KR0137968Y1 - Apparatus for regulating inner pressure of reacting chamber of low pressure cvd - Google Patents

Abstract

The present invention relates to an internal pressure control device of a reactor for atmospheric chemical vapor deposition equipment. In opening and closing a gate door to load and unload a wafer, the internal pressure of the reactor is equal to the external pressure and then the gate door is opened. It is configured to prevent the inflow of particles generated due to the pressure difference between the inside and outside of the reactor by opening, this invention device is such that the exhaust flow rate automatic control valve 10 to the exhaust pipe (6) of the reactor (2) In addition, a mass flow controller 11 for adjusting the amount of purge nitrogen gas is installed at the nitrogen inlet 1 of the reactor 2, and the exhaust flow rate automatic control valve 10 and the mass flow controller 11 are installed. A controller 12 for driving is installed to be connected to the gate door 7 of the reactor 2 so that the pressure in the reactor 2 is gradually closed by gradually closing the exhaust flow rate automatic control valve 10 before the gate door 7 is opened.It is characterized in that it is configured to remain the same as the outside.

Description

Reactor internal pressure regulator of atmospheric chemical vapor deposition equipment

1 is a schematic structural diagram of a conventional atmospheric chemical vapor deposition equipment.

2 is an air flow acceleration principle in the gate of the atmospheric chemical vapor deposition equipment.

3 is a schematic structural diagram of an atmospheric chemical vapor deposition apparatus to which the present invention device is applied.

Figure 4 is a flow diagram of the operation of the reactor internal pressure regulator of the present invention.

* Explanation of symbols for main parts of the drawings

1: nitrogen inlet 2: reactor

6: exhaust pipe 7: gate door

10: automatic exhaust flow regulating valve 11: mass flow controller

12: controller

The present invention relates to an internal pressure control device of a reactor of atmospheric pressure chemical vapor deposition (CVD) equipment, and in particular, by maintaining the same internal and external pressure in the reactor when opening and closing the gate door. The present invention relates to a reactor internal pressure roughening apparatus of an atmospheric pressure chemical vapor deposition equipment which reduces generation of particles generated by pressure difference, improves the quality of a deposited film due to particle reduction, and is suitable for improving yield.

In general, chemical vapor deposition equipment is a device used in a chemical vapor deposition process that decomposes a gaseous compound and forms a thin film or epi layer on a semiconductor substrate by chemical reaction. This is mainly done by injecting gas from the outside into the reaction chamber without using the material on the silicon wafer.

Here, chemical vapor deposition equipment is classified into atmospheric pressure (atmospheric) chemical vapor deposition (APCVD) equipment and low pressure or reduced pressure chemical vapor deposition (LPCVD) equipment according to the vacuum degree of the reaction chamber during the process.

1 is a schematic structural diagram of a conventional atmospheric chemical vapor deposition equipment, as shown in the drawing, in general, the atmospheric chemical vapor deposition equipment is a wafer support (3) in the interior of the reactor (2) having a nitrogen inlet (1) Is provided, and a gate 5 for loading and unloading the wafer 4 into the reactor 2 is formed at one side of the reactor 2, and the other of the reactor 2 is formed. An exhaust pipe 6 is connected to the side to maintain the inside of the reactor 2 in a process vacuum state.

In addition, the gate door 7 is installed at the inlet of the gate 5 so as to be rotatable and open, and is configured to load and unload the wafer 4.

In the figure, reference numeral 8 shows a wafer feed hole for loading and unloading the wafer 4 into the reactor 2.

Referring to the operation of the general atmospheric chemical vapor deposition equipment configured as described above, the gate door 7 is opened, and the wafer support 3 of the reactor 2 is connected to the wafer 4 through the gate 5 to the wafer transfer port 8. Load in. In such a wafer loading state, the reaction furnace 2 is placed in a process vacuum state, and then a reaction gas is injected to proceed the process. After completion of the process, nitrogen gas is injected through the nitrogen inlet 1 into the reaction furnace 2. After purging, the gate door 7 is opened again to unload the completed wafer.

However, the general atmospheric pressure chemical vapor deposition equipment as described above is different from the pressure inside the reactor 2 and the pressure outside when opening and closing the gate door 7 to load and unload the wafer 4. Due to this, powder (POWDER), which is an unreacted by-product attached to the gate 5, is introduced into the reactor 2, causing product defects and lowering yield.

That is, since the inside of the reactor _{2 has} a pressure of -20 mmH ₂ O due to the exhaust of the reactor, when the gate door 7 is opened to load and unload the wafer 4, the air pressure is increased at a high pressure. The air moves at a high speed through the small inlet of the gate 5 by the principle of air flowing to this low place, and according to the principle as shown in FIG. As the air flows to the wide part (C) through the air, the air velocity becomes very fast in the narrow part (B) (gate part), and the particles attached to the gate part 5 by the fast air flow force ( particle: Powder as unreacted byproduct is introduced into the reactor (2).

As the particles introduced in this way fall on the wafer support 3 and the wafer of the next process is inclined to the wafer support 3, a defect in which the uniformity of the deposited film becomes poor is caused, and the particles are deposited on the wafer 4. There was a disadvantage of falling yield due to falling caused a fatal quantitative amount of the product.

In view of this, the object of the present invention is to maintain the same pressure inside and outside of the reactor when opening and closing the gate valve, so that the particle inside the reactor may be caused by different pressures. It is to provide an internal pressure regulator of the reactor for atmospheric chemical vapor deposition equipment which prevents inflow and prevents product defects.

In order to achieve the object of the present invention as described above, the mass flow controller for controlling the exhaust flow rate automatic control valve is installed in the exhaust pipe of the reactor, and the controller for driving the exhaust flow rate automatic control valve and the mass flow controller is the gate of the reactor. It is installed to be connected to the door, and the pressure control device inside the reactor of atmospheric pressure chemical vapor deposition equipment is configured to adjust the pressure in the reactor to the same as the outside by slowly closing the exhaust flow automatic control valve before the gate door is opened. do.

According to the device of the present invention as described above, when the gate door is opened and closed, the exhaust volume is controlled in proportion to the opening and closing of the door, so that the internal pressure of the reactor is controlled to be the same as that of the outside, so that rapid air flow between the inside and the outside of the reactor is removed Powder, which is a process byproduct attached to the gate part, does not flow into the reactor. Therefore, as in the related art, it is possible to prevent the deposition film non-uniformity and product defects caused by the powder flowing into the reactor, and to improve yield.

Hereinafter, the internal pressure regulator of the reactor for atmospheric chemical vapor deposition equipment according to the present invention as described above will be described based on the accompanying drawings.

3 is a schematic structural diagram of an atmospheric pressure chemical vapor deposition apparatus to which the internal pressure regulator of the present invention is applied, and FIG. 4 is an operation flow diagram of the internal pressure regulator of the reactor according to the present invention. The internal pressure regulator of the reactor for atmospheric vapor chemical vapor deposition equipment is equipped with an exhaust flow rate automatic control valve 10 in the exhaust pipe 6 of the reactor 2 and at the nitrogen inlet 1 of the reactor 2. A mass flow controller (MFC) 11 for adjusting the amount of purge nitrogen gas is provided, and the controller 12 for driving the exhaust flow rate automatic adjustment valve unit 10 and the mass flow controller 11 is connected to the reactor 2. It is installed to be connected to the gate door (7) by gradually closing the exhaust flow rate automatic control valve 10 before the gate door 7 is opened to adjust the pressure in the reactor (2) in the same manner as the outside of the gate door (7) Opening and closing reaction furnace (2) It is configured to remove the pressure difference, and the same reference numerals for the same parts as those of the conventional configuration to the figures.

That is, in the present invention, in opening and closing the gate door 7 to load or unload the wafer 4, the exhaust flow rate automatic control valve 10 is gradually closed before the gate door 7 is opened, thereby allowing the reaction path. (2) It is characterized by adjusting the pressure in the same way as the outside.

At this time, since the purge nitrogen gas flows into the reactor 2 about 59000 cc / min, the amount of nitrogen gas for purge is adjusted to 59000 cc / min by adjusting the mass flow controller 11 in proportion to the degree of closing the exhaust flow rate automatic control valve 10. It should be gradually reduced to about 10,000cc / min.

Reducing the amount of nitrogen gas for purging as described above is to prevent the flow of air flowing out through the gate (5) by a large amount of purge nitrogen gas by closing the exhaust flow automatic control valve (10).

Hereinafter, the operation and effects of the internal pressure regulator of the present invention configured as described above will be described.

It should be noted that the basic operation of the atmospheric chemical vapor deposition apparatus, that is, the operation of loading the wafer 4 into the reactor 2, and unloading through the gate 5 after the process is the same as in the prior art.

As shown in FIG. 4, the exhaust flow rate automatic control valve 10 is gradually closed using the controller 12 before opening the gate door 7 to load or unload the wafer 4, as shown in FIG. By controlling the mass flow controller 11 for supplying purge nitrogen gas at the same time as reducing the exhaust pressure in the reactor (2) by reducing the amount of nitrogen gas from 59000cc / min to 10000cc / min while automatically adjusting the exhaust flow rate valve (10) The gate door 7 is opened and closed and the wafer 4 is loaded and unloaded by the time of closing.

That is, the flow of air through the gate 5 is removed by opening the gate door 7 in the state where the pressure inside and outside the reactor 2 is the same.

For reference, referring to the overall operation of the atmospheric pressure chemical vapor deposition equipment in which the device of the present invention is operated, first, the loading switch is turned on and then the controller 12 is operated to adjust the internal pressure of the reactor 2 to the same state as the external pressure. Then, the gate door 7 is opened to load the wafer 4, the gate door 7 is closed, the pressure inside the reactor 2 is reduced to the process conditions, and the process is performed. After the process is completed, the unloading switch is turned "on" and the controller 12 is operated again to adjust the internal pressure of the reactor 2 to the external pressure atmosphere, and then open the gate door 7 to open the wafer ( After unloading 4), the gate door 7 is closed again, and the inside of the reactor 2 is reduced to the process atmosphere to complete one cycle of the process.

As described in detail above, when employing the reactor internal pressure regulator according to the present invention, in the opening and closing of the gate door for loading and unloading the wafer, the reactor internal pressure is adjusted to be equal to the external pressure. In this state, the gate door is opened so that the rapid air flow between the inside and the outside of the reactor is removed, so that the powder, which is a by-product of the process attached to the gate, does not flow into the reactor, and as a result, the powder is introduced into the reactor. It is possible to prevent the deposition film non-uniformity and product defects caused by the inflow, it is possible to expect a yield improvement due to the reduction of defective rate.

Claims (1)

A mass flow controller 11 is installed in the exhaust pipe 6 of the reactor 2 to adjust the amount of purge nitrogen gas at the nitrogen inlet 1 of the reactor 2. And the controller 12 for driving the exhaust flow rate automatic control valve 10 and the mass flow controller 11 to be connected to the gate door 7 of the reactor 2 to open the gate door 7. Reactor internal pressure control device of the atmospheric pressure chemical vapor deposition equipment, characterized in that the pressure in the reactor (2) is configured to maintain the same as the outside by slowly closing the exhaust flow automatic control valve (10) before.