KR100585046B1 - Plasma processing apparatus - Google Patents

Abstract

According to an aspect of the present invention, there is provided a plasma processing apparatus for generating a plasma in a vacuum chamber to perform a predetermined treatment on a substrate, the upper electrode being provided above the chamber and supplying a process gas into the chamber. The upper electrode is separated into an inner and an outer side, and a radial branching hole is formed on each circumferential surface thereof, and a gas distribution part for adjusting the opening area of the branching hole by rotating any one of the inner and outer sides is provided. A plasma processing apparatus is provided.

Plasma processing apparatus, upper electrode, inner and outer distribution, inner and outer branches, driving means

Description

Plasma processing apparatus

1 is a cross-sectional view schematically showing a conventional plasma processing apparatus.

FIG. 2 is a side cross-sectional view illustrating the upper electrode of FIG. 1.

3 is a side cross-sectional view illustrating an upper electrode of a plasma processing apparatus according to an embodiment of the present invention.

4 is a plan sectional view showing a distribution part of the upper electrode of the plasma processing apparatus.

5A and 5B are partially enlarged views illustrating a rotation state of a distribution part corresponding to “A” of FIG. 4.

<Explanation of symbols for the main parts of the drawings>

120: upper electrode 121: housing

122: gas passage 124: inner distribution

125: inner branch 126: outer distribution

127: outer branch opening 128: gas diffusion plate

140: indicator 141: position adjustment block

142: spring

The present invention relates to a plasma processing apparatus, and more particularly, to a plasma processing apparatus having an upper electrode for providing a process gas into the process chamber.

Referring to the process of performing plasma processing on the above-described semiconductor wafer or liquid crystal substrate, first, a plurality of semiconductor wafers or liquid crystal substrates (hereinafter referred to as "substrates") stacked in a substrate storage device (hereinafter referred to as "cassette") are transport robots. Carry in or out by means of a load lock chamber, which circulates vacuum and atmospheric pressure, and pumps the inside of the load lock chamber into a vacuum state to make a vacuum, and then transfer means. In operation to move the substrate into the transfer chamber.

The transfer chamber to which the substrate is transferred is in communication with a plurality of process chambers that maintain a vacuum state, and the transfer chamber carries in and out of each process chamber through transfer means, where each process chamber The substrate brought into is placed on the mounting table positioned on the upper part of the lower electrode, the process gas is introduced through the micro holes formed in the lower part of the upper electrode, and the upper and lower electrodes are externally supplied with the introduced gas. It causes an electrical discharge to perform a plasma process on the surface of the substrate.

The upper and lower electrodes of the above-described process chamber are respectively installed above and below the inside of the chamber, and insulators are provided on both sides of the lower electrode on which the substrate, which is a target of plasma processing, is loaded. The above-mentioned electrode is generally aluminum, and is a relatively inexpensive material for processing semiconductors, and is widely used, and chemical reaction and high voltage of plasma formed by discharge of gas introduced into the electrode according to high voltage applied between upper and lower electrodes. Protect each electrode from

In addition, since the plasma process may cause corrosion to aluminum, a relatively inert ceramic material such as an aluminum oxide (Al 2 O 3) coating is used to protect the surface of the electrode made of aluminum.

In the conventional plasma processing apparatus, as shown in FIG. 1, a shower head having a process chamber 10 in which process processing is performed therein and an upper portion of the process chamber 10 described above, wherein a process gas is injected to a substrate at a lowermost end thereof. An upper electrode 20 provided with 25 and a lower electrode 30 provided below the upper electrode 20 and spaced apart from each other are loaded.

The above-mentioned upper electrode 20 is coupled to the housing 21 which is opened downward, the gas movement path 22 which is coupled to the central portion of the housing 21 and moves outside process gas therein, and the gas movement path The first gas diffusion plate 23 coupled to the central portion of the housing 21 described above, which moves the gas introduced from the gas flow path 22 downward and diffuses the first gas diffusion plate described above. A second gas diffusion plate 24 having a space spaced apart from the plate 23 and provided below and secondly diffusing the gas diffused from the first gas diffusion plate 23 to diffuse downward; It is comprised by the shower head 25 provided under the diffuser plate 24, and finally injecting a process gas to a board | substrate.

The above-described first gas diffusion plate 23 is formed in a plate shape having an appropriate length and perforations are arranged on the upper surface thereof at appropriate intervals. The second gas diffusion plate 24 corresponds to an inner length of the housing 21. Perforations are formed on one plate and arranged at appropriate intervals on the upper surface thereof, and the above-described shower head 25 has a plate shape corresponding to the inner length of the housing 21 similar to the above-described second gas diffusion plate 24. Perforations are arranged at appropriate intervals.

However, the process gas introduced through the above-described gas flow path 22 passes through the perforation of the first gas diffusion plate 23, the perforation of the second gas diffusion plate 24, and the perforation of the final shower head 25. However, there is a problem that the plasma is not uniform because it is impossible to control the amount of gas injected into the perforations when injected to the substrate.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object thereof is to provide a plasma processing apparatus capable of controlling the amount of gas supplied by adjusting the size of a distribution unit in which process gas is distributed downward and both sides.

In order to achieve the above object, the present invention provides a plasma processing apparatus for generating a plasma inside a chamber in a vacuum state to perform a predetermined treatment on a substrate, the upper portion of which is provided above the chamber to supply a process gas into the chamber; And an electrode, wherein the upper electrode is separated into an inner side and an outer side, and a radial branching hole is formed on each circumferential surface thereof to rotate one of the inner side and the outer side to adjust the opening area of the branching hole. Is provided, when any one of the inner and outer distribution portions of the gas distribution portion provided in the upper electrode is rotated, the inner and outer branching portions formed radially in the inner and outer distribution portions intersect and the opening area is adjusted. It is preferable because the amount of gas is adjusted to provide a suitable process gas according to the situation.

In addition, the gas distribution part of the present invention is composed of an inner distribution portion and an outer distribution portion, and the inner distribution portion is rotated in a state in contact with the outer distribution portion, respectively formed in the inner and outer distribution portions to adjust the amount of process gas supplied It is preferable to adjust the opening area of the inner and outer branches by turning any one of the gas distribution parts.

In addition, it is preferable that the driving means for rotating the inner distribution portion in the present invention is further provided.

In addition, the driving means in the present invention is driven manually or automatically, and in the case of manual, an indicator indicating the opening degree of the inner and outer branches is provided on the upper side of the inner and outer distribution portions, and is automatic. By controlling the rotation angle of the drive motor, the inner distribution part rotates by a proper angle from the gas movement path in the center, so that the driving means for imparting the rotational force during rotation of the inner distribution part is driven manually by the above-mentioned indicator. The degree of opening of the inner and outer branches can be adjusted by a driving motor which can control the amount of process gas by the operator's perception of the opening degree of the outer branch and, when driven automatically, can control the rotation angle of the inner distribution part. It is preferable because it adjusts.

In addition, when the driving means in the present invention is driven by a manual, the groove portion which is formed by an appropriate length in any one of the inner and outer distribution portion; A positioning block coupled to the dispensing part opposite to the distributing part in which the groove part is formed and moving in the groove part; One end is fixed to one side of the groove portion and the other end is fixed to the opposite position adjustment block; including, when the rotational distance when adjusting the opening area of the inner, outer branch is rotated by the diameter of the inner, outer branch Since the inner and outer branches are not in communication with each other, the movement distance is limited by the positioning block so as to limit the movement distance from the first concentrically communicated state to the non-communicated state at the groove part, and the intervening It is preferable to be able to return to the original position by the spring.

Hereinafter, an embodiment of the plasma processing apparatus of the present invention will be described with reference to the accompanying drawings.

Although the schematic structure of the plasma processing apparatus of the preferred embodiment of the present invention is not shown in the drawings, the process chamber, the upper electrode 120 provided above the inside of the process chamber, and the lower side opposed to the upper electrode 120 described above. Since the process chamber and the lower electrode have the same structure and function as those of the related art, the detailed description is omitted.

The upper electrode 120 is fixedly inserted into the housing 121 which is opened downward as shown in FIG. 3 and the center of the housing 121 described above, and external process gas is transferred to the upper electrode 120 described above. A gas distributor 122 which is an inflow passage, a gas distributor 123 that is coupled to the above-described gas passage 122 to distribute the introduced process gas in a downward direction and in both directions, and the above-described gas distributor ( A gas diffusion plate 128 provided on the bottom surface of the bottom surface 123 to diffuse the gas discharged in the lower direction and the both directions, and a shower head provided below the gas diffusion plate 128 to finally inject the gas to the substrate ( 129).

The gas distribution part 123 is composed of an inner distribution part 124 and an outer distribution part 126. The inner distribution part 124 is formed in a disk shape and has a stepped diameter with a small step on its bottom. An inner branch 125 in the longitudinal direction is formed in a radial direction, the outer circumferential portion 126 is the inner peripheral surface so that the bottom surface can be coupled to the stepped portion of the inner distributing portion 124 described above in a closed cylindrical shape The lower branch 127a having a diameter corresponding thereto and radially provided with an outer branch 127 concentric with the inner branch 125 of the inner distribution part 124 described above, and penetrating downward through the bottom center portion thereof is provided. Is formed.

Here, in the outer distribution part 126 in which the outer branch 127 is formed in the upper side of the outer branch 125 and 127 in the outer distribution part 126 combined with the inner distribution part 124 described above. An indicator 140 indicating an opening degree of the inner and outer branches 125 and 127 that intersects each other by rotating the inner distribution section 124 where the inner branches 125 are formed is provided. That is, the amount of process gas is adjusted by rotating the inner distributor 124 of the inner and outer distributors 124 and 126 using the above-described indicator 140.

In addition, among the above-described gas distribution unit 123, the inner distribution unit 124 is rotatable and the outer distribution unit 126 is fixed and provided with driving means for manually or automatically operating the above-described inner distribution unit 124. .

Here, when the above-mentioned driving means rotates the inner distribution part 124 of the gas distribution part 123 manually, the opening is opened by the indicator 140 provided above the inner and outer branch holes 125 and 127 mentioned above. It is possible to adjust the supply gas amount by adjusting the area, and when the above-described driving means automatically rotates the inner distribution unit 124 of the gas distribution unit 123, the above-described inner distribution unit 124 is driven by the driving motor ( Rotation by M, wherein the rotation angle of the above-described drive motor (M) is controlled by a motor control unit (not shown).

The gas diffusion plate 128 described above may move to the adjacent perforations of the process gas distributed in the inner and outer branches 125 and 127 and the lower branch 127a penetrating both sides of the gas distribution unit 123 described above. A plurality of perforations are formed at the proper position so that they can be formed.

The shower head 129 described above is finally passed before the process gas diffused and moved while passing through the gas diffusion plate 128 is injected onto the substrate, and the perforations are arrayed.

In more detail, the above-described gas distribution unit may be described as an inner distribution unit 124 provided inside and an outer distribution unit 126 provided in an inserted state outside the inner distribution unit 124. A radial inner branch 125 is formed at the stepped portion of the inner distribution part 124 described above, and a radial outer branch 127 is formed at the outer distribution part 126. The inner portion of the inner portion 124 is first rotated by the inner portion 124 of the outer portion 126 of the outer portion 126 by rotating the inner portion 124 by a driving means which is formed on the circumferential surface of the outer portion 126. When the mechanism 125 communicates concentrically with each other, and then rotates the inner distribution part 124 by applying rotational force by the driving means provided on the upper side, the center of the fixed outer branch 127 and the inner branch ( 125) the opening area is reduced as the centers are spaced apart from each other Air that is reduced as much as the moving amount of the process gas.

On the other hand, the reason for rotating the inner distribution unit 124 in the above-described outer distribution unit 126 is the inner side formed in the inner distribution unit 124 in the outer branch 127 formed in the outer distribution unit 126 described above. When the branch 125 is moved in one direction, the centers of the inner and outer branches 125 and 127 are spaced apart from each other, and the centers thereof are rotated by the diameter length of the branches 125 and 127. This is because the inner and outer branches 125 and 127 are not communicated with each other and the flow of the process gas is blocked so that the amount of gas can be adjusted according to the crossing amount of the inner and outer branches 125 and 127. In addition, in order to limit the rotation angle of the inner distributing portion 124 described above, an inwardly concave groove portion 126 'is formed at a predetermined position of the outer distributing portion 126, and within the length range of the groove portion 126'. It is coupled to the inner distributing portion 124 which is in contact with the movable positioning block 141, the one end of the spring 142 is fixed to the groove portion 126 'of the outer distributing portion 126 described above and the other end is the opposite position When the inner distribution part 124 is rotated by fixing to the adjustment block 141, the positioning block 141 coupled to the inner distribution part 124 is fixed to the groove part 126 ′ of the outer distribution part 126. When the spring 142 is compressed and rotates more than the diameter length of the outer branch 127 described above, the spring 142 is no longer moved by the compressed spring 142 and the inner and outer branches 125 and 127 are blocked from each other. The movement of gas is blocked. Here, if the above-mentioned rotational force of the inner distribution unit 124 is removed, it is returned to its original position by the restoring force of the spring 142 described above, and the outer branch holes 125 and 127 communicate with the first concentric state. (See FIGS. 5A and 5B, which are enlarged views of portion “A” of FIG. 4)

Therefore, in the plasma processing apparatus of the present invention, the process of introducing external process gas through the upper electrode in the process chamber may be performed through a gas movement path connected to the upper center of the upper surface of the upper electrode 120 as shown in FIGS. 3 and 4. The process gas introduced through 122 is introduced into the gas distribution unit 123 including the outer distribution unit 126 coupled to the inner distribution unit 124, where the upper center portion of the inner distribution unit 124 is described above. When driven automatically by the drive motor M, which is a driving means located in the inner branch 125 of the inner distribution portion 124 so as to be concentric with the outer branch 127 of the outer distribution portion 126. In order to reduce the amount of process gas discharged in communication, the driving motor M described above is driven to alternate the inner branch 125 from the outer branch 127 to reduce the opening area, thereby reducing the amount of gas passing through the reduced area. Supply is reduced The gas diffusion plate 128 provided below through the inner and outer branches 125 and 127 provided on both sides of the gas distribution unit 123 and the lower branch 127a formed at the bottom center of the outer distribution unit 126. It is moved to the perforations formed radially in the center and both sides of and passes through the shower head 129 located at the bottom is injected to the substrate.

Alternatively, when the driving means for rotating the above-described inner distribution unit 125 of the gas distribution unit 123 is driven automatically, it is necessary to reduce the amount of process gas as necessary, and thus, the above-mentioned inner and outer parts may be used. The above-mentioned outer branch 127 is provided in the upper side of the inner and outer branch holes 125 and 127 formed in the back part 124, 126 and shows the opening amount of these branch holes 125 and 127. In the formed outer distribution part 126, the inner distribution part 124 in which the above-mentioned inner branch 125 was formed is rotated manually, and the outer branch 127 and the inner branch 125 may be mutually staggered in the concentric state. As a result, the opening area is reduced and the amount of gas discharged is reduced. At this time, a groove 126 'is formed on the inner circumferential surface of the outer distribution part 126 so that the above-described inner distribution part 124 can move by a predetermined position. Inside so that the length of 126 'can be the moving distance The movement distance is limited by the positioning block 141 protruding from the back portion 124, but when the inner branch outlets 125 and 127 are to be positioned concentrically, one end is removed when the driving force is removed. It is fixed to one side of the other end is returned to the original position penetrated by the restoring force of the spring 142 fixed to the opposed positioning block 141.

Subsequently, the process gas having a reduced discharge amount is provided on both sides of the above-described gas distribution unit 123, and the lower branch opening 127a formed at the center of the bottom of the outer branch outlets 125 and 127 and the outer distribution unit 126. The gas is injected into the substrate through the shower head 129 positioned at the bottom of the gas diffusion plate 128 provided in the lower side and the holes formed in both radially.

Such a plasma processing apparatus of the present invention rotates the inner distribution part based on the outer distribution part of the gas distribution part communicated with the gas movement path when it is necessary to finally adjust the amount of process gas supplied to the substrate through the gas movement path. In the state where the outer branch of the outer distribution part and the inner branch of the inner distribution part are in concentric communication, the opening area is reduced by driving the driving means, and the reduced amount of gas is injected to the substrate through the reduced inner and outer branches. There is an effect that can form a plasma.

Claims (5)

A plasma processing apparatus for generating a plasma inside a chamber in a vacuum state to perform a predetermined treatment on a substrate. And an upper electrode provided at an upper side of the chamber to supply a process gas into the chamber. The upper electrode is separated into an inner and an outer side, and a radial branching hole is formed on each circumferential surface thereof, and a gas distribution part for adjusting the opening area of the branching hole by rotating any one of the inner and outer sides is provided. Plasma processing apparatus. The gas distribution unit of claim 1, And an inner distribution unit and an outer distribution unit, wherein the inner distribution unit rotates in contact with the outer distribution unit. The method of claim 2, And a driving means for rotating the inner distribution part. The method of claim 3, wherein the drive means, Driven manually or automatically, In the case of manual, an indicator indicating the opening degree of the inner and outer branch openings is provided on the upper side of the inner and outer distributing portions, In the case of automatic, the plasma processing apparatus, characterized in that for controlling the rotation angle of the drive motor to rotate the inner distribution portion by a proper angle from the gas flow path in the center. The method of claim 4, wherein When the driving means is driven by a manual, the groove portion is formed by a suitable length in any one of the inner, outer distribution portion; A positioning block coupled to the dispensing part opposite to the distributing part in which the groove part is formed and moving in the groove part; One end is fixed to one side of the groove portion and the other end is fixed to the opposite position adjustment block; Plasma processing apparatus comprising a limiting the rotation angle of the inner distribution.

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