KR20060097842A - Plasma apparatus - Google Patents

Abstract

The present invention relates to a plasma apparatus, comprising: a vacuum chamber forming a reaction space; A plate-shaped electrode seated in the vacuum chamber; A pumping port provided around the electrode and generating a plasma flow on top of the electrode; A buffer plate disposed along a side of the electrode and guiding a plasma flow formed on the electrode; And a driving unit for elevating the buffer plate. Thereby, the plasma apparatus which can adjust a plasma flow is provided.

Description

Plasma Apparatus {PLASMA APPARATUS}

1 is a schematic diagram of a plasma apparatus according to a first embodiment of the present invention;

2 is a plan view of a plasma apparatus according to a first embodiment of the present invention;

3 is a cross-sectional view taken along line III-III of FIG. 2;

4A and 4B are perspective views illustrating main parts of a plasma flow control principle;

5 is a schematic diagram of a plasma apparatus according to a second embodiment of the present invention.

Explanation of Signs of Major Parts of Drawings

 1 plasma apparatus 11 vacuum chamber

21: upper electrode 31: lower electrode

41: buffer plate 50: drive unit

51: drive motor 52: drive guide shaft

61: RF power 71: pump

81: pumping port 91: support jaw

100: substrate

The present invention relates to a plasma apparatus, and more particularly, to a plasma apparatus capable of adjusting plasma flow.

In manufacturing a substrate of a semiconductor or liquid crystal display device, an etching process is used to form a desired pattern on the substrate. The etching process is divided into wet etching and dry etching. In dry etching, plasma is usually used.

In dry etching using plasma, a reactive gas is introduced into a vacuum chamber and plasma is discharged under a predetermined pressure. The gas introduced by the plasma discharge is separated into ions, radicals and electrons. At this time, collisions and mutual reactions occur by the applied electric field, and ions react with the substrate by the electric field and radicals by diffusion. Etching is caused by the simultaneous action of physical collisions and chemical reactions. The etching method is divided into a plasma etching method in which radicals mainly participate in etching, and a reactive ion etching in which ions mainly participate in etching.

In the above plasma apparatus, the plasma is formed between the upper electrode and the lower electrode, and the upper electrode and the lower electrode are usually made of aluminum. Here, a plurality of gas passing holes are formed in the upper electrode to introduce the reaction gas. The substrate to be etched is mounted on the upper surface of the lower electrode.

Here, it is necessary to uniformly distribute the plasma formed between the upper electrode and the lower electrode on the substrate for uniform etching. Thus, the buffer plate is disposed along the side edge of the lower electrode, and the plasma is flowed by suction of the pump by forming a pumping port connected to the pump in a predetermined area around the electrode.

However, since the plasma flows toward the pumping port, the plasma density is high in the direction in which the pumping port is formed, and the plasma density is low in the region between the pumping ports, whereby the etching uniformity of the substrate is low.

Accordingly, it is an object of the present invention to provide a plasma apparatus capable of regulating plasma flow.

The object is, according to the present invention, a vacuum chamber for forming a reaction space; A plate-shaped electrode seated in the vacuum chamber; A pumping port provided around the electrode and generating a plasma flow on top of the electrode; A buffer plate disposed along a side of the electrode and guiding a plasma flow formed on the electrode; And a drive unit for elevating the buffer plate.

Here, the electrode may be provided in the shape of a square plate.

In addition, the driving unit independently lifts and lowers each of the buffer plates disposed on each side of the lower electrode, thereby uniformly distributing the plasma flow.

In addition, the pumping port may be disposed in each side of the lower electrode and may be provided in an area between the buffer plates adjacent to each other.

And, it is preferable to further include a pump which is located below the vacuum chamber and connected to the pumping port to maintain the vacuum in the vacuum chamber.

Here, the driving unit may be at least one of an air cylinder and a driving motor.

An object of the present invention, the vacuum chamber for forming a reaction space; A plate-shaped electrode seated inside the vacuum chamber; A plurality of support jaws disposed in an up-down direction on at least one side of the inner side of the vacuum chamber and the side of the electrode; A pumping port provided around the electrode and generating a plasma flow on top of the electrode; And a buffer plate which is supported on the support jaw and is disposed along the side of the electrode and guides the plasma flow formed on the electrode.

Hereinafter, the present invention will be described in detail with reference to the drawings.

1 is a schematic diagram of a plasma apparatus according to a first embodiment of the present invention, FIG. 2 is a plan view of a plasma apparatus according to the first embodiment of the present invention, and FIG. 3 is a cross-sectional view taken along line III-III of FIG.

The plasma apparatus 1 includes a vacuum chamber 11, an upper electrode 21, a lower electrode 31, a buffer plate 41, a driver 50, an RF power supply 61, and a pump 71.

The vacuum chamber 11 forms a reaction space and accommodates an upper electrode 21, a lower electrode 31, a buffer plate 41, and the like, which will be described later. The vacuum chamber 11 is formed with an inlet through which the reaction gas flows, and a hole connected to the pump 71 to maintain a vacuum in the vacuum chamber 11.

The upper electrode 21 has a plate shape and is usually made of aluminum. In addition, a plurality of gas passing holes are formed in the upper electrode 21 to introduce the reaction gas. The upper electrode 21 is formed with an aluminum oxide layer and / or an aluminum hydrate layer to stabilize or insulate the upper electrode 21.

The lower electrode 31 is also generally plate-like like the upper electrode 21 and is made of aluminum. The substrate 100 to be etched is mounted on the upper surface of the lower electrode 31. The lower electrode 31 may be manufactured in a square plate shape. In addition, the lower electrode 31 may be manufactured in a plate shape having a step formed thereon, and protrusions may be formed on the upper surface of the lower electrode 31 to solve a problem in which staining occurs on the substrate 100 due to temperature and static electricity. It may be. The lower electrode 31 may further include a ceramic coating layer by ceramic spraying or anodizing to insulate the lower electrode 31.

The buffer plate 41 has a rectangular plate shape and is disposed along the side edge of the lower electrode 31. That is, the long horizontal side of the buffer plate 41 is made of a length corresponding to the side of the lower electrode 31, the vertical side is provided with a length corresponding to the width between the lower electrode 31 and the vacuum chamber 11 is vacuum It is adjacent to the inner side of the chamber 11. As shown in FIG. 2, a hole called a pumping port 81 is formed in an area between each buffer plate 41, that is, at an edge of the lower electrode 31 by a gap between adjacent buffer plates 41. have. In addition, the lower side of the buffer plate 41 is coupled to the drive guide shaft 52 of the drive unit 50, and is moved up and down by the drive unit 50. Each buffer plate 41 is separated and can be independently lifted. The buffer plate 41 guides the plasma flow formed on the lower electrode 31 to uniformly distribute the plasma flow.

The driving unit 50 includes a driving motor 51 and a driving guide shaft 52. The driving guide shaft 52 contacts the lower surface of the buffer plate 41 to raise and lower the buffer plate 41. The driving unit 50 may include an air cylinder, and the plurality of buffer plates 41 may be moved up and down by one driving unit 50, and the driving unit 50 corresponding to each buffer plate 41 may be provided. There may be. By the driving unit 50, each buffer plate 41 can be moved up and down independently, it may be moved up and down together.

The RF power supply 61 applies power to the upper electrode 21 and the lower electrode 31 so that a plasma is generated between the upper electrode 21 and the lower electrode 31. When power is applied, electrons are emitted from one electrode. The energy of the emitted electrons is greater than the ionization energy of the reaction gas in the vacuum chamber 11, so that the particles of the reaction gas are ionized by electron mobilization, so that the ion particles of the (+) potential and the electrons of the (-) potential are not ionized. A plasma composed of neutral state particles is generated. As described above, the ion particles are etched while colliding with the substrate 100 by the potential difference induced by the RF power source 61 to the electrodes 21 and 31.

The pump 71 is located at the lower side of the vacuum chamber 11 and is connected to the pumping port 81. The pump 71 functions to maintain a vacuum in the vacuum chamber 11, and is connected to the pumping port 81 to flow a plasma flow formed on the lower electrode 31. Here, the pump 71 includes at least one.

4A and 4B, the control principle of the plasma flow according to the present invention is as follows.

The upper electrode 21 and the lower electrode 31 are spaced apart from each other in the vacuum chamber 11, and the substrate 100, which is an object to be etched, is positioned therebetween. The metal layer, the semiconductor layer, and the insulating layer to be etched are exposed on the substrate 100. Although not shown, a receptor for supporting the substrate 100 may also be formed in the vacuum chamber 11.

When the reaction gas flows into the upper electrode 21 and the power is supplied from the RF power source 61, a plasma is generated between the upper electrode 21 and the lower electrode 31. Argon is usually used as the reaction gas.

Then, the plasma formed by the pumping port 81 connected to the pump 71 is flowed. That is, the plasma formed in the upper space flows toward the pumping port 81 by the suction force of the pump 71. Here, as shown in FIG. 4A, when the buffer plate 41 is positioned on the same surface as the upper surface of the lower electrode 31, no plasma flow is generated or weak on the upper portion of the buffer plate 41, and thus the pumping port ( The plasma density is high in the direction in which the 81 is formed, and the plasma density is low in the region between the pumping ports 81, whereby the etching uniformity of the substrate is low.

However, as shown in FIG. 4B, when the buffer plate 41 is positioned lower than the upper surface of the lower electrode 31, the pumping port 81 is also formed lower than the upper surface of the lower electrode 31, so that the buffer plate 41 is lower. Plasma flow is generated along the longitudinal direction of the buffer plate 41 at the top. Therefore, the plasma density is relatively low on the side where the pumping port 81 is formed, and the plasma density is relatively high in the region between the pumping ports 81, whereby the plasma is uniformly distributed on the upper portion of the substrate 100. .

In addition, it is possible to control the density of the plasma distribution by individually adjusting the lifting position of each buffer plate 41, it is possible to adjust the etching map (ETCH MAP) and the etching rate (ETCH RATE) according to the etching target. In addition, the etching uniformity is improved by controlling the plasma flow to obtain an etching accuracy and a smooth and precise etching slope (ETCH PROFILE).

After the etching process, the process gas in the vacuum chamber 11 is discharged to the outside of the vacuum chamber 11 by the vacuum device.

5 is a schematic diagram of a plasma apparatus of a second embodiment according to the present invention.

The configuration in the second embodiment is almost the same as that in the above-described first embodiment, but the configuration for lifting and lowering the buffer plate 41 is different.

In the case of the first embodiment, the driving unit 50 having the driving motor or the cylinder must be separately provided, thereby increasing the manufacturing cost of the plasma apparatus 1. Therefore, as shown in FIG. 5, a plurality of support jaws 91 are disposed on the inner side of the vacuum chamber 11 and at least one side of the side surface of the lower electrode 31 in the vertical direction. The buffer plate 41 is supported by the support jaw 91 to adjust the lifting position.

Here, the plurality of support jaw 91 is preferably provided at a predetermined position that can achieve the uniformity of the plasma distribution. Simple, low-cost plasma flow control by adjusting the lift position on the buffer plate 41 to match the substrate 100 characteristics to be etched to achieve the desired ETCH MAP and etch rate. To achieve a predetermined etching uniformity.

In addition, the lifting position of each buffer plate 41 can also be adjusted individually.

Here, the plasma apparatus in the present invention is not limited to the etching apparatus, and may be used in various ways such as PECVD, CVD deposition, ASHING for removing the photosensitive film PR, vacuum chamber cleaning, and the like.

As described above, according to the present invention, it is possible to provide a plasma apparatus with improved etching uniformity by adjusting plasma flow.

Claims (7)

A vacuum chamber forming a reaction space; A plate-shaped electrode seated in the vacuum chamber; A pumping port provided around the electrode and generating a plasma flow on the electrode; A buffer plate disposed along a side of the electrode and guiding a plasma flow formed on the electrode; And And a driving unit for elevating the buffer plate. The method of claim 1, And said electrode is provided in a rectangular plate shape. The method of claim 1, And the driving unit independently lifts and lowers each of the buffer plates arranged on each side of the lower electrode. The method of claim 1, The pumping port is disposed in each side of the lower electrode, the plasma apparatus, characterized in that formed in the region between the adjacent buffer plate. The method of claim 1, And a pump positioned under the vacuum chamber and connected to the pumping port to maintain a vacuum in the vacuum chamber. The method of claim 1, The driving unit includes at least one of an air cylinder and a driving motor. A vacuum chamber forming a reaction space; A plate-shaped electrode seated inside the vacuum chamber; A plurality of support jaws disposed in an up-down direction on at least one side of an inner surface of the vacuum chamber and a side surface of the electrode; A pumping port provided around the electrode and generating a plasma flow on the electrode; And And a buffer plate which is supported by the support jaw and is disposed along the side of the electrode and guides the plasma flow formed on the electrode.

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