KR20110066686A - Plasma reactor to generate large area plasma - Google Patents

Abstract

The present invention relates to a plasma reactor for generating a large area plasma. The plasma reactor for generating a large-area plasma of the present invention includes a reactor body having a substrate support for supporting a substrate to be processed therein; A gas supply unit provided at an upper portion of the reactor body and configured to supply a process gas into the reactor body; A circular intermediate electrode provided to divide a space between the substrate support and the gas supply unit; And a discharge is generated between the grounded gas supply unit and the intermediate electrode including a power supply source for applying frequency power to the intermediate electrode. According to the plasma reactor for generating a large-area plasma of the present invention, a discharge is generated between the intermediate electrode and the gas supply unit to generate plasma. In addition, the intermediate electrode may be formed in an easy form for wafer processing and the size of the intermediate electrode may be adjusted according to the size of the wafer. In addition, the substrate to be processed can be treated more uniformly by using a plasma having a large uniform area.

Plasma reactor, large area plasma, electrode

Description

Plasma reactor for generating large size plasma

The present invention relates to a plasma reactor for generating a large-area plasma, and more particularly, to generate a large-area plasma that can generate a large-area plasma more uniformly, thereby improving processing efficiency for a large-area target object. It relates to a plasma reactor.

Plasma is a highly ionized gas containing the same number of positive ions and electrons. Plasma discharges are used for gas excitation to generate active gases containing ions, free radicals, atoms, molecules. Active gases are widely used in various fields and are used in various semiconductor manufacturing processes for manufacturing devices such as integrated circuit devices, liquid crystal displays, solar cells, etc., for example, etching, deposition, cleaning, and ashing. It is variously used for ashing.

There are a number of plasma sources for generating plasma, and the representative examples are capacitive coupled plasma and inductive coupled plasma using radio frequency. Capacitively coupled plasma sources have the advantage of high process productivity compared to other plasma sources due to their high capacity for precise capacitive coupling and ion control. However, when the capacitively coupled electrode is enlarged in order to process an enlarged substrate, the electrode may be deformed or damaged by deterioration of the electrode. In this case, the electric field strength may be uneven, which may result in uneven plasma density and contaminate the inside of the reactor. In the case of an inductively coupled plasma source, it is also difficult to obtain a uniform plasma density when the area of the induction coil antenna is increased.

In recent years, the semiconductor manufacturing industry has been further improved due to various factors such as ultra miniaturization of semiconductor devices, the enlargement of silicon wafer substrates or substrates to be processed such as glass or plastic substrates for manufacturing semiconductor circuits, and the development of new materials to be processed. Plasma treatment technology is required. In particular, there is a need for improved plasma sources and plasma processing techniques that have good processing capabilities for large area substrates. Furthermore, various semiconductor manufacturing apparatuses using lasers have been provided. Semiconductor manufacturing processes using lasers have been widely applied to various processes such as deposition, etching, annealing, cleaning, and the like on a substrate to be processed. In the case of a semiconductor manufacturing process using such a laser, the above-described problems exist.

The enlargement of the substrate to be processed causes the enlargement of the entire production equipment. Larger production facilities increase the overall plant area, resulting in increased production costs. Therefore, there is a need for a plasma reactor and a plasma processing system capable of minimizing the installation area. In particular, in the semiconductor manufacturing process, unit productivity is one of the important factors affecting the price of the final product.

An object of the present invention is to provide a plasma reactor for generating a large-area plasma capable of uniformly generating and maintaining a large-area plasma by installing an intermediate electrode in the middle of the plasma reactor.

Another object of the present invention is to provide a plasma reactor that generates a large-area plasma by varying the size of the intermediate electrode according to the size of the substrate to be processed.

One aspect of the present invention for achieving the above technical problem relates to a plasma reactor for generating a large-area plasma. The plasma reactor for generating a large-area plasma of the present invention includes a reactor body having a substrate support for supporting a substrate to be processed therein; A gas supply unit provided at an upper portion of the reactor body and configured to supply a process gas into the reactor body; A circular intermediate electrode provided to divide a space between the substrate support and the gas supply unit; And a discharge is generated between the grounded gas supply unit and the intermediate electrode including a power supply source for applying frequency power to the intermediate electrode.

In an embodiment, the intermediate electrode may include at least one power input terminal for inputting frequency power supplied from the power supply source; And a plurality of through holes for passing the generated plasma.

In one embodiment, the circular intermediate electrode is formed by combining a plurality of fan-shaped intermediate electrode member.

In one embodiment, the circular intermediate electrode further includes a frame for mounting the plurality of intermediate electrode members.

In one embodiment, the plasma reactor includes at least one current balancing circuit for automatically adjusting the mutual balance of the current supplied to the plurality of intermediate electrode members included in the intermediate electrode.

In one embodiment, the current balancing circuit includes a feed line separated into at least two, the intermediate electrode member is connected to the end of the feed line to automatically adjust the mutual balance of current between adjacent feed lines.

Another large-area plasma reactor for generating a plasma of the present invention includes a reactor body having a substrate support therein for supporting a substrate to be processed; A gas supply unit provided at an upper portion of the reactor body and configured to supply a process gas into the reactor body; A capacitively coupled electrode assembly provided below the gas supply part and having a plurality of capacitively coupled electrodes; A circular intermediate electrode provided to divide a space between the substrate support and the gas supply unit; And a power supply source for applying frequency power to the capacitively coupled electrode assembly, wherein a discharge occurs between the grounded intermediate electrode and the capacitively coupled electrode assembly.

According to the plasma reactor for generating a large-area plasma of the present invention, a discharge is generated between the intermediate electrode and the gas supply unit to generate plasma. In addition, the intermediate electrode may be formed in an easy form for wafer processing and the size of the intermediate electrode may be adjusted according to the size of the wafer. In addition, the substrate to be processed can be treated more uniformly by using a plasma having a large uniform area.

In order to fully understand the present invention, preferred embodiments of the present invention will be described with reference to the accompanying drawings. Embodiment of the present invention may be modified in various forms, the scope of the invention should not be construed as limited to the embodiments described in detail below. This embodiment is provided to more completely explain the present invention to those skilled in the art. Therefore, the shape of the elements in the drawings and the like may be exaggerated to emphasize a more clear description. It should be noted that the same members in each drawing are sometimes shown with the same reference numerals. Detailed descriptions of well-known functions and constructions which may be unnecessarily obscured by the gist of the present invention are omitted.

1 is an exploded perspective view of a plasma reactor having a rectangular intermediate electrode plate and a gas supply unit grounded according to a first preferred embodiment of the present invention, and FIG. 2 is a cross-sectional view of the plasma reactor shown in FIG. One drawing.

As shown in FIGS. 1 and 2, the plasma reactor 10 includes a reactor body 11, a gas supply unit 20, and an intermediate electrode 30. The inside of the reactor body 11 is provided with a substrate support 12 on which the substrate 13 to be processed is placed. The gas supply unit 20 is provided at the top of the reactor body 11. The gas supply unit 20 includes one gas inlet 21 and a plurality of gas injection holes 23. Process gas provided from a gas source (not shown) is provided to the gas inlet 21 of the gas supply 20 and is supplied into the reactor body 11 through the gas injection port 23. The intermediate electrode 30 is installed inside the reactor body 11 so that the space between the gas supply unit 20 and the substrate support 12 is divided.

The plasma reactor 10 includes a reactor support 11 and a substrate support 12 on which a substrate 13 to be processed is placed. The reactor body 11 is connected to a vacuum pump 8. The reactor body 11 may be made of a metal material such as aluminum, stainless steel, or copper. Or it may be made of coated metal, for example anodized aluminum or nickel plated aluminum. Alternatively, a composite metal in which carbon nanotubes are covalently bonded may be used. Alternatively, it may be made of refractory metal. As another alternative, it is also possible to fabricate the reactor body 11 in whole or in part with an electrically insulating material such as quartz, ceramic. As such, the reactor body 11 may be made of any material suitable for carrying out the intended plasma process. The structure of the reactor body 11 may have a structure suitable for uniform generation of the plasma, for example, a circular structure or a square structure, or any other structure depending on the substrate 13 to be processed. The substrate 13 to be processed is, for example, substrates such as wafer substrates, glass substrates, plastic substrates, etc. for the manufacture of various devices such as semiconductor devices, display devices, solar cells, and the like.

The substrate support 12 for supporting the substrate 13 to be processed is provided in the plasma reactor 10. The substrate support 12 is connected and biased to a bias power source 46 (two bias power sources that supply different radio frequency power sources may be connected). A bias power supply 46 is electrically connected to the substrate support 12 through a common impedance matcher 48 (or each impedance matcher). The dual bias structure of the substrate support 12 facilitates plasma generation inside the plasma reactor 10 and further improves plasma ion energy control to improve process productivity. Alternatively, the substrate support 12 may be modified to have a zero potential without supplying bias power. The substrate support 12 may include an electrostatic chuck. Alternatively, the substrate support 12 may include a heater. Basically, the substrate support 12 is composed of a structure that can be lifted or lowered vertically. Alternatively, the substrate support 12 has a structure capable of linearly or rotationally moving in parallel with the capacitively coupled electrode assembly 30. In such a movable structure, a drive mechanism for linearly or rotationally moving the substrate support 12 may be included. An exhaust baffle (not shown) may be configured at the lower portion of the reactor body 11 for uniform exhaust of the gas.

An intermediate electrode 30 is provided between the gas supply unit 20 and the substrate support 12. The intermediate electrode 30 is installed to divide the space between the gas supply unit 20 and the substrate support 12. At this time, the gas supply unit 20 is connected to the ground, the intermediate electrode 30 is connected to the power supply source 40 is supplied with a radio frequency power. Here, the plasma reactor 10 may be provided with two or more power sources for selectively supplying different frequencies. The frequency power generated from the power source 40 is provided to the intermediate electrode 30 through the impedance matcher 43. The discharge is generated between the grounded gas supply unit 20 and the intermediate electrode 30 to which the radio frequency power is supplied to generate plasma. The intermediate electrode 30 may be formed of one intermediate electrode plate or may include a plurality of intermediate electrode members. This intermediate electrode plate is formed in a circular shape which is easy for wafer processing.

2 to 4 are plan views illustrating intermediate electrode plates having through holes having various shapes according to the present invention.

As illustrated in FIGS. 2 to 4, the circular intermediate electrode plate 32 includes one power input terminal 32a and a plurality of through holes 32b. The power input terminal 32a is provided at one or more intermediate electrode plates 32 to be connected to the power supply source 40. The plurality of through holes 32b are provided in the intermediate electrode plate 32. The plasma generated between the gas supply unit 20 and the intermediate electrode plate 32 is supplied to the substrate 13 through the through hole 32b provided in the intermediate electrode plate 32. The through hole 32b may be formed in various shapes, such as a rectangle and a circle, as shown in the drawing.

In addition, the antenna coil (not shown) may be wound around the edge of the intermediate electrode plate 32 to improve plasma efficiency of the peripheral area of the substrate 13. In addition, a magnetic core (not shown) may be further installed on the antenna coil (not shown) to improve plasma efficiency.

5 is a diagram illustrating an intermediate electrode plate having a plurality of fan-shaped intermediate electrode members, and FIG. 6 is an exploded perspective view illustrating a state in which the intermediate electrode members of the intermediate electrode plate illustrated in FIG. 5 are separated.

As shown in FIGS. 5 and 6, the intermediate electrode plate 32 is formed with a plurality of fan-shaped intermediate electrode members 34. The intermediate electrode plate 32 may be formed by combining intermediate electrode members formed in various forms. The intermediate electrode 32 according to an embodiment of the present invention may arrange a plurality of fan-shaped intermediate electrode members 34. Thus, the overall shape of the intermediate electrode plate 32 is circular. The intermediate electrode member 34 includes at least one power input terminal 34a and a plurality of through holes 34b in the same manner as the intermediate electrode plate 32. In addition, the intermediate electrode plate 32 is provided with a frame 36 on which the intermediate electrode member 34 can be mounted while being insulated between the respective intermediate electrode members 34. Frame 36 has a mounting space corresponding to the shape and the number of the installation of the intermediate electrode member 34, it is possible to install a plurality of intermediate electrode member 34 in each mounting space. Therefore, the plurality of intermediate electrode members 34 can be arranged and used to form a large-area plasma. In addition, according to the size of the substrate 13 to be processed can be used to arrange the intermediate electrode member 34 as necessary. In addition, the antenna coil (not shown) may be wound around the edge of the intermediate electrode plate 32 to improve plasma efficiency of the peripheral area of the substrate 13. In addition, a magnetic core (not shown) may be further installed on the antenna coil (not shown) to improve plasma efficiency.

7 is a cross-sectional view showing a state in which the intermediate electrode plate is mounted on the reactor body.

As shown in Figure 7, the reactor body 11 is provided with a locking step (11a) therein so that the intermediate electrode plate 32 can be installed. That is, a part of the intermediate electrode plate 32 is installed while being caught on the locking step 11a provided on the inner wall of the reactor body 11. The locking step 11a may be provided along the inner wall of the reactor body 11 or may be installed only on a portion of the inner wall. In addition, although not shown in the drawing, the intermediate electrode plate 32 provided with the frame 36 may be installed on the reactor body 11 with the frame 36 across the engaging jaw 11a.

8 is a view using a power input terminal of the intermediate electrode plate to mount the intermediate electrode assembly to the reactor body.

As shown in FIG. 8, the intermediate electrode plate 32 may be installed in the reactor body 11 using the power input terminal 32a. The power input terminal 32a of the intermediate electrode plate 32 is connected to the power supply source 40 by a power supply line. That is, by extending the length of the power input terminal 32a provided in the intermediate electrode plate 32 to the power distribution unit (not shown) positioned above the gas supply unit 20, the intermediate electrode assembly 34 has the reactor body 11. It can be fixed inside. In addition, the plurality of intermediate electrode members 34 may extend and fix the length of the power input terminal 34a.

FIG. 9 is a plan view illustrating an intermediate electrode plate formed such that the size of the through hole becomes smaller from the outside to the inside, and FIG. 10 is a plan view illustrating the intermediate electrode plate formed so that the size of the through hole increases from the outside to the inside.

9 and 10, the size of the through hole 32b of the intermediate electrode plate 32 may be different from each other. The through holes 32b may be different in size or may be formed in a random size. In one embodiment of the present invention, for example, the size of the through hole 32b may be formed to become smaller from the outside of the intermediate electrode plate 32 toward the inside, and from the outside of the intermediate electrode plate 32 to the inside. It may be formed to grow larger and larger. As such, the size of the through hole 32b may be differently adjusted to adjust the amount of plasma passing through the through hole 32b, thereby controlling the processing efficiency of the central region and the peripheral region of the substrate 13. Similarly, the size of the through hole 34b of the intermediate electrode member 34 may also be variously formed.

11 is a cross-sectional view illustrating a case in which the top and bottom sizes of the through holes are the same or different.

As shown in FIG. 11, for example, when the through hole 32b is circular, the length of the upper diameter r1 and the lower diameter r2 of the through hole 32b may be the same or different. By forming the upper diameter r1 and the lower diameter r2 of the through hole 32b the same or different, it is possible to control the degree of distribution of the plasma passing through the through hole 32b. That is, as shown in (a) of FIG. 12, the upper diameter r1 and the lower diameter r2 of the through hole 32b are formed to be the same so that the plasma may be uniformly distributed. In addition, as shown in FIG. 12B, the lower diameter r2 of the through hole 32b is formed larger than the upper diameter r1 so that the plasma may be distributed more widely while passing through the through hole 32b. . In addition, as shown in (c) of FIG. 12, the upper diameter r1 of the through hole 32b is formed larger than the lower diameter r2 so that the plasma can be distributed more intensively while passing through the through hole 32b. have.

FIG. 12 is a diagram illustrating an arrangement of a power supply line for supplying power to a plurality of fan-shaped intermediate electrode members provided in the intermediate electrode plate.

Referring back to FIGS. 1 and 12, the frequency power generated from the power supply 40 is provided to the intermediate electrode 30 through the impedance matcher 43 and the current balance circuit 50. That is, when the intermediate electrode plate 32 having the plurality of intermediate electrode members 34 is installed in the plasma reactor 10, each of the intermediate electrode members 34 supplies current in a balanced manner through the current balance circuit 50. Receive. In the present invention, a plurality of current balancing circuits 50 are provided, and each current balancing circuit 50 includes at least two power feeding lines.

As shown in FIG. 12, first, the current balancing circuit 50 is connected to the power input terminal 34a of two adjacent intermediate electrode members 34 through two branched feed lines 60. Here, the feed line 60 is branched to the same number as the number of the intermediate electrode plate 32 provided in the intermediate electrode assembly 34. At this time, the plurality of current balancing circuits are installed between the feed lines branched from one feed line to supply a uniform current to each feed line node branched. In addition, the current balancing circuit may include a compensation circuit such as a compensation capacitor (not shown) for compensation of leakage current.

FIG. 13 is a diagram illustrating a state in which currents are balanced by interaction between adjacent power supply lines.

12 and 13, the current may be balanced by interaction between adjacent power supply lines 60. For example, the power supply line 60 connected to two adjacent intermediate electrode members 34 may be adjacent to each other so that current may be balanced from the power supply source 40 to each of the power supply lines 60 through interaction. have.

FIG. 14 illustrates a plasma reactor in which an intermediate electrode is grounded.

As shown in FIG. 14, the plasma reactor 10 ′ includes a reactor body 11, a gas supply unit 20, a capacitive coupling electrode 15, and an intermediate electrode 30. The capacitive coupling electrode 15 is provided below the gas supply unit 20 and insulated from the gas supply unit 20 by the insulating layer 17. Here, the capacitive coupling electrode 15 is connected to the power supply 40, the intermediate electrode 30 is connected to the ground. That is, a discharge is generated between the capacitive coupling electrode 15 supplied with the radio frequency power and the grounded intermediate electrode 30 to form a plasma. The plasma processes the substrate 13 to be processed, as described above.

The embodiment of the plasma reactor for generating a large-area plasma of the present invention described above is merely exemplary, and those skilled in the art to which the present invention pertains various modifications and equivalent other embodiments You can see that it is possible. Therefore, it will be understood that the present invention is not limited only to the form mentioned in the above detailed description. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims. It is also to be understood that the present invention includes all modifications, equivalents, and substitutes within the spirit and scope of the invention as defined by the appended claims.

1 is a cross-sectional view of a plasma reactor provided with a circular intermediate electrode plate according to a first preferred embodiment of the present invention.

2 to 4 are plan views illustrating intermediate electrode plates having through holes having various shapes according to the present invention.

5 is a view illustrating an intermediate electrode plate having a plurality of fan-shaped intermediate electrode members.

FIG. 6 is an exploded perspective view illustrating a state in which an intermediate electrode member of the intermediate electrode plate illustrated in FIG. 5 is separated.

7 is a cross-sectional view showing a state in which the intermediate electrode plate is mounted on the reactor body.

8 is a view using a power input terminal of the intermediate electrode plate to mount the intermediate electrode plate to the reactor body.

FIG. 9 is a plan view illustrating an intermediate electrode plate formed such that the size of the through hole becomes smaller from the outside to the inside.

FIG. 10 is a plan view illustrating an intermediate electrode plate formed such that the size of the through-hole increases gradually from the outside to the inside.

11 is a cross-sectional view illustrating a case in which the top and bottom sizes of the through holes are the same or different.

FIG. 12 is a diagram illustrating an arrangement of a power supply line for supplying power to a plurality of fan-shaped intermediate electrode members provided in the intermediate electrode plate.

FIG. 13 is a diagram illustrating a state in which currents are balanced by interaction between adjacent power supply lines.

FIG. 14 illustrates a plasma reactor in which an intermediate electrode is grounded.

* Description of the symbols for the main parts of the drawings *

8: vacuum pump 10, 10 ': plasma reactor

11; Reactor body 11a: jamming jaw

12: substrate support 13: substrate to be processed

15: capacitive coupling electrode 17: insulating layer

20: gas supply 21: gas inlet

23 gas injection port 30 intermediate electrode

32: intermediate electrode plate 32a, 34a: power input terminal

32b, 34b: through hole 34: intermediate electrode member

36: Frame 40: Power Source

43: impedance matcher 46: bias power supply

48: common impedance matcher 50: current balancing circuit

60: feed line

Claims (7)

A reactor body having a substrate support for supporting a substrate to be processed; A gas supply unit provided at an upper portion of the reactor body and configured to supply a process gas into the reactor body; A circular intermediate electrode provided to divide a space between the substrate support and the gas supply unit; And A plasma reactor generating a large-area plasma in which a discharge is generated between the grounded gas supply unit and the intermediate electrode including a power supply source for applying frequency power to the intermediate electrode. The method of claim 1, The intermediate electrode may include at least one power input terminal for inputting frequency power supplied from the power supply source; And And a plasma having a large area formed in a plate shape by including a plurality of through holes through which the generated plasma passes. The method of claim 2, The circular intermediate electrode is a plasma reactor for generating a large-area plasma formed by combining a plurality of fan-shaped intermediate electrode member. The method of claim 3, wherein The circular intermediate electrode generates a plasma of a large area further comprising a frame for mounting the plurality of intermediate electrode members. 5. The method of claim 4, The plasma reactor generates a large-area plasma including at least one current balancing circuit for automatically adjusting the mutual balance of the current supplied to the plurality of intermediate electrode members included in the intermediate electrode. The method of claim 5, The current balancing circuit includes a feed line separated into at least two, and a plasma reactor for generating a large-area plasma to automatically adjust the mutual balance of currents between adjacent feed lines is connected to the intermediate electrode member at the end of the feed line . A reactor body having a substrate support for supporting a substrate to be processed; A gas supply unit provided at an upper portion of the reactor body and configured to supply a process gas into the reactor body; A capacitively coupled electrode assembly provided below the gas supply part and having a plurality of capacitively coupled electrodes; A circular intermediate electrode provided to divide a space between the substrate support and the gas supply unit; And And a power supply source for applying frequency power to the capacitively coupled electrode assembly, wherein the plasma reactor generates a large-area plasma in which discharge is generated between the grounded intermediate electrode and the capacitively coupled electrode assembly.

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