KR100955207B1 - Capacitively coupled plasma reactor for processing dual substrates - Google Patents

Abstract

The capacitively coupled plasma reactor of the present invention includes a first capacitively coupled electrode assembly including a first plasma reactor, a second plasma reactor, and a plurality of capacitively coupled electrodes for inducing plasma discharge in the first plasma reactor, and the second plasma. A second capacitive coupling electrode assembly including a plurality of capacitive coupling electrodes for inducing plasma discharge in a reactor, a main power source for supplying radio frequency power, and receiving the radio frequency power provided from the main power source; And a divider circuit for distributing to the plurality of capacitively coupled electrodes of the first and second capacitively coupled electrode assemblies. According to the capacitively coupled plasma reactor, a large-area plasma can be generated uniformly by the plurality of capacitively coupled electrodes. In addition, by automatically balancing the current in driving the plurality of capacitively coupled electrodes in parallel, the capacitive coupling between the capacitively coupled electrodes can be uniformly controlled to uniformly generate high-density plasma. In addition, a large area of the plasma can be easily achieved by using a plurality of capacitively coupled electrodes. In addition, two or more large-area substrates can be processed at the same time, thereby increasing the substrate throughput per facility area.

Capacitively coupled plasma, plasma reactor, current balancing

Description

CAPACITIVELY COUPLED PLASMA REACTOR FOR PROCESSING DUAL SUBSTRATES}

The present invention relates to a capacitively coupled plasma reactor for dual substrate processing. Specifically, the present invention relates to a capacity for dual substrate processing capable of generating plasma of a large area more uniformly, thereby increasing plasma processing efficiency for a large-area target object. A coupled 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. The active gas is widely used in various fields and is typically used in a variety of semiconductor manufacturing processes such as etching, deposition, cleaning, ashing, and the like.

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 for manufacturing semiconductor circuits, the enlargement of glass substrates for manufacturing liquid crystal displays, 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.

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, productivity per unit area is one of the important factors affecting the price of the final product. Thus, technologies are being provided to effectively arrange the components of a production plant in a way to increase productivity per unit area. For example, a plasma reactor for processing two substrates in parallel is provided. However, most plasma reactors that process two substrates to be processed in parallel are equipped with two plasma sources, which does not substantially minimize process equipment.

If two or more plasma reactors are arranged vertically or horizontally in parallel, the common part of each component can be shared and two substrates can be processed in parallel by one plasma source. There will be several benefits to minimization.

As in any industry, many efforts are underway in the semiconductor industry to increase productivity. In order to increase productivity, production facilities basically need to be increased or improved. However, simply increasing the production equipment has a problem that not only the expansion cost of the process equipment but also the space equipment of the clean room increases, resulting in high cost.

It is an object of the present invention to provide a capacitively coupled plasma reactor capable of generating and maintaining a large area of plasma uniformly.

Another object of the present invention is to provide a capacitively coupled plasma reactor capable of uniformly generating high density plasma by uniformly controlling capacitive coupling between capacitively coupled electrodes.

Another object of the present invention is to provide a capacitively coupled plasma reactor capable of uniformly generating a high density plasma by uniformly controlling the current supply of the capacitively coupled electrode.

It is still another object of the present invention to provide a plasma reactor having a large substrate throughput per facility area, which is easy to make a large area, uniformly generate high-density plasma, and can simultaneously process two or more large-area target substrates.

One aspect of the present invention for achieving the above technical problem relates to a capacitively coupled plasma reactor. The capacitively coupled plasma reactor of the present invention comprises: a first plasma reactor; A second plasma reactor; A first capacitively coupled electrode assembly including a plurality of capacitively coupled electrodes to induce plasma discharge in the first plasma reactor; A second capacitively coupled electrode assembly including a plurality of capacitively coupled electrodes to induce plasma discharge in the second plasma reactor; A main power source for supplying radio frequency power; And a divider circuit for receiving the radio frequency power provided from the main power supply and distributing the plurality of capacitively coupled electrodes of the first and second capacitively coupled electrode assemblies.

In one embodiment, an impedance matcher is configured between the main power supply and the divider circuit to perform impedance matching.

In one embodiment, the divider circuit includes a current balance circuit that adjusts the balance of current supplied to the plurality of capacitively coupled electrodes of the first and second capacitively coupled electrode assemblies.

In an embodiment, the current balancing circuit includes a plurality of transformers for balancing current while driving the plurality of capacitively coupled electrodes of the first and second capacitively coupled electrode assemblies in parallel.

In one embodiment, the primary side of the plurality of transformer is connected in series between the power input terminal and the ground to which the radio frequency is input, the secondary side corresponds to the plurality of capacitive coupling electrode of the first and second capacitive coupling electrode assembly Is connected.

In an embodiment, the secondary sides of the plurality of transformers each include a grounded intermediate tab, one end of the secondary side outputs a constant voltage and the other end of a negative voltage, and the constant voltage is a constant voltage of the plurality of capacitive coupling electrodes. The negative voltage as an electrode is provided to negative voltage electrodes of the plurality of capacitively coupled electrodes.

In one embodiment, the current balancing circuit includes a voltage level adjusting circuit that can vary the current balancing adjusting range.

In one embodiment, the current balancing circuit comprises a compensation circuit for compensation of leakage current.

In one embodiment, the current balancing circuit includes a protection circuit for preventing damage due to transient voltage.

In one embodiment, the plurality of capacitively coupled electrodes includes a conductor region and an insulator region.

In one embodiment, the first and second capacitively coupled electrode assemblies include an insulating layer configured between each of the plurality of capacitively coupled electrodes.

In one embodiment, the first and second capacitively coupled electrode assemblies include an electrode mounting plate on which each of the plurality of capacitively coupled electrodes is mounted.

In one embodiment, each electrode mounting plate of the first and second capacitively coupled electrode assembly includes a plurality of gas injection holes, the gas into the first and second plasma reactor through the gas injection holes It includes a gas supply for supplying.

In one embodiment, the gas supply unit comprises a plurality of gas supply pipes.

In one embodiment, the plurality of gas supply pipes each include a control valve that can independently control the gas supply flow rate.

In one embodiment, the first and second plasma reactors have a support in which the substrate to be processed is placed, and the support is either biased or unbiased.

In one embodiment, the support is biased but biased by a single frequency power supply or two or more different frequency power supplies.

In one embodiment, the support includes an electrostatic chuck.

In one embodiment, the support comprises a heater.

In an embodiment, the plurality of capacitively coupled electrodes includes a plurality of constant voltage electrodes and a plurality of negative voltage electrodes, and the arrangement structure of the constant voltage electrode and the negative voltage electrode is an alternating linear arrangement structure, an array having a matrix form. And at least one array structure selected from the structure, the alternating spiral arrangement structure, and the mutually alternating concentric arrangement structure.

In one embodiment, the constant voltage electrode and the plurality of negative voltage electrodes have at least one structure selected from a barrier structure, a flat plate structure, a protrusion structure, a column structure, an annular structure, a spiral structure, a linear structure.

According to the capacitively coupled plasma reactor of the present invention, a large-area plasma can be uniformly generated by the plurality of capacitively coupled electrodes. In addition, by automatically balancing the current in driving the plurality of capacitively coupled electrodes in parallel, the capacitive coupling between the capacitively coupled electrodes can be uniformly controlled to uniformly generate high-density plasma. In addition, a large area of the plasma can be easily achieved by using a plurality of capacitively coupled electrodes. In addition, two or more large-area substrates can be processed at the same time, thereby increasing the substrate throughput per facility 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 a cross-sectional view of a plasma reactor according to a preferred embodiment of the present invention.

Referring to FIG. 1, an inductively coupled plasma reactor according to a preferred embodiment of the present invention includes the first and second plasma reactors 10 and 15 and the first and second plasma reactors 10 and 15 configured in parallel. First and second capacitively coupled electrode assemblies 30, 35 for respectively inducing plasma discharge. The gas supply unit 20 is provided between the first and second capacitively coupled electrode assemblies 30 and 35. In the first and second plasma reactors 10 and 15, the supports 12 and 17, on which the substrates 13 and 18 are placed, are opposed to the first and second capacitively coupled electrode assemblies 30 and 35. It is installed by the side wall. The gas supply unit 20 is configured between the first and second capacitively coupled electrode assemblies 30 to inject a gas provided from a gas park (not shown) into the gas of the first and second capacitively coupled electrode assemblies 30 and 35. The holes 32 and 37 are supplied into the first and second plasma reactors 10 and 15. The radio frequency power generated from the main power air raid source 40 is a plurality of capacitively coupled electrodes provided in the first and second capacitively coupled electrode assemblies 30 and 35 through the impedance matcher 41 and the distribution circuit 50. (31, 33, 36, 38) is supplied to induce capacitively coupled plasma inside the first and second plasma reactors (10, 15). Plasma processing is performed on the substrates 13 and 18 by the plasma generated in the first and second plasma reactors 10 and 15.

The first and second plasma reactors 10, 15 are provided with reactor bodies 11, 16 and supports 12, 17 on which substrates 13, 18 to be processed are placed. The reactor bodies 11 and 16 can be rebuilt from metallic materials such as aluminum, stainless steel and copper. Or may be rewritten with coated metal, for example anodized aluminum or nickel plated aluminum. Or it may be rewritten as a refractory metal. Alternatively, it is also possible to reconstruct the reactor bodies 11, 16 entirely or in part from electrically insulating materials such as quartz, ceramics. As such, the reactor bodies 11, 16 may be rebuilt from any material suitable for the intended plasma process to be performed. The structure of the reactor bodies 11 and 16 may have a structure suitable for the uniform generation of the plasma, for example, a circular structure or a square structure, or any other structure depending on the substrates 13 and 18 to be processed.

The substrates 13 and 18 to be processed are, for example, substrates such as wafer substrates, glass substrates, plastic substrates, and the like for manufacturing various devices such as semiconductor devices, display devices, solar cells, and the like. The first and second plasma reactors 10, 15 are connected to a vacuum pump (not shown). One vacuum pump can be used to have a common exhaust structure, or a separate vacuum pump can be used to have each exhaust structure. In the embodiment of the present invention, the first and second plasma reactors 10 and 15 are subjected to plasma processing on the substrates 13 and 18 under low pressure below atmospheric pressure. However, the capacitively coupled plasma reactor of the present invention can also be used as an atmospheric plasma processing system for processing a substrate under atmospheric pressure.

2 is a perspective view illustrating a capacitively coupled electrode assembly and a gas supply unit;

Referring to FIG. 2, the gas supply unit 20 is installed between the first and second capacitive coupling electrode assemblies 30 and 35. The gas supply unit 20 includes a plurality of gas supply pipes 21 connected to a gas supply source (not shown). The plurality of gas supply pipes 21 are provided with control valves 24 that can control the gas supply flow rates independently of each other. Alternatively, the gas supply flow rate may be collectively controlled with respect to the plurality of gas supply pipes 21. Alternatively, the plurality of gas supply pipes 21 may be configured to enable control of the total and individual gas supply flow rates.

In the plurality of gas supply pipes 21, a plurality of gas injection ports 22 and 23 are connected to the plurality of gas injection holes 32 and 37 of the first and second electrode mounting plates 34 and 39. The gas provided from the gas supply source is evenly distributed through the plurality of gas supply pipes 21 so that the first and second plasma reactors are provided through the plurality of gas inlets 22 and 23 and the plurality of gas injection holes 32 and 37 corresponding thereto. It is sprayed evenly to the inside of (10, 15). The plurality of gas supply pipes 21 may be divided into two groups to form separate gas supply channels. It is possible to increase the uniformity of the plasma treatment by separating and supplying different gases.

The first and second capacitively coupled electrode assemblies 30 and 35 may include a plurality of capacitively coupled electrodes 31, 33, and 36 for inducing capacitively coupled plasma discharges in the first and second plasma reactors 10 and 15. , 38). A plurality of capacitively coupled electrodes 31, 33, 36, 38 are mounted on the respective electrode mounting plates 34, 39. The electrode mounting plates 34, 38 oppose the supports 12, 17 of the first and second plasma reactors 10, 15, and the plurality of capacitively coupled electrodes 31, 33, 36, 38 are horizontal or It is arranged vertically and installed in the electrode mounting plates 34 and 39. The plurality of capacitively coupled electrodes 31, 33, 36, and 38 have a structure in which the plurality of constant voltage electrodes 33 and 38 and the negative voltage electrodes 31 and 36 are alternately arranged in parallel. The plurality of capacitively coupled electrodes 31 and 33 have a linear barrier structure protruding from the electrode mounting plate 34. As illustrated in FIG. 3, the plurality of capacitive coupling electrodes 31, 33, 36, and 38 may be configured of a conductor region 71 and an insulator region 71 surrounding the outside thereof. Alternatively, only the conductor region 71 may be provided. The shape and arrangement of the plurality of capacitive coupling electrodes 31, 33, 36, 38 may be variously modified as described below.

The electrode mounting plates 34 and 39 are provided with a plurality of gas injection holes 32 and 37. The plurality of gas injection holes 32 and 37 are configured at a predetermined interval between the plurality of capacitively coupled electrodes 31, 33, 36, and 38. The electrode mounting plates 34 and 39 may be made of a metal, a nonmetal, or a mixed material thereof. Of course, when the electrode mounting plates 34 and 39 are made of a metal material, the electrode mounting plates 34 and 39 have an electrically insulating structure between the capacitive coupling electrodes 31, 33, 36, and 38. The electrode mounting plates 34 and 39 are installed to form one sidewall of the reactor bodies 11 and 16, but may be installed along both the ceiling and the bottom side walls of the reactor bodies 11 and 16 to increase plasma treatment efficiency. Alternatively, one side wall of the reactor bodies 11 and 16 and both the ceiling and the bottom side wall surfaces of the reactor bodies 11 and 16 may be installed. Although not shown in detail, the electrode mounting plates 34 and 39 may include cooling channels or heating channels for proper temperature control.

4 through 10 are cross-sectional views of the capacitively coupled electrode assembly showing various modifications of the capacitively coupled electrode.

First, as shown in FIG. 4, the capacitive coupling electrodes 31, 33, 36, and 38 have a barrier structure, and a cross-section thereof may have a 'T' type structure, and the head portion thereof may have an electrode mounting plate 34. It may be installed to be fixed to the) or to have the reverse arrangement position. The capacitive coupling electrodes 31, 33, 36, and 38 may have a plate-like structure having a narrow width, as shown in FIG. 5. As shown in FIG. 6 or 7, the capacitive coupling electrodes 31, 33, 36, and 38 may have a triangular or inverted triangular structure. Alternatively, as shown in FIGS. 8 to 10, the rod-shaped structure may have a cylindrical rod-shaped structure, a divided elliptic structure or a standing elliptic structure. As such, the capacitive coupling electrodes 31, 33, 36, and 38 may have various structures such as a circular, elliptical, and polygonal structures.

11 to 21 are bottom plan views of capacitively coupled electrode assemblies showing various modifications of the planar structure and the planar arrangement of the capacitively coupled electrodes.

First, as shown in FIG. 11, the plurality of constant voltage electrodes 33 and 38 and the plurality of negative voltage electrodes 31 and 36 constituting the plurality of capacitive coupling electrodes 31, 33, 36, and 38 alternate with each other. The plurality of gas injection holes (32, 37) may be arranged between them. As shown in FIG. 12 or 13, the plurality of constant voltage electrodes 33 and 38 and the negative voltage electrodes 31 and 36 have the same electrodes arranged in the same column (or row) in a structure divided into predetermined lengths and alternately arranged with each other. It may have a structure (Fig. 12) or a structure arranged in a matrix (Fig. 13). As shown in FIG. 14 or FIG. 15, the plurality of capacitively coupled electrodes 31, 33, 36, and 38 may be composed of a plurality of square or circular flat area electrodes. As illustrated in FIG. 16, the plurality of capacitively coupled electrodes 31, 33, 36, and 38 may have a columnar structure such as a cylinder. 17 to 21, the plurality of capacitively coupled electrodes 31, 33, 36, and 38 may have a flat plate spiral structure or a concentric circle structure alternately arranged with each other. In this structure, the plurality of capacitively coupled electrodes 31, 33, 36, and 38 may be composed of only one constant voltage electrode 33 and 38 and the negative voltage electrodes 31 and 36.

As described above, the plurality of capacitively coupled electrodes 31, 33, 36, 38 may have at least one structure selected from a barrier structure, a plate structure, a protrusion structure, a column structure, a concentric or annular structure, a spiral structure, and a linear structure. Can be. The mutual arrangement of the plurality of constant voltage electrodes 33 and 38 and the negative voltage electrodes 31 and 36 may also include an alternate linear arrangement, a matrix arrangement, an alternate spiral arrangement, and an alternate concentric arrangement. It may have one or more array structures selected from a variety of array structures, such as. Although not shown in detail, an insulating layer may be formed between the plurality of capacitively coupled electrodes 31, 33, 36, and 38.

Again, referring to FIG. 1, the support units 12 and 17 for supporting the substrates 13 and 18 are provided inside the first and second plasma reactors 10 and 15. Substrate supports 12, 17 are connected to and biased to bias power sources 42, 43, 45, 46. For example, two bias power sources 42, 43, 45, 46, which supply different radio frequency power, are electrically connected to the substrate supports 12, 17 through impedance matchers 44, 47. Biased. The dual bias structure of the substrate supports 12 and 17 may facilitate plasma generation inside the first and second plasma reactors 10 and 15, and further improve plasma ion energy control to improve process productivity. Alternatively, it may be modified to a single bias structure. Alternatively, the supports 12 and 17 may be modified to have a zero potential without supplying bias power. The substrate supports 12 and 17 may include an electrostatic chuck. Alternatively, the substrate supports 12 and 17 may include a heater.

The plurality of capacitive coupling electrodes 31, 33, 36, and 38 are driven by receiving the radio frequency power generated from the main power supply 40 through the impedance matcher 41 and the distribution circuit 50. 2 Induces capacitively coupled plasma inside the plasma reactor (10, 15). The main power supply 40 may be configured using a radio frequency generator capable of controlling the output power without a separate impedance matcher. The distribution circuit 50 distributes the radio frequency power provided from the main power supply 40 to the plurality of capacitive coupling electrodes 31, 33, 36, 38 to be driven in parallel. Preferably, the distribution circuit 50 is composed of a current balancing circuit so that the currents supplied to the plurality of capacitive coupling electrodes 31, 33, 36, 38 are automatically balanced. In the capacitively coupled plasma reactor of the present invention, a large-area plasma can be uniformly generated by the plurality of capacitively coupled electrodes 31, 33, 36, and 38. In addition, it is possible to generate and maintain the plasma of a large area more uniformly by automatically balancing the currents in parallel driving the plurality of capacitive coupling electrodes.

22 is a diagram illustrating an example in which a distribution circuit is configured as a current balancing circuit.

Referring to FIG. 22, the distribution circuit 50 includes a plurality of transformers 52 that drive a plurality of capacitively coupled electrodes 31, 33, 36, and 38 in parallel and balance current. The primary side of the plurality of transformers 52 is connected in series between the power input terminal to which the radio frequency is input and ground, and one end of the secondary side is connected to the plurality of capacitive coupling electrodes 31, 33, 36, 38, and the other end thereof. Are commonly grounded. The plurality of transformers 52 equally divide the voltage between the power input terminal and the ground and divide the divided plurality of divided voltages among the plurality of capacitive coupling electrodes 31, 33, 36, 38 corresponding to the constant voltage electrodes 33, 38. ) Among the plurality of capacitively coupled electrodes 31, 33, 36, and 38, the negative voltage electrodes 31 and 36 are commonly grounded.

Since the current flowing to the primary side of the plurality of transformers 52 is the same, the power supplied to the plurality of constant voltage electrodes 33 and 38 is also the same. When the impedance of any one of the plurality of capacitive coupling electrodes 31, 33, 36, 38 is changed to change the amount of current, the plurality of transformers 52 may interact with each other to achieve a current balance. Thus, the currents supplied to the plurality of capacitive coupling electrodes 31, 33, 36, 38 are continuously and automatically adjusted uniformly with each other. In the plurality of transformers 52, the winding ratios of the primary side and the secondary side are basically set to 1: 1, but this can be changed.

Although the current balance circuit 50 is not shown in the drawings, the current balance circuit 50 may include a protection circuit for preventing a transient voltage from being generated in the plurality of transformers 52. The protection circuit prevents any one of the plurality of transformers 52 from being electrically open to increase the transient voltage on the transformer. The protection circuit of this function may be implemented by connecting a varistor to both ends of each primary side of the plurality of transformers 52, or may be implemented by using a constant voltage diode such as a Zener diode. . In addition, a compensation circuit such as a compensation capacitor 51 for compensating for the leakage current may be added to each transformer 52 in the current balancing circuit 50.

23 to 28 show various modifications of the distribution circuit.

Referring to FIG. 23, one variation of the current balancing circuit 50 includes an intermediate tap in which the secondary sides of the plurality of transformers 52 are grounded, respectively, and outputs a constant voltage at one end of the secondary side and a negative voltage at the other end thereof. The constant voltage is provided to the constant voltage electrodes 33 and 38 of the plurality of capacitively coupled electrodes, and the negative voltage is provided to the negative voltage electrodes 31 and 36 of the plurality of capacitively coupled electrodes.

Referring to FIG. 24, another variation of the current balancing circuits 50a, 50b may be composed of separate first and second current balancing circuits 50a, 50b. The first and second current balancing circuits 50a and 50b are connected in parallel to the impedance matcher 41. The first current balancing circuit 50a is connected to the plurality of capacitive coupling electrodes 31 and 33 of the first capacitive coupling electrode assembly 30 and the second current balancing circuit 50b is connected to the second capacitive coupling electrode assembly 35. Each of the capacitive coupling electrodes 36 and 38 corresponds to each other.

25 and 26, another variation of the current regulation circuit 50 may include a voltage level adjustment circuit 60 that can vary the current balance adjustment range. The voltage level adjustment circuit 60 includes a coil 61 having a multi tap and a multi tap switching circuit 62 for connecting one of the multi taps to ground. The voltage level adjusting circuit 60 applies a voltage level which is varied according to the switching position of the multi-tap switching circuit 62 to the current balancing circuit 50, and the current balancing circuit 50 is the voltage level adjusting circuit 60. The current balance adjustment range is changed by the voltage level determined by. 27 and 28, even when the first and second current balancing circuits 50a and 50b are configured, the voltage level adjusting circuits 60a and 60b may be provided in the same manner.

The embodiment of the capacitively coupled plasma reactor of the present invention described above is merely illustrative, and it is well understood that various modifications and equivalent other embodiments are possible to those skilled in the art to which the present invention pertains. You will know. 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.

   The capacitively coupled plasma reactor of the present invention can be very usefully used in plasma processing processes for forming various thin films, such as the manufacture of semiconductor integrated circuits, the manufacture of flat panel displays, and the manufacture of solar cells. In particular, the capacitively coupled plasma reactor of the present invention can generate a large area of plasma uniformly by a plurality of capacitively coupled electrodes. In addition, it is possible to generate and maintain the plasma of a large area more uniformly by automatically balancing the currents in parallel driving the plurality of capacitive coupling electrodes.

1 is a cross-sectional view of a plasma reactor according to a preferred embodiment of the present invention.

2 is a perspective view illustrating a capacitively coupled electrode assembly and a gas supply unit;

3 is a cross-sectional view of the capacitive coupling electrode.

4 through 10 are cross-sectional views of the capacitively coupled electrode assembly showing various modifications of the capacitively coupled electrode.

11 to 21 are bottom plan views of capacitively coupled electrode assemblies showing various modifications of the planar structure and the planar arrangement of the capacitively coupled electrodes.

22 is a diagram illustrating an example in which a distribution circuit is configured as a current balancing circuit.

23 to 28 show various modifications of the distribution circuit.

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

8: vacuum pump 10: plasma reactor

11: reactor body 12: support

13: substrate to be processed 20: gas supply part

21: gas inlet 22: gas distribution plate

23: gas inlet 30: capacitive coupling electrode assembly

31, 33: capacitive coupling electrode 32: gas injection hole

34: electrode mounting plate 40: main power supply

41: impedance matcher 42, 43: bias power supply

44: impedance matcher 50: distribution circuit

51: compensation capacitor 52: transformer

53: middle tap 60: voltage level adjustment circuit

61: coil 62: multi-tap switching circuit

70: insulator region 71: conductor region

Claims (21)

A first plasma reactor; A second plasma reactor; A first capacitively coupled electrode assembly including a plurality of capacitively coupled electrodes to induce plasma discharge in the first plasma reactor; A second capacitively coupled electrode assembly including a plurality of capacitively coupled electrodes to induce plasma discharge in the second plasma reactor; A main power source for supplying radio frequency power; And And a divider circuit for receiving the radio frequency power provided from said main power source and distributing to a plurality of capacitively coupled electrodes of said first and second capacitively coupled electrode assemblies. The method of claim 1, And a impedance matcher configured between the main power supply and the distributor circuit to perform impedance matching. The method of claim 1, Wherein the divider circuit comprises a current balancing circuit for adjusting the balance of current supplied to the plurality of capacitively coupled electrodes of the first and second capacitively coupled electrode assemblies. The method of claim 3, The current balancing circuit includes a plurality of transformers in parallel driving the plurality of capacitively coupled electrodes of the first and second capacitively coupled electrode assembly to balance the current. The method of claim 4, wherein The primary side of the plurality of transformers is connected in series between a power input terminal to which the radio frequency is input and ground, and the secondary side is a capacitively coupled plasma corresponding to a plurality of capacitively coupled electrodes of the first and second capacitively coupled electrode assemblies. Reactor. The method of claim 5, Secondary sides of the plurality of transformers each include a grounded middle tab, one end of the secondary side outputs a constant voltage and the other end a negative voltage, The constant voltage is a constant voltage electrode of the plurality of capacitively coupled electrodes, and the negative voltage is provided to the negative voltage electrodes of the plurality of capacitively coupled electrodes. The method of claim 3, Wherein said current balancing circuit includes a voltage level adjusting circuit capable of varying a current balancing adjusting range. The method of claim 3, Wherein said current balancing circuit comprises a compensation circuit for compensating for leakage current. The method of claim 3, The current balancing circuit includes a protection circuit for preventing damage caused by transient voltage. The method of claim 1, And said plurality of capacitively coupled electrodes comprises a conductor region and an insulator region. The method of claim 1, Wherein the first and second capacitively coupled electrode assemblies comprise an insulating layer configured between each of the plurality of capacitively coupled electrodes. The method of claim 1, Wherein said first and second capacitively coupled electrode assemblies comprise an electrode mounting plate on which each of a plurality of capacitively coupled electrodes is mounted. The method of claim 12, Each electrode mounting plate of the first and second capacitively coupled electrode assemblies includes a plurality of gas injection holes, And a gas supply unit supplying gas into the first and second plasma reactors through the gas injection holes. The method of claim 13, The gas supply unit capacitively coupled plasma reactor comprising a plurality of gas supply pipes. The method of claim 14, The plurality of gas supply pipes each capacitively coupled plasma reactor including a control valve that can independently control the gas supply flow rate. The method of claim 1, Wherein said first and second plasma reactors have a support on which a substrate to be processed is placed, and said support is either biased or unbiased. The method of claim 16, Wherein said support is biased, but biased by a single frequency power supply or by two or more different frequency power supplies. The method of claim 16, The support is capacitively coupled plasma reactor comprising an electrostatic chuck. The method of claim 17, The support is capacitively coupled plasma reactor comprising a heater. The method of claim 1, The plurality of capacitively coupled electrodes includes a plurality of constant voltage electrodes and a plurality of negative voltage electrodes, The array structure of the constant voltage electrode and the negative voltage electrode is a capacitively coupled plasma reactor having one or more array structures selected from an alternating linear array structure, a matrix-like array structure, an mutually alternate spiral array structure, and an alternate alternating concentric array structure. . The method of claim 20, And the constant voltage electrode and the plurality of negative voltage electrodes have at least one structure selected from a barrier structure, a flat structure, a protrusion structure, a pillar structure, an annular structure, a spiral structure, and a linear structure.

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