particularly to a CVD device and an epitaxial growth device which prevent generation of fine dust.

[0002]

2. Description of the Related Art An apparatus for causing a reactive gas to act on the surface of a semiconductor wafer under reduced pressure is used for manufacturing a semiconductor element. An example thereof will be described below with reference to FIG. In the figure, 1 is a cylindrical reaction chamber with one end closed and the other end is open, 2 is a susceptor housed in the reaction chamber 1, and a semiconductor wafer 3 is placed on the upper surface thereof, and a motor (not shown) is used to move it on a horizontal plane. Rotate. Reference numeral 4 denotes an electrode arranged above the susceptor 2. The reaction chamber 1 has a reaction gas supply port 1
a is opened, and a first exhaust duct 7 communicating with the first main valve 5 and the first exhaust pump 6 is further connected. Reference numeral 8 represents a first pressure gauge for detecting the pressure in the reaction chamber 1. Reference numeral 9 denotes a carrier containing the wafer 3, which is arranged outside the open end of the reaction chamber 1. Reference numeral 10 denotes a cylindrical load lock chamber which is connected to the open end of the reaction chamber 1 via a first gate valve 11 and whose other end facing the carrier 9 is opened and closed by a second gate valve 12. In the load lock chamber 10, a gas supply port 10a for supplying nitrogen gas for returning from a depressurized state to atmospheric pressure is opened, and a second main valve 13 and a second exhaust pump 14 communicating with each other are provided. The exhaust duct 15 is connected. Reference numeral 16 denotes a second pressure gauge that detects the pressure in the load lock chamber 10. In the load lock chamber 10, the reaction chamber 1 and the load lock chamber 10,
A robot 17 that transfers the wafer 3 is arranged between the carrier 9 and the load lock chamber 10.

The operation of this device will be described below.

The first gate valve 11 is closed and the first exhaust pump 6 is operated to reduce the pressure in the reaction chamber 1.
While keeping this state, the second gate valve 12 is opened, a predetermined wafer 3 is taken into the load lock chamber 10 from the carrier 9, the second gate valve 12 is closed, and the second exhaust pump 14 is operated to load the wafer. Decompress the lock chamber.
Then, when the values of the pressure gauges 8 and 16 become substantially the same, the first gate valve 11 is opened, and the robot 17 transfers the wafer 3 to the susceptor 2. When the transfer is completed, the first gate valve 11 is closed, a high frequency voltage is applied to the electrode 4 while supplying the reactive gas, and a reaction product film is formed on the wafer 3. When the film formation is completed, it is confirmed that the values of the pressure gauges 8 and 16 are in the same state, and then the first gate valve 11 is opened.
Is taken into the load lock chamber 10, and the first gate valve 11 is closed. Then, nitrogen is supplied from the gas supply port 10a to return the load lock chamber 10 to the atmospheric pressure, the second gate valve 12 is opened, and the wafer 17 is returned to the carrier 9 by the robot 17. Thereafter, the above operation is repeated, and the wafer 3
A reaction product film is formed on top.

[0005]

By the way, in the above apparatus, the reaction product generated in the reaction chamber 1 adheres not only to the surface of the wafer 3 but also to the surface of the susceptor 2 and the inner wall of the reaction chamber 1 and is localized. It is peeled off and can float.

On the other hand, opening and closing of the first gate valve 11
It is performed when the values of the pressure gauges 8 and 16 become the same, but the first gate is operated in a state where a pressure difference remains between the reaction chamber 1 and the load lock chamber 10 due to an error or failure of the pressure gauges 8 and 16. When the valve 11 is opened, an air flow is generated between the two chambers, and floating pieces of the product may adhere to the wafer 3 and cause a semiconductor device failure. Therefore, it suffices to detect the error or failure of the pressure gauge at an early stage and replace it immediately if it is defective so that a pressure difference will not occur, but the pressure gauge cannot be calibrated while the equipment is operating. However, there was a problem in that a large amount of wafers were processed until the defects were found to be defective for the first time during the periodic inspection.

[0007]

DISCLOSURE OF THE INVENTION The present invention has been proposed for the purpose of solving the above-mentioned problems, and has a tubular reaction chamber in which the inside is kept in a depressurized state and one end side is closed and the other end side is open.
A robot that transfers wafers between the carrier containing the wafer and the opening end of the reaction chamber is arranged on both sides via the first and second gate valves. In a semiconductor device having a cylindrical load lock chamber that can be switched to a reduced pressure state, and opening and closing a gate valve to deliver wafers when the pressure in the reaction chamber and the pressure in the load lock chamber are approximately the same, And a load lock chamber are connected by a bypass pipe through a valve, and the valve of the bypass pipe is opened prior to opening the gate valve on the reaction chamber side.

Further, the present invention is characterized in that a susceptor for supporting a wafer is housed in the reaction chamber to supply a reaction gas.

Further, a porous filter is arranged in the path of the bypass pipe.

[0010]

With the above structure, the pressure difference can be eliminated by connecting the chambers with the bypass pipe before opening the gate valve between the reaction chamber and the load lock chamber. Since it does not occur, it is possible to prevent foreign matter from flying up and adhering to the wafer.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the invention will be described below with reference to FIG.

In the figure, the same reference numerals as those in FIG. The only difference in the figures is that the reaction chamber 1 and the load lock chamber 10 are communicated with each other by a bypass pipe 19 via a valve 18.

The operation of the device of the present invention will be described below.

The basic operation is the same as in FIG. In the device of the present invention, before the first gate valve 11 is opened with the first gate valve 11 closed and the pressure inside the reaction chamber 1 and the load lock chamber 10 being substantially equal. The valve 18 is opened, and the pressures inside the reaction chamber 1 and the load lock chamber 10 are equalized by the bypass pipe 19. After that, the first gate valve 11 is opened and the wafer 3 is transferred. According to this embodiment, the pressure between the reaction chamber 1 and the load lock chamber 10 can be eliminated before opening the first gate valve even if the pressure gauges 8 and 16 have an error or a defect. There is no air flow between them, so there is no floating of the product and it is possible to prevent the floating pieces from adhering to the wafer. Further, even if some errors occur in the pressure gauges 8 and 16, the work can be continued without stopping the equipment.

The present invention is not limited to the above embodiment, and for example, the susceptor 2 and the electrode 4 are provided in the reaction chamber 1.
It is also possible to omit the above and add a heating device to form an epitaxial growth device. Furthermore, the reaction chamber may be a sputtering chamber. Further, as the bypass pipe 19, a thin filter may be used, and a porous filter may be arranged in the path of the pipe.

[0016]

As described above, according to the present invention, no airflow is generated when the gate valve between the reaction chamber and the load lock chamber is opened, and floating products adhere to the wafer to prevent the semiconductor device from being damaged. It can also be prevented from becoming defective.

Further, even if some error of the pressure gauge occurs, it does not affect the operation of the equipment and the operation rate of the equipment is improved.

[Brief description of drawings]

FIG. 1 is a side sectional view of a semiconductor device showing an embodiment of the present invention.

FIG. 2 is a side sectional view showing an example of a conventional semiconductor device.

[Explanation of symbols]

 1 Reaction Chamber 2 Susceptor 3 Wafer 9 Carrier 10 Load Lock Chamber 11 First Gate Valve 12 Second Gate Valve 17 Robot 18 Valve 19 Bypass Pipe

Claims (3)

[Claims] 1. A first and a second reaction chambers are provided between a cylindrical reaction chamber whose inside is kept in a depressurized state and which is closed at one end and opened at the other end, and between a carrier containing a wafer and an open end of the reaction chamber. Each of which is provided with a gate valve, accommodates a robot for transferring wafers between them, and is provided with a cylindrical load lock chamber capable of switching between an atmospheric pressure and a reduced pressure state,
In a semiconductor device in which a gate valve is opened and a wafer is transferred when the pressure in the reaction chamber and the pressure in the load lock chamber become substantially the same, the reaction chamber and the load lock chamber are connected by a bypass pipe via the valve. At the same time, the semiconductor device is characterized in that the valve of the bypass pipe is opened prior to opening the gate valve on the reaction chamber side. 2. A semiconductor device according to claim 1, wherein a susceptor for supporting the wafer is housed in the reaction chamber to supply a reactive gas. 3. The semiconductor device according to claim 1, wherein a porous filter is arranged in the path of the bypass pipe.