KR20070118482A - Plasma processing apparatus and method for treating semiconductor substrates using the same - Google Patents

Abstract

A plasma processing apparatus and a method for treating a semiconductor substrate using the same are provided to enhance efficiency thereof by performing simultaneously a byproduct discharging process and a plasma leakage preventing process. A process chamber is formed to perform a plasma treatment process. An upper electrode(200) is formed at an upper part within the process chamber. A lower electrode(100) is installed opposite to the upper electrode within the process chamber. A plurality of exhaust members(320,340) are arranged around the lower electrode and includes a path for discharging byproducts within the process chamber. The exhaust members are arranged opposite to each other. Shapes or arrangements of paths formed at the adjacent exhaust members are different from each other. At least one of the exhaust members is ring shape typed a plate member and has a plurality of through holes.

Description

Plasma processing apparatus and substrate processing method using the same {PLASMA PROCESSING APPARATUS AND METHOD FOR TREATING SEMICONDUCTOR SUBSTRATES USING THE SAME}

1 is a perspective view showing an example of a typical baffle plate,

2A and 2B are an enlarged perspective view and a plan view of a portion A of FIG. 1, respectively;

3 is a schematic configuration diagram showing an example of a plasma processing apparatus according to the present invention;

FIG. 4 is a schematic perspective view of the first exhaust member shown in FIG. 3;

5 is a schematic cross-sectional view taken along the line BB ′ of FIG. 4;

FIG. 6 is a schematic perspective view of the second exhaust member shown in FIG. 3;

FIG. 7A is a schematic cross-sectional view taken along the line CC ′ of FIG. 6;

FIG. 7B is a schematic cross-sectional view taken along the line D-D 'of FIG. 6.

<Description of Symbols for Main Parts of Drawings>

10 process chamber 20 plasma processing space

30: exhaust space 100: lower electrode

200: upper electrode 320: first exhaust member

326: through-hole 340: second exhaust member

346: slot 347: slope

The present invention relates to a semiconductor manufacturing apparatus and method, and more particularly, to a plasma processing apparatus for processing a substrate using a plasma and a substrate processing method using the same.

In general, plasma refers to an ionized gas state composed of ions, electrons, radicals, and the like, and plasma is generated by a very high temperature, a strong electric field, or high frequency electromagnetic fields (RF Electromagnetic Fields).

Particularly, plasma generation by glow discharge is performed by free electrons excited by direct current or high frequency electromagnetic field, and the excited free electrons collide with gas molecules to generate active species such as ions, radicals and electrons. ) In addition, such active species physically or chemically act on the surface of the material to change the surface properties. This change in the surface properties of the material by the active species is called plasma surface treatment.

The plasma processing apparatus refers to a device for depositing a reaction material into a plasma state and depositing the same on a semiconductor substrate, or cleaning, ashing, or etching a substrate using the reaction material in a plasma state.

A plasma processing apparatus, such as a parallel plate type plasma processing apparatus, includes a lower electrode provided in a vacuum chamber to mount a semiconductor substrate and the like, and an upper electrode provided above the vacuum chamber so as to face the lower electrode. And a bottom electrode to form a pair of parallel plate electrodes. A baffle plate is provided between the plasma generation space between the upper and lower electrodes and the lower space of the lower electrode to prevent the leakage of plasma and to discharge the exhaust gas and the reaction by-products generated during the plasma treatment process.

1 is a schematic perspective view illustrating an example of a general baffle plate, and FIGS. 2A and 2B are respectively a schematic perspective view and a plan view showing an enlarged portion A of FIG. 1.

1 to 2B, the baffle plate 1 is provided with a ring-shaped circular plate member 4 having an opening 2 formed at its center, and the slot member 4 has a plurality of slots 6. Is formed. The slots 6 extend radially from the inner circumference of the plate member 4 toward the outer circumference, the width T _{S of} which is uniformly formed with a width (approximately 1 mm) which can prevent the leakage of the plasma.

Thus, as shown in FIG. 2B, the spacing T ₁ between the slots 6 near the outer circumference of the baffle plate 1 is larger than the spacing T ₂ between the slots 6 near the inner circumference. For this reason, compared with the inner peripheral part of the baffle plate 1, exhaust gas, reaction by-products, etc. cannot be discharge | released relatively smoothly in the outer peripheral part, and there existed a problem that the efficiency of a plasma processing process fell.

Therefore, the present invention was created to solve the problems in view of the conventional conventional plasma processing apparatus as described above, the object of the present invention is to prevent the leakage of plasma, and at the same time to quickly exhaust gas or reaction by-products The present invention provides a plasma processing apparatus and a substrate processing method using the same.

In order to achieve the above object, a plasma processing apparatus according to the present invention includes a process chamber in which a plasma processing process is performed; An upper electrode provided above the process chamber; A lower electrode disposed below the upper electrode to face the upper electrode; A plurality of exhaust members disposed around the lower electrode and providing a passage through which the reaction by-products in the process chamber are discharged, wherein the exhaust members are disposed to face each other in an up and down direction.

In the plasma processing apparatus according to the present invention having the configuration as described above, at least one of the shape or arrangement of the passages formed in the exhaust members adjacent to each other is preferably provided different from each other.

According to one feature of the invention, at least one of the exhaust member is provided with a ring-shaped plate member having a hole in the center, it is preferable that a plurality of through-holes are formed in the plate member.

According to another feature of the invention, at least one of the exhaust member is provided with a ring-shaped plate member having a hole in the center, it is preferable that a plurality of slots of the long hole shape is formed in the plate member.

In addition, the plurality of slots may extend radially from the inner circumference of the plate member toward the outer circumference thereof, and the inner side of the plurality of slots may be inclined so that the flow area of the upper end of the passage through which the reaction byproduct is discharged is enlarged.

According to an aspect of the invention, the plurality of exhaust members are disposed on the upper periphery of the lower electrode, the first exhaust member formed with a plurality of holes in the ring-shaped plate member formed in the center hole; And a second exhaust member disposed below the first exhaust member and having a plurality of slots having a long hole shape in a ring-shaped plate member having a hole formed in a central portion thereof.

In order to achieve the above object, the substrate processing method using the plasma processing apparatus according to the present invention comprises the steps of: providing a processing gas to a process chamber in which a plasma processing process is performed; Supplying power to one of the upper and lower electrodes provided inside the process chamber to form an electric field in a plasma processing space between the upper electrode and the lower electrode; Generating a plasma from the process gas by the electric field; Discharging the byproduct of the plasma processing process through the through holes of the first baffle plate disposed above the circumference of the lower electrode; And discharging the by-product discharged through the first baffle plate through slots of the second baffle plate spaced downward from the first baffle plate.

Hereinafter, a plasma processing apparatus and a substrate processing method using the same according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. First, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are assigned to the same components as much as possible, even if shown on different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

(Example)

3 is a schematic configuration diagram showing an example of a plasma processing apparatus according to the present invention.

Referring to FIG. 3, a pair of parallel plate electrodes are provided inside the process chamber 10 in which the plasma processing process is performed. The electrode has a lower electrode 100 installed at the lower end of the process chamber 10 and an upper electrode 200 provided at the upper end of the process chamber 10 so as to face the lower electrode 100.

High frequency power supplies 110a and 110b are connected to the lower electrode 100 through matchers 112a and 112b, and an electrostatic chuck 120 for supporting a semiconductor substrate is provided on the upper surface of the lower electrode 100. The electrostatic chuck 120 has a configuration in which the electrode 124 for the electrostatic chuck is disposed in the insulating layer 122, and a DC power supply 126 is connected to the electrode for the electrostatic chuck 124. Around the lower electrode 100, a plurality of exhaust members 300 are provided in a vertical direction to provide a passage through which reaction by-products in the process chamber 10 are discharged.

The upper electrode 200 is grounded, and a gas filling space 210 filled with a processing gas supplied from the outside is formed therein. The lower surface of the upper electrode 200, that is, the plasma exposure surface 220 may be coated with ceramic, and the plasma exposure surface 220 may have a processing gas filled in the gas filling space 210 toward the substrate W. A plurality of injection holes 230 are formed to be injected. In addition, a cooling member 400 for cooling the upper electrode 200 is provided on the upper surface of the upper electrode 200, that is, the surface opposite to the plasma exposure surface.

The magnetic field forming mechanism 500 is disposed around the process chamber 10 so that a magnetic field is formed in the plasma processing space 20 in the process chamber 10, and the magnetic field forming mechanism is rotated so that the magnetic field formed in the process chamber 10 is rotated. The rotary mechanism 510 is connected to 500.

In addition, an exhaust port 610 is formed at the lower end of the process chamber 10 so that the reaction by-product passing through the exhaust member 300 is discharged to the outside of the process chamber 10, and the reaction by-product is pumped in the exhaust port 610. Thus, the exhaust unit 600 for maintaining the inside of the process chamber 10 in a constant vacuum state is connected.

The exhaust members 300 divide the inside of the process chamber 10 into a plasma processing space 20 between the lower electrode 100 and the upper electrode 200 and an exhaust space 30 below the lower electrode 100. . Reaction by-products or exhaust gases generated during the process are discharged from the plasma processing space 20 to the exhaust space 30 through the exhaust member 300, and the leakage of plasma through the exhaust member 300 should be minimized. To this end, in the present invention, a plurality of exhaust members 300 are disposed around the lower electrode 100 to provide a discharge passage of the reaction byproduct. The plurality of exhaust members 300 are disposed to face each other in the vertical direction around the lower electrode 100. For example, the first exhaust member 320 may be disposed above the circumference of the lower electrode 100, and the second exhaust member 340 may be disposed at a position spaced downward from the first exhaust member 320. . In addition, the passages of the reaction by-products formed in the first exhaust member 320 and the second exhaust member 340 may have different shapes or arrangements.

4 is a schematic perspective view of the first exhaust member illustrated in FIG. 3, and FIG. 5 is a schematic cross-sectional view taken along line BB ′ of FIG. 4.

4 and 5, the first exhaust member 320 may be provided as a ring-shaped circular plate member 324 in which a hole 322 is formed at a central portion thereof. The plate member 324 is formed with a plurality of through holes 326. The through holes 326 may have a circular cross section and may be formed to have a diameter of a predetermined size to minimize leakage of plasma. In addition, the through holes 326 may be disposed at uniform intervals. As such, since the through holes 326 having a predetermined diameter are formed at uniform intervals in the first exhaust member 320, the first exhaust member 320 uniformly reacts reaction by-products in the plasma processing space 20. Discharge, and at the same time it can minimize the leakage of plasma.

FIG. 6 is a schematic perspective view of the second exhaust member illustrated in FIG. 3, FIG. 7A is a schematic cross-sectional view taken along the line CC ′ of FIG. 6, and FIG. 7B is a schematic cross-sectional view taken along the line D-D ′ of FIG. 6. .

)은 판 부재(344)의 평면을 기준으로 30°내지 60°범위의 각을 이루는 것이 바람직하며, 이 밖에도 다양한 경사각을 가지는 경사면을 형성할 수도 있다. 이와 같이, 슬롯들(346)의 상단 유동 면적을 하단 유동 면적보다 넓게 함으로써, 제 1 배기 부재(320)를 통해 배출된 반응 부산물이 제 2 배기 부재(340)를 통해 배기 공간(30)으로 신속하게 배출된다. 6 to 7B, the second exhaust member 340 is provided as a ring-shaped circular plate member 344 having a hole 342 formed at the center thereof. The plate member 344 is formed with a plurality of slots 346 having a long hole shape. Here, the long hole refers to a hole formed to have a relatively long length by comparing the width and the full length. Slots 346 extend radially from the inner circumference of the plate member 344 toward the outer circumference, and the width T _S is formed to a width capable of preventing the leakage of plasma. In addition, the slots 346 may have an inclined surface 347 on an inner side thereof so that the flow area of the upper end of the passage through which the reaction by-product is discharged is enlarged. As shown in FIGS. 7A and 7B, only a portion of the upper end of the inner surface may be formed as the inclined surface 347, and the entire inner surface may also be inclined. Here, the inclination angle of the inclined surface 347 (

) May form an angle in the range of 30 ° to 60 ° based on the plane of the plate member 344, and may also form an inclined surface having various inclination angles. As such, by making the upper flow area of the slots 346 wider than the lower flow area, the reaction by-product discharged through the first exhaust member 320 is rapidly passed through the second exhaust member 340 to the exhaust space 30. Is discharged.

Referring to the operation of the plasma processing apparatus according to the present invention having the configuration as described above are as follows.

The plasma processing apparatus mounts the semiconductor substrate W on the electrostatic chuck 120, applies a predetermined DC voltage to the electrode 124 for the electrostatic chuck, and sucks and holds the semiconductor substrate W. The processing gas is supplied to the plasma processing space 20 between the upper electrode 200 and the lower electrode 100 through the injection hole 230 of the 200. At the same time, a high frequency electric power of a predetermined frequency is supplied to the lower electrode 100 to form a high frequency electric field in the plasma processing space 20. In addition, a predetermined magnetic field is formed in the processing space 20 by the magnetic field forming mechanism 500, and the magnetic field is rotated by the rotating mechanism 510 connected to the magnetic field forming mechanism 500. As a result, a predetermined plasma is generated from the processing gas supplied to the plasma processing space 20, and the generated plasma is applied to the semiconductor substrate W to perform a substrate processing process such as cleaning, ashing, or etching. During the substrate processing process, reaction by-products are generated in the plasma processing space 20, and the reaction by-products are first discharged through the through holes 326 of the first exhaust member 320. Then, the reaction by-product discharged through the first exhaust member 320 is discharged to the exhaust space 30 below the lower electrode 100 through the slots 346 of the second exhaust member 340, the exhaust port It is discharged to the outside of the process chamber 10 through 610. At this time, the first exhaust member 320 and the second exhaust member 340 discharge the reaction by-products in the plasma processing space 20 uniformly and quickly, and the plasma generated in the plasma processing space 20 is discharged to the exhaust space ( 30) to minimize leakage.

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention pertains may make various modifications and changes without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

As described above, according to the present invention, it is possible to minimize the leakage of plasma in the process chamber and to discharge the exhaust gas and the reaction by-products quickly and uniformly.

Claims (8)

A process chamber in which the plasma processing process is performed; An upper electrode provided above the process chamber; A lower electrode disposed below the upper electrode to face the upper electrode; And a plurality of exhaust members disposed around the lower electrode and providing a passage through which reaction by-products in the process chamber are discharged. And the exhaust members are disposed to face each other in the vertical direction. The method of claim 1, At least one of the shape or arrangement of the passages formed in the exhaust members adjacent to each other is provided differently from each other. The method of claim 2, At least one of the exhaust members, And a ring-shaped plate member having a hole formed in a central portion thereof, wherein the plate member is provided with a plurality of through holes. The method of claim 2 or 3, At least one of the exhaust members, And a ring-shaped plate member having a hole formed in a central portion thereof, wherein the plate member is formed with a plurality of slots having a long hole shape. The method of claim 4, wherein The plurality of slots, And a radial extension extending from the inner circumference of the plate member toward the outer circumference. The method of claim 4, wherein The plurality of slots, Plasma processing apparatus characterized in that the inner surface is inclined so that the flow area of the upper end of the passage through which the reaction by-products are discharged. The method of claim 1, The plurality of exhaust members, A first exhaust member disposed on an upper circumference of the lower electrode and having a plurality of through holes formed in a ring-shaped plate member having a hole formed in a central portion thereof; And a second exhaust member disposed below the first exhaust member and having a plurality of slots having a long hole shape in a ring-shaped plate member having a hole formed in a center thereof. In the method of processing a substrate using a plasma, Providing a process gas to a process chamber in which the plasma processing process is performed; Supplying power to one of the upper and lower electrodes provided inside the process chamber to form an electric field in a plasma processing space between the upper electrode and the lower electrode; Generating a plasma from the process gas by the electric field; Discharging the reaction by-products of the plasma processing process through the openings of the first exhaust member disposed above the circumference of the lower electrode; And discharging the by-product discharged through the first exhaust member through slots of the second exhaust member spaced downward from the first exhaust member.

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