KR200365533Y1 - Furnace of low temperature chemical vaper deposition equipment - Google Patents

Abstract

The present invention discloses a reactor of a low pressure image vapor deposition (LP-CVD) apparatus.

The present invention is a reactor of a low pressure image vapor deposition apparatus having an outer tube, an inner tube and a manifold, wherein the manifold is a first manifold supporting the outer tube and a second manifold supporting the inner tube. The second manifold is configured to be movable up and down, and the inner tube is loaded / unloaded into the reactor.

Therefore, during wafer loading / unloading of the reactor of the low pressure image vapor deposition apparatus, the inner tube moves together while enclosing the periphery of the boat so that the inner side when exposed to a rapid temperature change between the high temperature reactor and the room temperature loading region As the tube acts as a buffer, delaying the cooling rate / heating rate of the wafer may bring about an effect of preventing the wafer from bending or cracking.

Description

FURNACE OF LOW TEMPERATURE CHEMICAL VAPER DEPOSITION EQUIPMENT}

The present invention relates to a furnace of a vertical low pressure chemical vapor deposition (LP-CVD) apparatus. More specifically, the wafer is moved with an inner tube during wafer loading / unloading in a reactor by rapid temperature change. A reactor of a low pressure chemical vapor deposition apparatus in which a wafer is not thermally damaged.

Chemical Vapor Deposition (CVD) used in a semiconductor process is to decompose a gaseous compound and form a thin film or epi layer on a semiconductor substrate by chemical reaction. The process of forming the thin film is mainly performed by drawing gas from the outside into the reactor without using a material on the silicon wafer. In order to decompose the introduced reaction gas, heat, plasma energy by RF power, light energy of laser or ultraviolet light is used, and the reaction of atoms or molecules decomposed by heating of the substrate or the physical properties of the formed thin film may be controlled. do.

CVD is classified into atmospheric pressure chemical vapor deposition (AP-CVD) and low pressure or reduced pressure chemical vapor deposition (LP-CVD) apparatus according to the degree of vacuum in the reactor during the process.

In LSI and VLSI circuits, the gate width is reduced, the thickness of the thin film is reduced, the film thickness uniformity is required, and LP-CVD is mainly used for the low temperature process to prevent the device from being destroyed by the existing junction depth or side diffusion. do.

Low pressure in the reactor reduces convection and increases the gas diffusion rate. In general, it helps to achieve uniform growth. In addition, the reduced pressure system improves the characteristics and uniformity of automatic doping.

Heating methods for the reactor include radiant heating, induction heating, and heating through hot walls.

1 is an exploded perspective view showing the basic configuration of a conventional LP-CVD reactor.

The reactor 10 is placed in a resistive heating furnace 1, i.e. a heater, consisting of three typical zones, and the wafers W are aligned vertically inside the reactor 10, aligned with the boat 2. Reactor 10 has a vacuum seal at the end to form a low pressure. Reaction products and unused gases are exhausted out of the device by a mechanical vacuum pump (VP).

The reactor 10 is formed of a cylindrical tube made of quartz to withstand high temperatures, and the inner tube 11 in which the actual wafer deposition process is performed, and the reactor 10 in a reduced pressure while protecting the inner tube 11. It consists of the outer tube 12 which blocks | blocks the atmosphere from the atmosphere, and the manifold 13 which supports the inner side groove 11 and the outer tube 12. As shown in FIG.

In the manifold 13, a vacuum port 14 for extracting air in the reactor 10 and a gas injection tube 15 for supplying reactant gas and inert gas are respectively formed in the reactor 10. have.

Below the manifold 13, the pedestal 3 conveyed in the vertical direction is provided. On the pedestal 3 is placed a boat 2 on which the wafers are stored and loaded / unloaded into the reactor 10. In addition, the pedestal 3 is hermetically coupled to the lower portion of the manifold 13 to maintain the vacuum state inside the reactor 10.

The reaction gas and the inert gas flow through the space between the inner wall of the wafer W and the inner tube 11 and diffuse into the narrow space between the wafer W, and the diffused gas is the outer wall and outer tube of the inner tube 11. It flows through the space between the inner walls of (12) and is discharged to the vacuum port 14.

Radiant heat generated in the resistance heating furnace 1 passes through the outer tube 12 and the inner tube 11 to determine the diffusion temperature of the reaction furnace 10.

However, in the reactor 10 of the conventional low pressure image vapor deposition apparatus having such a structure, a wafer is loaded / unloaded into the reactor 10 by the boat 2, and the temperature of the reactor 10 and the temperature of the reactor 10 are different. The difference was so great that the wafers were exposed to rapid temperature changes, causing thermal damage.

In more detail, in order to perform the diffusion process in the reactor 10 of the low pressure vapor deposition apparatus, the wafer is loaded into the reactor 10 while the reactor 10 maintains the atmosphere of at least 750 ° C. or more. After the diffusion process, the wafer is unloaded from the reactor 10 at a similar temperature. At this time, the loading area around the reactor 10 is maintained at room temperature.

Therefore, when the wafer is unloaded after the completion of the process, the wafer is heated in a high temperature atmosphere of 750 ° C. or higher and suddenly comes into contact with air at room temperature, and the wafer undergoes a sudden drop in temperature. Such a change in temperature can cause the wafer to crack or bend immediately. This change in temperature occurs equally during wafer loading.

Therefore, the present invention is designed to solve such a conventional problem, and can prevent the wafer from being thermally damaged by the temperature difference between the inside and the outside of the reactor while the wafer is loaded / unloaded into the reactor by the boat. Its purpose is to provide a reactor for low pressure vapor deposition apparatus.

The present invention for achieving the above object in the reactor of the low pressure image vapor deposition apparatus provided with the outer tube, the inner tube and the manifold, the manifold to support the outer tube and the first manifold, It is composed of a second manifold for supporting, the second manifold is configured to be movable in the vertical direction, characterized in that the inner tube is loaded / unloaded in the reactor.

The above object and various advantages of the present invention will become more apparent from the preferred embodiments of the present invention described below with reference to the accompanying drawings by those skilled in the art.

1 is an exploded perspective view showing a conventional LP-CVD reactor;

2 is an exploded perspective view illustrating an LP-CVD reactor according to the present invention;

3 is a use state according to the present invention.

<Description of the code for the main part of the drawing>

10; Reactor

11; Inner tube

12; Outer tube

20; Manifold

21; First manifold

22; Second manifold

Hereinafter, with reference to the accompanying drawings illustrating a preferred embodiment of the present invention as follows.

Figure 2 is a perspective view showing a reactor of a low pressure chemical vapor deposition apparatus according to the present invention.

As shown, the reactor 10 is placed in a resistive furnace 1 consisting of three zones typical for uniform radiant heat transfer, and the wafers W aligned with the boat 2 to the reactor 10. Closely and vertically placed inside. The inside of the reactor 10 has a vacuum seal at the end to form a low pressure, the reaction product and the unused gases are exhausted out of the device by a mechanical vacuum pump (VP).

The reactor 10 is formed of a cylindrical tube made of quartz to withstand high temperatures, and the inner tube 11 in which the actual wafer deposition process is performed, and the reactor 10 in a reduced pressure while protecting the inner tube 11. It consists of the outer tube 12 which blocks | blocks the atmosphere from the atmosphere, and the manifold 20 which supports the inner side groove 11 and the outer tube 12.

The manifold 20 is configured by separating the first manifold 21 supporting the outer tube 12 and the second manifold 22 supporting the inner tube 11 from each other. 22 is configured to be movable in the vertical direction. Therefore, the inner tube 11 supported by the second manifold 22 is moved up and down to be loaded / unloaded into the reactor 10.

According to the exemplary drawing, in order to move the second manifold 22 in the vertical direction, the guide rod 23 and the threaded threaded thread 24 formed in the direction parallel to the vertical reactor 10 are installed around the reactor. One end of the second manifold 22 is coupled to the guide 23 and the screw rod 24. When the screw rod 24 is rotated by a driving motor (not shown), the rotational movement of the screw rod 24 is converted into a linear movement of the second manifold 22 to thereby perform vertical movement.

Since the inner tube 11 is supported by the second manifold 22, it moves with the second manifold 22.

On the other hand, the first manifold 21 is formed with a vacuum port 14 for extracting air in the reactor 10, the second manifold 22 is a reaction gas and inert in the reactor 10 Gas injection pipes 15 for supplying gas are respectively formed.

Below the 2nd manifold 22, the pedestal 3 conveyed in a vertical direction is provided. On the pedestal 3 is placed a boat 2 on which the wafers are stored and loaded / unloaded into the reactor 10. In addition, the pedestal 3 is hermetically coupled to the lower portion of the manifold 20 so as to maintain the vacuum state inside the reactor 10.

The reaction gas and the inert gas flow through the space between the inner wall of the wafer W and the inner tube 11 and diffuse into the narrow space between the wafer W, and the diffused gas is the outer wall and outer tube of the inner tube 11. It flows through the space between the inner walls of (12) and is discharged to the vacuum port 14.

Radiant heat generated in the resistance heating furnace 1 passes through the outer tube 12 and the inner tube 11 to determine the diffusion temperature of the reaction furnace 10.

Hereinafter, the operation and effects according to the present invention will be described.

3 is an operation diagram showing a state before the wafer is loaded / unloaded into the reactor.

First, when the wafer W performs the diffusion process in the reactor 10 and then unloads into the loading area, the pedestal 3 descends in the vertical direction to open the bottom surface of the second manifold 22 while the pedestal 3 is opened. The boat (2) and the wafer (W) stored in the boat (2) mounted on the vertical direction starts to exit the reactor (10). After a while, the second manifold 22 is lowered vertically when the wafer W begins to be exposed out of the reactor 10. The inner tube 11 supported thereon by the lowering of the second manifold 22 is also lowered and unloaded in the reactor 10.

Preferably, the inner tube 11 is lowered together while surrounding the circumference of the boat 2 along the boat 2 exiting the reactor 10. Therefore, the wafer W stored in the boat 2 is drawn out of the reactor 10 in a state surrounded by the inner tube 11.

This serves to primarily block the inner tube 11 heated to a similar temperature from the wafer W heated at a high temperature in the reactor 10 to be in direct contact with air at room temperature in the loading area. (W) prevents thermal damage.

That is, when the wafer W is exposed to a rapid temperature change from the high temperature reactor 10 to the loading region at room temperature, the inner tube 11 serves as a buffer so that the cooling rate of the wafer W is delayed. W) prevents bending or cracking due to rapid temperature change.

After a while, after the cooling of the wafer W is completed, the second manifold 22 is raised so that the inner tube 11 enters the reactor 10, and the boat 2 and the wafer W are the same as in the related art. Is discharged.

On the other hand, during the movement of the second manifold and the inner tube 11, it can be considered that the air flow in the room temperature to the upper and lower portions of the inner tube 11 opened, which is generally the air flow of the loading area in the horizontal direction And the upper and lower portions of the boat (2) has a dummy wafer (W) and the pedestal (3) because the enormous amount of air inlet serves to block to some extent does not cause a big problem in the process.

So far, the operation and effect of the reactor 10 according to the present invention have been described when the wafer W is unloaded, but such an operation and effect may also be applied when the wafer W is loaded.

That is, when the wafer W is loaded into the high temperature reactor 10 in the loading region at room temperature, the wafer W is exposed to a rapid temperature change, in which case the wafer W reacts to be loaded into the reactor 10. When located below the furnace 10, the inner tube 11 heated to a high temperature is lowered to surround the wafer W to preheat the wafer W in advance. After a while, the preheated wafer W and the inner tube 11 are loaded together into the reactor 10, where the wafer W has a relatively low temperature inside the hot gas delivered from the outer tube 12. Since it is primarily buffered by the tube 11 and then transferred to the wafer W, thermal damage of the wafer W may be prevented.

On the other hand, in a preferred embodiment of the present invention is merely illustrative of the reactor 10 applied to the low-pressure image vapor deposition apparatus is not limited to this can be applied to both reactors with inner and outer tubes, Those skilled in the art to which the present invention pertains may make modifications and variations to the present invention without changing the subject matter of the present invention.

Therefore, according to the present invention, the inner tube moves together while enclosing the boat's periphery during wafer loading / unloading in the reactor of the low pressure image vapor deposition apparatus so as to prevent rapid temperature change between the high temperature reactor and the normal temperature loading region. When exposed, the inner tube plays a buffer role, thereby delaying the cooling rate / heating rate of the wafer, which may have an effect of preventing the wafer from bending or cracking.

Claims (2)

In a reactor of a low pressure image vapor deposition apparatus provided with an outer tube, an inner tube, and a manifold, The manifold includes a first manifold supporting an outer tube and a second manifold supporting an inner tube, wherein the first manifold and the second manifold are separated from each other, and the second manifold is disposed up and down. Configured to move in a direction, After the wafer has performed the diffusion process in the reactor, when unloading into the loading zone, the boat and the wafer stored in the boat descend in the reactor and begin to be exposed from the reactor; The manifold and the inner tube supported thereon descend together, When the wafer is loaded into the reactor at high temperature in a loading zone of room temperature, when the wafer is positioned below the reactor to be loaded into the reactor, the inner tube heated to a high temperature is lowered to move around the wafer. The preheated wafer is enclosed in advance, and then the preheated wafer, the inner tube and the second manifold are raised together into the reactor. The low pressure image vapor deposition apparatus according to claim 1, wherein the vertical movement of the second manifold comprises a guide rod and a threaded threaded rod in a direction parallel to the reactor. Reactor.