KR20100107351A - Chemical vapor deposition appratus - Google Patents

Abstract

PURPOSE: An apparatus for a chemical vapor deposition process is provided to improve the efficiency of the deposition process by depositing thin films using two or more processing gases. CONSTITUTION: A stage(20) is installed in a chamber(10). Wafers are loaded on the stage. A first shower head(111) is installed on the upper side of the chamber. A first gas supplying line(110) supplies a first processing gas through the first shower head. A second shower head(121) is installed to the stage. A second gas supplying line(120) supplies a second processing gas through the second shower head.

Description

Chemical Vapor Deposition Equipment {CHEMICAL VAPOR DEPOSITION APPRATUS}

The present invention relates to a chemical vapor deposition apparatus, and more particularly to a chemical vapor deposition apparatus for depositing a thin film using two or more process gases.

In general, a chemical vapor deposition apparatus injects a highly reactive process gas into a chamber, and activates the process gas using light, heat, plasma, microwave, X-ray, or electric field to form a high quality thin film on a wafer. It is a device configured to.

Recently, a metal organic compound vapor deposition apparatus using a metal organic compound vapor as a process gas has been used. In this case, the step coverage is excellent, and damage to the substrate or the crystal surface is reduced. In addition, the deposition process is relatively fast, it is possible to shorten the process time. Therefore, it has been used in the manufacture of image display devices such as electronic displays and graphics, and memory devices using ferroelectric materials.

In general, such a chemical vapor deposition apparatus is supplied with a plurality of process gases into the chamber in which the wafer is located. Then, the deposition is performed on the wafer while the reaction is performed between the process gases.

However, in the related art, two or more kinds of process gases are supplied from adjacent positions, and a predetermined particle is generated while the reaction is performed between the process gases before reaching the wafer. In this case, while particles were generated in the air before being deposited on the wafer, it was difficult to provide a source of various types of particle sources to ensure stable processability.

The present invention may provide a chemical vapor deposition apparatus in which the respective process gases do not react beforehand, and the deposition may occur while the reaction of the process gases is started on the upper surface of the wafer.

In order to achieve the above object, the present invention provides a first gas supply line for supplying a first process gas through a chamber, a stage installed inside the chamber, on which a wafer is seated, and a first shower head installed above the chamber. In addition, the chemical vapor deposition apparatus may include a second gas supply line configured to supply a second process gas through a second shower head installed on an upper surface of the stage.

Here, the second gas supply line is formed with a flow path through which the second process gas is supplied to the inside of the stage, and the second process gas supplied along the flow path of the upper surface of the stage through the injection hole of the second shower head. It is preferable to be configured to spray in the outward direction.

On the other hand, the above object is a chamber, a stage installed inside the chamber, the wafer is seated, a first gas supply line for supplying a first process gas to the stage from the upper side of the chamber, and lower than the first gas supply line It can also be achieved by a chemical vapor deposition apparatus comprising a second gas supply line for supplying a second process gas to the top of the stage at a height.

In this case, the second gas supply line preferably supplies a second process gas from the lower side of the chamber to the upper surface of the stage.

The second gas supply line includes a second flow path formed inside the stage and a second shower head installed on an upper surface of the stage and supplying a second process gas supplied through the second flow path to the upper surface of the stage. It is desirable to be.

Here, the second shower head may be formed with a plurality of injection holes in the outward direction of the stage.

On the other hand, the second gas supply line may further include a heater for heating the second process gas to the outside of the second flow path.

And, the lower side of the stage is provided with a rotating shaft for rotating the stage, the second flow path is preferably formed along the inner side to the rotating shaft.

On the other hand, the exhaust port is formed on the outside of the stage, when the first and the second process gas in the outward direction along the upper surface of the stage, it can be configured to discharge the process gas through the exhaust port to the outside have.

According to the present invention, since the reaction of each process gas occurs adjacent to the position where the wafer is seated, it is possible to improve the efficiency deposited on the wafer. Unnecessary particle generation can be prevented, and it is possible to improve the quality of the wafer.

Hereinafter, with reference to the drawings, it will be described in detail with respect to the chemical vapor deposition apparatus according to a preferred embodiment of the present invention.

In the present embodiment, a metal organic chemical vapor deposition apparatus (MOCVD) using an organic metal compound as a gas is described as an example. However, the present invention is not limited thereto, and of course, the present invention may be applied to another type of chemical vapor deposition apparatus such as HVPE (Hydride Vapor Phase Epitaxy) and PECVD (Plasma Enhanced Chemical Vapor Deposition).

1 is a cross-sectional view showing a cross section of a chemical vapor deposition apparatus according to a preferred embodiment of the present invention.

As shown in FIG. 1, the chemical vapor deposition apparatus includes a chamber 10, a stage 20 on which a wafer is seated, and first and second gas supply lines 110 to which first and second process gases are supplied. , 120). Hereinafter, each component will be described in detail.

The chamber 10 forms the exterior of the chemical vapor deposition apparatus according to the present invention, and forms a space in which the deposition process is performed. At this time, the chamber 10 is preferably configured to increase the deposition efficiency by maintaining the airtight and the outside except for the flow path that is actively controlled during deposition. In addition, it is more preferable that the insulation is made of a good material so as to create a high temperature environment therein.

Meanwhile, the stage 20 may be provided inside the chamber 10. The wafer on which the deposition process is performed is seated on the upper surface of the stage 20. In this case, a plurality of seating parts 23 (see FIG. 2) may be provided on the upper surface of the stage 20 so that a plurality of wafers may be simultaneously deposited. The stage 20 may be rotatably installed inside the chamber 10 by a predetermined rotation shaft 22. At this time, when the position at which the process gas is introduced into the chamber 10 is biased to one side, the stage may be rotated to a position corresponding thereto to uniformly deposit on each wafer.

In addition, a plurality of hot wires 21 may be installed inside the stage 20. In general, a chemical vapor deposition method heats a wafer above a predetermined temperature and supplies a high vapor pressure organometallic compound process gas to form a thin film. Therefore, in the present exemplary embodiment, a heating block may be formed by installing a plurality of heating wires 21 adjacent to the upper surface of the stage 20 on which the wafer is seated.

Meanwhile, the first and second gas supply lines 110 and 120 supply the first process gas and the second process gas to the inside of the chamber 10 during the deposition process. In this embodiment, trimethylgallium (TMGa) and ammonia (NH ₃ ) can be used as the first and second process gases. Specifically, trimethylgallium is used as the first process gas and ammonia as the second process gas. However, this is one embodiment and the present invention is not limited to the type of the process gas.

 Therefore, when the first and second process gases are supplied into the chamber 10, gallium (Ga) of trimetal gallium and nitrogen (N) of ammonia react to form particles of gallium nitride (GaN). The gallium nitride may be deposited on a wafer.

In this case, it is preferable that the first gas supply line 110 and the second gas supply line 120 respectively supply the first process gas and the second process gas at different positions. Further, it is preferable to set the positions of the first and second gas supply lines 110 and 120 such that the first and second process gases supplied into the chamber 10 meet on the upper surface of the stage 20 to cause a reaction. Do. In this case, the reaction occurs before the first and second process gases reach the wafer, thereby reducing the formation of particles and simultaneously improving the deposition efficiency.

For example, the first gas supply line 110 and the second gas supply line 120 may supply the first process gas and the second process gas into the chamber at different heights. As shown in FIG. 2, the first gas supply line 110 may supply a first process gas to the upper side of the chamber 10, and the second gas supply line 120 may be lower than the stage 20. From the second process gas can be supplied along the upper surface of the stage (20). Accordingly, the first and second process gases meet on the upper surface of the stage 20, and a chemical reaction occurs, and the resulting gallium nitride (GaN) may be deposited on the wafer seated on the upper surface of the stage 20. .

In detail, the first gas supply line 110 may include a first flow path 113 supplied to the upper side of the chamber 10, a backing plate 112 supplied with the first process gas from the first flow path, and a backing plate. It may be configured to include a first shower head 111 mounted on the 112 to inject a process gas.

On the first shower head 111 or the backing plate 112, it is possible to selectively include a configuration such as a separate rib, hot wire, or diffuser to adjust the state and dispersion of the first process gas.

The second gas supply line 120 may include a second flow path 123 formed inside the stage 20 and a second shower head 121 installed on the upper surface of the stage 20. Here, the second process gas supplied from the lower side of the chamber 10 is supplied along the second flow path 123 formed to penetrate the inside of the stage 20, and then through the second shower head 121. It may be injected into the inside of (10). In this case, when the stage 20 is configured to be rotatable by the inner rotation shaft 22, the second flow path 123 may be installed to be fixed to the inner side of the rotation shaft 22.

On the other hand, when using trimetal gallium (TMGa) and ammonia (NH ₃ ) as the first and second process gas as in this embodiment, each process gas, especially ammonia (NH ₃ ) is heated to a high temperature state between the process gases The chemical reaction can proceed easily.

In this embodiment, as shown in FIG. 2, a heater is provided outside the second flow path 123. Therefore, the second process gas passing through the second flow path 123 may be heated to a temperature of 300 ° C. to 500 ° C. or more and decomposed into an ionic or radical state, and may be supplied into the chamber 10. Therefore, it can react easily with a 1st process gas.

In the present embodiment, the relatively heavy trimethyl gallium (TMGa) is configured to be supplied from the upper side downward along the first gas supply line 110, and relatively light ammonia (NH ₃ ) is supplied to the second gas supply line 120 Followed was configured to be fed from the bottom to the top. However, the present invention is not limited thereto, and may be configured using different kinds of supply gases, or may be configured by changing the supply positions of the trimethyl gallium and ammonia. In this case, since ammonia is supplied from the supply line above the chamber 10, the position of the heater may also be changed to the upper side of the chamber 10 so that preliminary heating may be performed on a path through which ammonia is supplied.

FIG. 2 is a schematic diagram illustrating a flow path of a process gas supplied to the stage of FIG. 1.

As shown in FIG. 2, the second gas supply line 120 may include a second shower head 121 formed to be exposed to the upper surface of the stage 20. The second shower head 121 may be formed of a cap-shaped member installed inside the upper surface of the stage 20.

In this case, the second shower head 121 may include a plurality of injection holes 122 formed in the outer direction of the stage 20. Each injection hole 122 is connected to the second flow path to inject a second process gas supplied along the second flow path. In this case, the injected second process gas may proceed to the outside of the stage 20 along the upper surface of the stage 20 as shown in FIG. 2.

That is, as shown in FIG. 2, in the present embodiment, the first process gas, trimetal gallium (TMGa) and the second process gas, ammonia (NH ₃ ), proceed along different paths, and the upper surface of the stage, That is, the first contact with the portion adjacent to the injection hole 122 of the second shower head 121. In addition, the reaction occurs while the first and second process gases advance together from the inside to the outside of the stage 20. That is, while gallium nitride (GaN) is generated, deposition is performed on the wafer seated on the upper surface of the stage 20, and the remaining first and second process gases proceed to the outside of the stage 20.

On the other hand, the first and second process gas proceeds to the outside of the upper surface of the stage 20 so that the first and second process gas can be continuously introduced may be exhausted to the outside through the exhaust port (30). In addition, it is possible to include a shielding member 40 for shielding the space below the exhaust port 30 so as to prevent unnecessary waste of the process gas to fill the space inside the chamber 10.

As described above, according to the present invention, each process gas is supplied into the chamber 10 and proceeds along a different path, and then proceeds from the position where the deposition is performed, that is, reaching the upper surface of the stage 20. The reaction occurs while sharing. Therefore, the particles formed by the reaction between the process gases contribute to the deposition on the wafer, it is possible to improve the process efficiency.

In the present embodiment, a chemical vapor deposition apparatus using two process gases has been described, but the present invention is not limited thereto. In addition to this, even when a plurality of process gases are used, the present invention can be applied by configuring a path such that each process gas forms particles at a position adjacent to the wafer.

1 is a cross-sectional view showing a cross section of a chemical vapor deposition apparatus according to a preferred embodiment of the present invention,

FIG. 2 is a schematic diagram illustrating a flow path of a process gas supplied to the stage of FIG. 1.

Claims (9)

chamber; A stage installed inside the chamber to seat a wafer; A first gas supply line supplying a first process gas through a first shower head installed above the chamber; And, And a second gas supply line for supplying a second process gas through a second shower head installed in the stage. The method of claim 1, The second gas supply line has a flow path through which the second process gas is supplied to the inside of the stage, and the second process gas supplied along the flow path is directed outwardly of the upper surface of the stage through the injection hole of the second shower head. Chemical vapor deposition apparatus, characterized in that for spraying. chamber; A stage installed inside the chamber to seat a wafer; A first gas supply line supplying a first process gas to the stage from an upper side of the chamber; And, And a second gas supply line for supplying a second process gas to the stage at a height lower than that of the first gas supply line. The method of claim 3, The second gas supply line is a chemical vapor deposition apparatus, characterized in that for supplying a second process gas from the lower side of the chamber to the upper surface of the stage. The method of claim 3, The second gas supply line includes a second flow path formed inside the stage and a second shower head installed on an upper surface of the stage and supplying a second process gas supplied through the second flow path to the upper surface of the stage. Chemical vapor deposition apparatus characterized in that. The method of claim 5, The second shower head is a chemical vapor deposition apparatus, characterized in that a plurality of injection holes are formed in the outward direction of the stage. The method of claim 5, The second gas supply line further comprises a heater for heating the second process gas to the outside of the second flow path. The method of claim 5, The lower side of the stage is provided with a rotating shaft for rotating the stage, the second flow path is a chemical vapor deposition apparatus, characterized in that formed along the inner side to the rotating shaft. The method of claim 5, When the exhaust port is formed on the outside of the stage, the first and second process gas in the outward direction along the upper surface of the stage, the process gas is discharged to the outside through the exhaust port Vapor deposition apparatus.

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