KR20060066794A - Inductive plasma source with external discharge bridge - Google Patents

Abstract

The induction plasma source of the present invention has at least one external discharge bridge on the top surface of the plasma reaction chamber. The external discharge bridge is composed of a nonconductor. Magnetic cores with winding coils connected to the power supply are mounted on both sides of the external discharge bridge. A cooling tube is installed between the magnetic core and the external discharge bridge. The cooling tube is composed of a conductor, and two ignition electrodes connected to both cooling tubes are disposed opposite to each other on an external discharge bridge. The upper surface of the plasma reaction chamber is provided with a cooling chamber. The cooling tube installed in the external discharge bridge and the cooling chamber provided on the upper surface of the plasma reaction chamber prevent heat generation of the external discharge bridge and the plasma reaction chamber. By configuring the ignition electrode by using a cooling tube installed in the external discharge bridge, it is not necessary to have a separate ignition electrode and the ignition power can increase the efficiency of equipment configuration. A high density uniform and wide volume of plasma can be obtained inside the plasma reaction chamber by providing a plasma diffusion means having a diffusion inductor, a baffle plate and a plurality of electrode pairs inside the plasma reaction chamber.

Plasma, inductively coupled plasma, ICP

Description

INDUCTIVE PLASMA SOURCE WITH EXTERNAL DISCHARGE BRIDGE}             

1 is a perspective view of a plasma processing chamber in accordance with a preferred embodiment of the present invention;

FIG. 2 shows a coupling structure of the external discharge bridge and the plasma reaction chamber of FIG. 1; FIG.

3 to 5 are perspective, plan and sectional views of the external discharge bridge of FIG. 1;

6 is a sectional view showing a nozzle structure of a gas inlet of an external discharge bridge;

7 is a cross-sectional view showing an example in which the nozzle structure of the gas inlet is modified.

8 to 11 are perspective and plan views showing various modified structures of the ignition electrode;

12 is an overall cross-sectional view of the plasma processing chamber of FIG. 1;

13 is a perspective view of the diffusion inductor of FIG. 12;

14-16 are perspective, top, and cross-sectional views of an external discharge bridge in which the magnetic core and the cooling tube are mounted horizontally with the top surface of the plasma reaction chamber;

17 and 18 are perspective views of a plasma processing chamber equipped with a plurality of external discharge tube bridges;

19 and 20 are a perspective view and a sectional view of an external discharge bridge provided with a gas connection pipe at the gas inlet;

21 is a perspective view of an external discharge bridge having a gas connecting tube installed in an orthogonal form;

22 is a perspective view of a plasma processing chamber having a cooling chamber on an upper surface of the plasma reaction chamber;

FIG. 23 is a view illustrating a coupling structure of the external discharge bridge and the plasma reaction chamber of FIG. 22;

24 and 25 are perspective and plan views of the external discharge bridge;

FIG. 26 is a cross sectional view showing a structure in which an external discharge bridge is coupled to an upper surface of a plasma reaction chamber; FIG.

27 is a cross sectional view of the plasma processing chamber in which a pair of diffusion electrodes is provided inside the plasma reaction chamber;

FIG. 28 is a cross-sectional view taken along the line A-A of FIG. 27; FIG.

29 is a flowchart of a power supply control procedure by the phase / voltage control section;

30A to 30C are waveform diagrams of power supplied to the internal diffusion electrode pairs according to the power supply control procedure.

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

10: plasma reaction chamber 19: diffusion inductor

20: external discharge bridge 21: gas inlet

24a, 24b: gas outlet 25: bridge body

30a, 30b: magnetic core 31a, 31b: winding coil

40a, 40b: cooling tube 45a, 45b: ignition electrode

50: common flange 54: cooling chamber

The present invention relates to a plasma source, and more particularly, to an inductively coupled plasma source having an external discharge tube bridge.

Plasma is a highly ionized gas containing the same number of positive ions and electrons. Plasma sources are used in a variety of industries. For example, in the production process of semiconductor devices, plasma is used for cleaning, etching, and deposition processes of semiconductor wafers and liquid crystal display devices.

ICP (inductive coupled plasma) or TCP (transformer coupled plasma) generation technology has been widely studied in this application field. The RF ICP scheme provides the advantage of having no electrodes in contact with the plasma in providing electromagnetic energy for plasma generation. A technique for inductively coupled discharge for plasma etching and resist stripping is disclosed in US Pat. No. 4,431,898, issued to Alan Alllaneberg et al. On February 14, 1984, as a technique for an initial ICP-type plasma source.

In the production of semiconductor devices, there is a need for a plasma source having a wider volume, uniformity, and higher density capable of effectively processing a large size wafer. Also in the production of liquid crystal display panels, a plasma source that enables the processing of large size liquid crystal display panels is required.

In US Patent No. 6392351, issued to Egeny Vanceco, on May 21, 2002, a technique is disclosed for an inductive RF plasma source having an external discharge bridge. And US Patent Publication No. 6432260, issued to Leonard J. Mahoni et al. On August 13, 2002, discloses an inductively coupled ring-plasma source device for process gases and materials and a method thereof.

In the techniques disclosed in US Pat. Nos. 6,337,351 and 6432260, a plasma is generated by using a C-shape bridge coupled to a transformer. However, in order to obtain a high-density plasma with a wide volume, high energy must be supplied to the transformer, and thus high heat is generated, resulting in thermal damage to the upper surfaces of the C-shaped bridge and the chamber housing. In addition, the connection structure of the C-shaped bridge and the working chamber (working chamber or process chamber) alone is difficult to uniformly diffuse the plasma gas while maintaining a high density inside the working chamber.

Accordingly, an object of the present invention has been proposed to solve the above-mentioned problems, and to provide an induction plasma source capable of obtaining a wide volume plasma having high uniformity.

Another object of the present invention is to provide an induction plasma source capable of preventing thermal damage from occurring in the external discharge bridge and the plasma reaction chamber.

According to a feature of the present invention for achieving the object of the present invention as described above, an induction plasma source comprises: a plasma reaction chamber having at least two holes in an upper surface and a susceptor in which a workpiece to be processed is placed; ; At least one external discharge bridge positioned outside the plasma reaction chamber and coupled to the at least two holes; A power supply for supplying RF power; At least one magnetic core mounted to surround an external discharge bridge, the magnetic core having an external discharge bridge and a winding coil connected to a power supply source for generating an electromotive force for exciting plasma into the plasma reaction chamber; At least one cooling tube installed between the external discharge bridge and the magnetic core.

In a preferred embodiment of the present invention, the external discharge bridge is composed of a non-conductor.

In a preferred embodiment of the invention, the external discharge bridge is: C-shaped hollow with a first bridge lag connected to one hole of the plasma reaction chamber and a second bridge lag connected to the other hole. Bridge body; A gas inlet protruding from the upper center portion of the bridge body to receive a reaction gas supplied from a gas source; And first and second gas outlets inserted into the two holes as respective ends of the first and second bridge lags. The gas inlet and the first and second gas outlets have a flange structure. The gas inlet includes a nozzle structure and a structure in which the inner diameter is smoothly increased / decreased, or gradually increased / decreased.

In a preferred embodiment of the present invention, the external discharge bridge further comprises a gas connection tube connected to the center of the tube at the top of the gas inlet and allowing a reactive gas supplied from the gas source to be provided to the gas inlet. Both ends of the gas connecting pipe and the first and second gas outlets have an inductively coupled plasma source having a flange structure.

According to a preferred embodiment of the present invention, the cooling tube of claim 1, wherein the cooling tube body surrounding the external discharge bridge; A coolant inlet and a coolant outlet connected to the cooling tube body; At least one guide plate is installed inside the cooling tube body to guide the flow of the cooling water from the cooling water inlet to the cooling water outlet.

In a preferred embodiment of the present invention, the external discharge bridge includes: a first bridge lag connected to one hole of the plasma reaction chamber; A C-shaped hollow bridge body having a second bridge lag connected to the other hole, the magnetic core comprising: a first magnetic core mounted to the first bridge lag; A second magnetic core installed on a second bridge lag, wherein the cooling tube comprises: a first cooling tube installed between the first bridge lag and the first magnetic core; And a second cooling conduit provided between the second bridge lag and the second magnetic core.

The first cooling tube and the second cooling tube are composed of a conductor, and the first cooling tube further includes a first ignition electrode electrically connected to each other, and the second cooling tube further includes a second ignition electrode electrically connected thereto. First and second ignition electrodes are disposed in the external discharge bridge; Each of the first and second magnetic cores has winding coils installed so that induced electromotive force of opposite polarity is generated, and the induced voltage of opposite polarity is generated by the induced electromotive force of opposite polarity of the first cooling tube and the second cooling tube. And the first and second ignition electrodes cause ignition for plasma discharge.

The first and second ignition electrodes extend from the first and second cooling tubes and are disposed to face each other with an external discharge bridge therebetween. Alternatively, the first and second ignition electrodes are coupled to the tube of the external discharge bridge in a ring shape, the first ignition electrode is installed close to the second cooling tube and the second ignition electrode is installed close to the first cooling tube.

In a preferred embodiment of the present invention, the plasma reaction chamber includes a baffle plate disposed across the inner top region and having a plurality of holes therethrough. The plasma reaction chamber is generally solid and has an open top, and is installed between the inner ceiling and the baffle plate of the plasma reaction chamber to induce the plasma gas, which is input through the external discharge bridge, to diffuse evenly into the inner lower portion of the plasma reaction chamber. Diffusion diffuser.

In a preferred embodiment of the present invention, a bias power supply for supplying a bias power to the susceptor.

In a preferred embodiment of the invention, the plasma reaction chamber includes a cooling chamber formed on the outer upper surface to include at least two holes. The external discharge bridge includes a C-shaped hollow bridge body having a first bridge lag connected to one hole of the plasma reaction chamber and a second bridge lag connected to the other hole; Each end of the first and second bridge lags has first and second gas outlets respectively connected to the two holes, the first and second gas outlets covering and sealing the upper portion of the cooling chamber. Has

The cooling chamber may include first and second o-rings installed between the common flange and the two holes; And a third o-ring installed between the common flange and the plasma reaction chamber. The cooling chamber includes a coolant inlet and a coolant outlet formed on a common flange. The external discharge bridge includes a gas inlet that protrudes from the upper center portion of the bridge body to receive a reactive gas supplied from a gas source.

In a preferred embodiment of the present invention, the apparatus further includes plasma diffusion means for inducing an acceleration path of the plasma ion particles to uniformly diffuse the plasma gas in the plasma reaction chamber. The plasma diffusion means includes: a first electrode pair having two plate electrodes disposed to face each other on an inner wall of the plasma reaction chamber; A second electrode pair having two plate electrodes disposed to face each other on an inner side wall of the plasma reaction chamber and disposed to be orthogonal to the first electrode pair; A first power supply for supplying a first frequency to the first electrode pair; A second power supply source supplying a second frequency to the second electrode pair; And a phase / voltage control unit controlling the first and second power sources to control phases and voltages of the first and second frequencies. Each of the electrodes of the first and second electrode pairs is installed on an inner wall of the plasma reaction chamber via an insulator.

The control of the first and second power sources of the phase / voltage control includes: initializing the first and second frequencies to have a first phase difference; Outputting first and second frequencies having a first phase difference as a starting frequency; Controlling the phase such that the first and second frequencies have a second phase difference; And outputting first and second frequencies having a second phase difference at a stable frequency. And changing the voltage level from the first voltage level to the second voltage level when the stable frequency is output.

The embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be construed as being limited by the embodiments described below. This embodiment is provided to explain more clearly the present invention to those skilled in the art.

(Example)

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a perspective view of a plasma processing chamber 10 according to a preferred embodiment of the present invention, Figure 2 is a view showing a coupling structure of the external discharge bridge 20 and the plasma reaction chamber 10 of FIG.

Referring to the drawings, an induction plasma source according to a preferred embodiment of the present invention includes a process plasma reaction chamber 10 and an external discharge bridge 20. The external discharge bridge 20 is vacuum-insulated by the O-rings 13a and 13b in the two holes 12a and 12b formed in the outer upper surface 11 of the plasma reaction chamber 10, respectively.

3 to 5 are perspective, plan and cross-sectional views of the external discharge bridge 20 of FIG. 1.

Referring to the drawings, the external discharge bridge 20 has a hollow bridge body 25 having a C-shape as a whole. The bridge body 25 is provided with a first bridge leg 23a and a second bridge lag 23b, which are bent at 'A' on both sides, and have a C-shape as a whole. The ends of the first and second bridge lags 23a and 23b constitute the first and second gas outlets 24a and 24b, respectively, and are inserted into and mounted in the two holes 12a and 12b, respectively. In addition, a gas inlet 21 protruding upward and receiving a reaction gas supplied from a gas supply source (not shown) is provided at an upper center portion of the bridge body 25. In this embodiment, the external discharge bridge 20 is provided with a gas inlet 21, but may be configured not to have a gas inlet 21. The gas inlet 21 is connected to a gas supply pipe 29 connected to a gas supply source (not shown). The gas inlet 21 and the first and second gas outlets 24a and 24b are respectively formed with flanges 22, 25a and 25b outward. The external discharge bridge 20 is composed entirely of non-conductor, for example, quartz.

The gas inlet 21 of the external discharge bridge 20 has a nozzle structure 26 inside the tube. As shown in FIG. 6 or FIG. 7, the inner diameter of the gas inlet 21 has structures 27a and 27b in which the upper and lower portions thereof are gradually increased / decreased about the nozzle structure 26. Alternatively, the inner diameter of the gas inlet 21 may have a structure in which the upper portion and the lower portion smoothly increase / decrease around the nozzle structure 26. The nozzle structure 26 is formed inside the gas inlet 21 to prevent the plasma from flowing back to the gas inlet 21 when the plasma is generated in the external discharge bridge 20.

3 to 5, the magnetic cores 30a and 30b are mounted on the external discharge bridges 20 so as to surround the first and second bridge lags 23a and 23b, respectively. The magnetic cores 30a and 30b are integrally mounted with a plurality of donut-shaped magnetic cores in the longitudinal direction of the first and second bridge lags 23a and 23b. The magnetic cores 30a and 30b have winding coils 31a and 31b connected to the power supply 32 to generate an electromotive force for exciting the plasma into the external discharge bridge 20 and the plasma reaction chamber 10. do. The power supply 32 supplies RF power to the first and second winding coils 31a and 31b. The winding coils 31a and 31b are connected in series to the power supply 32 but may be connected in parallel.

One end 33a of the first winding coil 31a wound on the first magnetic core 30a is connected to the power supply source 32 and the second winding coil 31b wound on the second magnetic core 30b. One end is connected to ground. The other end 33b of the first winding coil 31a and the other end 34b of the second winding coil 31b are electrically connected to each other. As such, the first and second winding coils 31a, 31b may be connected in series to the power source 32, or may be connected in parallel. In this case, the first and second winding coils 31a and 31b are wound to form a plasma discharge loop that extends into the external discharge bridge 20 and the plasma reaction chamber 10.

Cooling tubes 40a and 40b are provided between the external discharge bridge 20 and the magnetic cores 30a and 30b. The first cooling tube 40a is installed between the first bridge lag 23a and the first magnetic core 30a, and the second cooling tube (between the second bridge lag 23b and the second magnetic core 30b). 40b) is installed.

The first and second cooling tubes 40a and 40b are provided with cooling tube bodies 41a and 41b which surround the first and second bridge lags 23a and 23b in a cylindrical shape. Cooling water inlets 42a and 42b and cooling water outlets 43a and 43b are respectively provided at the upper portions of the cooling tube bodies 41a and 41b. In addition, at least one guide plate 44a, 44b is vertically installed on the inner ceiling of the cooling tube bodies 41a and 41b to guide the flow of the cooling water. The coolant flowing into the coolant inlets 42a and 42b proceeds between the induction diaphragms 44a and 44b and the cooling tube bodies 41a and 41b and is discharged to the coolant outlets 43a and 43b. The cooling tubes 40a and 40b prevent the external discharge bridge 20, the magnetic cores 30a and 30b and the upper surface 11 of the plasma reaction chamber 10 from overheating. The induction diaphragms 44a and 44b may be variously modified in shape or number in order to increase cooling efficiency.

The first and second cooling tubes 40a and 40b are made of a conductor. Although not shown in the drawing, an insulating wall is provided between the first and second cooling pipes 40a and 40b and the first and second magnetic cores 30a and 30b so that the first and the second cooling tubes 31a and 31b are separated from the winding coils 31a and 31b. 2 Prevent leakage of current into the cooling tubes 40a and 40b.

The first cooling tube 40a has a first ignition electrode 45a electrically connected thereto, and the second cooling tube 40b has a second ignition electrode 45b electrically connected thereto. The first ignition electrode 45a and the second ignition electrode 45b are disposed on the external discharge bridge 20 so as to face each other with the bridge body 25 therebetween. The first ignition electrode 45a is connected to the upper surface of the first cooling tube body 41a and is bent along the surface of the first bridge lag 23a to extend down to one side of the gas inlet 21. The second ignition electrode 45b is connected to the upper surface of the second cooling tube body 41b and is bent along the surface of the second bridge lag 23a to extend down to the opposite side of the gas inlet 21.

Since the first and second cooling tubes 40a and 40b are made of a conductor, when the induced electromotive force is generated by supplying power to the winding coils 31a and 31b of the first and second magnetic cores 30a and 30b. Induced electromotive force is also transmitted to the second cooling tubes 40a and 40b. However, the first and second magnetic cores 30a and 30b have winding coils 31a and 31b respectively installed so that induced electromotive force of opposite polarity is generated, so that the first cooling tube 40a and the second cooling tube 40b are provided. ) Are induced voltages of opposite polarity (+ V, -V) by the induced electromotive force of opposite polarities. Thus, a voltage difference is generated between the first and second ignition electrodes 45a and 45b to cause ignition for plasma discharge inside the external discharge bridge 20.

The first and second ignition electrodes 45a and 45b may be modified in various ways. For example, as shown in Figs. 8 and 9, the first and second ignition electrodes 45a and 45b form a flat end portion and are connected to the first and second cooling tube bodies 41a and 41b. Connect with wires 46a and 46b. The first ignition electrode 45a is installed close to the second cooling tube body 41b, and the second ignition electrode 45b is installed close to the first cooling tube body 41a.

Alternatively, as shown in FIGS. 10 and 11, the first and second ignition electrodes 45a and 45b are ring-shaped in the tubes of the first and second bridge lags 23a and 23b of the external discharge bridge 20. And connect the first and second cooling tube bodies 41a and 41b with wires 46a and 46b. At this time, the first ignition electrode 45a is provided close to the second cooling tube body 41b, and the second ignition electrode 45b is provided close to the first cooling tube body 41b.

As described above, when the structures and the mounting positions of the first and second ignition electrodes 45a and 45b are modified, the second ignition electrode 45b is formed between the first ignition electrode 45a and the second cooling tube 40b. ) And the first cooling tube 40a and between the first ignition electrode 45a and the second ignition electrode 45b respectively cause ignition for plasma discharge. In addition, the structures of the first and second ignition electrodes 45a and 45b may be modified in various forms.

12 is an overall cross-sectional view of the plasma processing chamber 10 of FIG. 1, and FIG. 13 is a perspective view of the diffusion inductor 19 of FIG. 12.

Referring to the drawings, the inner bottom of the plasma reaction chamber 10 is provided with a susceptor 14 on which the substrate 15 to be processed is placed. The substrate 15 to be processed may be a semiconductor wafer substrate, a glass substrate for LCD manufacture, or the like. The susceptor 14 is connected to the bias power supply 35 to receive the bias power supply. The lower end of the plasma reaction chamber 10 is provided with a gas outlet 16. A baffle plate 17 is installed across the inner upper region of the plasma reaction chamber 10. The baffle plate 17 is formed with a plurality of holes 18 therethrough.

A diffusion inductor 19 is provided between the baffle plate 17 and the ceiling of the plasma reaction chamber 10. The diffusion inductor 19 has an overall solid shape and an open top structure. The diffusion inductor 19 is preferably composed of a non-conductor, for example quartz. One or more holes 12a, 12b formed in the upper surface 11 of the plasma reaction chamber 10 are included in the open upper region of the diffusion inductor 19.

In the induction plasma source of the present invention as described above, the reaction gas is introduced into the plasma reaction chamber 10 through the external discharge tube bridge 20 in which the gas inlet 21 is installed. When RF power is supplied from the power supply source 32 to the winding coils 31a and 31b, an electromotive force for exciting the plasma into the external discharge bridge 20 and the plasma reaction chamber 10 is generated. In addition, induced electromotive force is also transmitted to the first and second cooling tubes 40a and 40b to generate a potential difference between the first and second ignition electrodes 45a and 45b, thereby causing ignition for plasma discharge. As a result, a continuous plasma discharge loop is generated into the external discharge bridge 20 and the plasma reaction chamber 10. The plasma gas is guided by the diffusion inductor 19 and passes evenly through the baffle plate 17 to the inner bottom of the plasma reaction chamber 10. At this time, the cooling water is supplied to the first and second cooling pipes 40a and 40b to prevent the external discharge bridge 20 and the upper surface 11 of the plasma discharge chamber 10 from being overheated, thereby preventing damage due to deterioration. prevent.

14 to 16 are a perspective view, a plan view of an external discharge bridge 20 in which the magnetic cores 30a and 30b and the cooling tubes 40a and 40b are mounted horizontally with the upper surface 11 of the plasma reaction chamber 10. And cross section.

As shown in the figure, the external discharge bridge 20 may be mounted horizontally on the upper surface 11 of the plasma discharge chamber 10, the magnetic core (30a, 30b) and the cooling tube (40a, 40b). The ignition electrodes 45a and 45b of the first and second cooling tubes 40a and 40b are installed in the inward direction facing each other, and the cooling water inlet and the outlet of the first and second cooling tubes 40a and 40b in the outer direction. 42a and 43a and 42b and 43a are provided.

17 and 18 are perspective views of the plasma processing chamber 10 equipped with a plurality of external discharge tube bridges 20-1, 20-2 and 20-3.

As shown in the figure, a plurality of external discharge tube bridges 20-1, 20-2, and 20-3 may be mounted in parallel on the upper surface 11 of the plasma processing chamber 10. The winding coils of the plurality of magnetic cores mounted on the plurality of external discharge tube bridges 20-1, 20-2, and 20-3 may be connected to the power supply 32 in any of a series, parallel or series / parallel combination. Can be. And the gas inlets of each of the external discharge tube bridges 20-1, 20-2, and 20-3 are interconnected by mutual gas connecting tubes (described below with reference to FIGS. 19 to 21) to be supplied from a gas source. Accept the reaction gas.

19 and 20 are perspective and cross-sectional views of the external discharge bridge 20 in which the gas connecting pipe 28 is provided at the gas inlet 21.

Referring to the drawings, the external discharge tube bridge 20 may be provided with a gas connecting pipe 28 at the gas inlet 21. The gas connecting pipe 28 has flange structures 28a and 28b at both ends thereof, and the center of the pipe is connected to the upper end of the gas inlet 21. And the inside of the gas inlet 21 has the nozzle structure 26 as mentioned above, and has the structure 27a, 27b which the upper part and the lower part increase / decrease gradually about it. The gas connecting pipe 28 may be installed in parallel with the first and second bridge lags 23a and 23b or may be installed in an orthogonal shape, as shown in FIG. 21. In the drawings, reference numerals 29a and 29b denote gas supply pipes connected to other gas connecting pipes or gas sources (not shown).

FIG. 22 is a perspective view of a plasma processing chamber having a cooling chamber on an upper surface of the plasma reaction chamber, and FIG. 23 is a view illustrating a coupling structure of the external discharge bridge and the plasma reaction chamber of FIG. 22.

Referring to the drawing, a cooling chamber 54 is provided at the center of the upper surface 11 of the plasma processing chamber 10. The cooling chamber 54 has a structure recessed downward from the upper surface 11 as a whole. Inside the cooling chamber 54, two holes 12a and 12b to which the external discharge bridge 20 is mounted are included.

24 and 25 are perspective and plan views of the external discharge bridge 20, and FIG. 26 is a cross-sectional view illustrating a structure in which the external discharge bridge 20 is coupled to the upper surface 11 of the plasma reaction chamber 10.

Referring to the drawings, the first and second gas outlets 24a, 24b of the first and second bridge lags 24a, 24b are respectively o-ringed in the two holes 12a, 12b of the upper surface 11, respectively. And vacuum insulated to 13a and 13b. The first and second gas outlets 24a and 24b have a common flange structure 50 that covers and seals the upper portion of the cooling chamber 54. The common flange 50 covers the upper part of the cooling chamber 54 by vacuum-insulating by the O-ring 53. The common flange 50 is provided with cooling water inlets / outlets 51a and 51b for inputting and outputting cooling water to the cooling chamber 54.

As such, since the cooling chamber 54 is provided on the upper surface 11 of the plasma reaction chamber 10, the external discharge bridge 20 and the upper surface 11 of the plasma reaction chamber 10 are overheated during the plasma reaction. It is possible to further prevent heat damage from occurring.

In this embodiment, although the common flange 50 of the first and second gas outlets 52a and 52b is used as the cover portion of the cooling chamber 54, a structure in which the cooling chamber 54 is covered and sealed separately may be adopted. There may be. 17 and 18, in the case where a plurality of external discharge bridges 20-1, 20-2, and 20-3 are installed on the upper surface 11 of the plasma reaction chamber 10, respectively, the cooling chambers. Will be able to come up. Cooling water inlets / outlets 51a and 51b of the cooling chamber 54 are configured in the common flange 50, but in another way, for example, the cooling chamber 54 at the upper surface 11 of the plasma reaction chamber 10. It may be configured a separate coolant inlet / outlet connected to the side of.

FIG. 27 is a cross-sectional view of the plasma processing chamber in which diffusion electrode pairs are provided in the plasma reaction chamber, and FIG. 28 is a cross-sectional view of FIG.

Referring to the drawings, the induction plasma source of the present invention further includes plasma diffusion means for inducing the acceleration paths P1 and P2 of the plasma ion particles 65 so that the plasma gas is uniformly diffused in the plasma reaction chamber 10. Include.

Plasma diffusion means are first electrode pairs (60a, 60b) having two plate electrodes disposed opposite to each other on the inner wall of the plasma reaction chamber 10, the inner wall of the plasma reaction chamber 10, Second electrode pairs 60c and 60d having two flat electrodes arranged orthogonally to the first electrode pairs 60a and 60b are provided. Respective electrodes of the first and second electrode pairs 60a and 60b and 60c and 60d are provided on the inner wall of the plasma reaction chamber 10 via insulators 61a, 61b, 61c and 61d.

The first electrode pair 60a, 60b is connected to a first power source 62 that supplies a first frequency, and the second electrode pair 60c, 60d is a second power source 63 that supplies a second frequency. Is connected to. The first and second frequencies may be the same or different frequencies. The frequency and voltage levels of the first and second power sources 62, 63 are controlled by the phase / voltage control unit 64.

29 is a flowchart of a power supply control procedure by the phase / voltage control unit, and FIGS. 30A to 30C are power supplies supplied to the first and second electrode pairs 60a, 60b, 60c, and 60d according to the whole power supply control procedure. Is a waveform diagram of.

Referring to the figure, the phase / voltage control unit 64 controls the first and second power sources 63 and 64 to control the frequency and phase of the output power. In step S10, the first and second frequencies are initialized to have a first phase difference and a first voltage level. For example, as shown in FIG. 30A, the first and second power sources 62 and 63 may have a phase difference of 180 degrees and have a first voltage level (+ Vpp, -Vpp). ). In step S12, the start frequency is controlled to be output to the first and second electrode pairs 60a and 60b (60c and 60d).

Subsequently, in step S14, the first and second frequencies are controlled to have a second phase difference and to have a second voltage level. For example, as shown in FIG. 30B, the first and second frequencies have a phase difference of 90 degrees and are stabilized to have second voltage levels (+ Vpp ', -Vpp'). In step S16, the first and second frequencies having the second phase difference and the second voltage level are output to the first and second electrode pairs 60a and 60b and 60c and 60d at a stable frequency.

In this embodiment, the phase / voltage controller 64 controls both the frequency and voltage levels of the first and second power sources 62, 63, but as shown in FIG. 30C, the frequency is not adjusted without adjusting the voltage level. Can only be adjusted.

When power is supplied from the first and second power sources 62 and 63 to the first and second electrode pairs 60a, 60b, 60c, 60d, respectively, the first and second electrode pairs 60a, 60b, 60c. , Between the electric fields E1 and E2 perpendicular to each other. Acceleration in which the plasma ion particles 65 rotate by two electric fields E1 and E2 that intersect vertically when the frequency phases of the first and second power sources 62 and 36 are controlled by the phase / voltage control unit 64. Will have paths 66a and 66b. Thus, the plasma ion particles 65 are evenly dispersed in the plasma reaction chamber 10.

Although the configuration and operation of the induction plasma source having an external discharge bridge according to a preferred embodiment of the present invention as described above are shown according to the above description and drawings, this is merely an example and the technical spirit of the present invention. Those skilled in the art will appreciate that various changes and modifications can be made without departing from the scope of the invention.

According to the present invention as described above, the heat discharge is prevented from occurring in the external discharge bridge and the plasma reaction chamber by the cooling tube provided in the external discharge bridge and the cooling chamber provided in the upper surface of the plasma reaction chamber. By configuring the ignition electrode by using a cooling tube installed in the external discharge bridge, it is not necessary to have a separate ignition electrode and the ignition power can increase the efficiency of equipment configuration. A high density uniform and wide volume of plasma can be obtained inside the plasma reaction chamber by providing a plasma diffusion means having a diffusion inductor, a baffle plate and a plurality of electrode pairs inside the plasma reaction chamber.

Claims (26)

A plasma reaction chamber having at least two holes in an upper surface thereof and having a susceptor in which a workpiece to be processed is placed; At least one external discharge bridge positioned outside the plasma reaction chamber and coupled to the at least two holes; A power supply for supplying RF power; At least one magnetic core mounted to surround an external discharge bridge, the magnetic core having an external discharge bridge and a winding coil connected to a power supply source for generating an electromotive force for exciting plasma into the plasma reaction chamber; An inductively coupled plasma source comprising at least one cooling tube disposed between an external discharge bridge and a magnetic core. 2. The inductively coupled plasma source of claim 1 wherein the external discharge bridge is comprised of a non-conductor. 2. The apparatus of claim 1, wherein the external discharge bridge comprises: a C-shaped hollow bridge body having a first bridge lag connected to one hole of the plasma reaction chamber and a second bridge lag connected to the other hole; A gas inlet protruding from the upper center portion of the bridge body to receive reaction gas supplied from a gas source; And An inductively coupled plasma source having first and second gas outlets inserted into the two holes as respective ends of first and second bridge lags. 4. The inductively coupled plasma source of claim 3 wherein the gas inlet and the first and second gas outlets have a flange structure. 4. The inductively coupled plasma source of claim 3, wherein the gas inlet comprises a nozzle structure and a structure in which the inner diameter is increased / decreased smoothly or gradually increased / decreased. 4. The inductively coupled plasma source as recited in claim 3, wherein the external discharge bridge further comprises a gas connection tube connected to a center of the tube at an upper end of the gas inlet and allowing a reactive gas supplied from the gas source to be provided to the gas inlet. The inductively coupled plasma source of claim 6, wherein both ends of the gas connection pipe and the first and second gas outlets have a flange structure. According to claim 1, wherein the cooling tube is a cooling tube body surrounding the external discharge bridge; A coolant inlet and a coolant outlet connected to the cooling tube body; An inductively coupled plasma source comprising at least one induction diaphragm installed inside the cooling tube body to guide the flow of cooling water from the cooling water inlet to the cooling water outlet. 2. The apparatus of claim 1, wherein the external discharge bridge comprises: a first bridge lag connected to one hole of the plasma reaction chamber; Has a C-shaped hollow bridge body with a second bridge lag connected to another hole, The magnetic core may include a first magnetic core installed in the first bridge lag; A second magnetic core installed in the second bridge lag, The cooling tube may include a first cooling tube installed between the first bridge lag and the first magnetic core; An inductively coupled plasma source having a second cooling conduit disposed between a second bridge lag and a second magnetic core. 10. The method of claim 9, wherein the first cooling tube and the second cooling tube is composed of a conductor, the first cooling tube is a first ignition electrode electrically connected to the second ignition tube is electrically connected to the second ignition Further comprising electrodes, each of the first and second ignition electrodes disposed on the external discharge bridge; Each of the first and second magnetic cores has winding coils installed so that induced electromotive force of opposite polarity is generated, and the induced voltage of opposite polarity is generated by the induced electromotive force of opposite polarity of the first cooling tube and the second cooling tube. Wherein the first and second ignition electrodes cause ignition for plasma discharge. The inductively coupled plasma source of claim 10, wherein the first and second ignition electrodes extend from the first and second cooling tubes and are disposed to face each other with an external discharge bridge interposed therebetween. The method of claim 10, wherein the first and second ignition electrodes are coupled to the tube of the external discharge bridge in a ring shape, wherein the first ignition electrode is installed close to the second cooling tube and the second ignition electrode is connected to the first cooling tube. Closely inductively coupled plasma source. 10. The inductively coupled plasma source as recited in claim 9, wherein said external discharge bridge has a gas inlet protruding from a top central portion of the bridge body to receive a reactive gas supplied from a gas source. The inductively coupled plasma source of claim 1 wherein the plasma reaction chamber comprises a baffle plate disposed across an inner top region and having a plurality of holes therethrough. 15. The method of claim 14, wherein the overall shape and the top is open, is installed between the inner ceiling and the baffle plate of the plasma reaction chamber to induce the plasma gas to enter through the external discharge bridge evenly diffused into the inner lower portion of the plasma reaction chamber An inductively coupled plasma source comprising a diffusion inductor. The inductively coupled plasma source of claim 1 comprising a bias power supply for supplying bias power to the susceptor. The inductively coupled plasma source of claim 1, wherein the plasma reaction chamber comprises a cooling chamber formed on an outer upper surface to include at least two holes. 18. The apparatus of claim 17, wherein the external discharge bridge comprises: a C-shaped hollow bridge body having a first bridge lag connected to one hole of the plasma reaction chamber and a second bridge lag connected to the other hole; Each end of the first and second bridge lags having first and second gas outlets respectively connected to the two holes, An inductively coupled plasma source having a common flange structure in which first and second gas outlets cover and seal an upper portion of the cooling chamber. The cooling system of claim 17, wherein the cooling chamber comprises: first and second o-rings installed between the common flange and the two holes; An inductively coupled plasma source comprising a third o-ring disposed between the common flange and the plasma reaction chamber. 18. The inductively coupled plasma source of claim 17, wherein the cooling chamber comprises a coolant inlet and a coolant outlet formed on a common flange. 21. The inductively coupled plasma source as recited in claim 20, wherein said external discharge bridge includes a gas inlet that protrudes from a top central portion of the bridge body to receive a reactive gas supplied from a gas source. The inductively coupled plasma source of claim 1, further comprising plasma diffusion means for inducing an acceleration path of the plasma ion particles to uniformly diffuse the plasma gas within the plasma reaction chamber. The method of claim 22, wherein the plasma diffusion means is: A first electrode pair having two plate electrodes disposed to face each other on an inner wall of the plasma reaction chamber; A second electrode pair having two plate electrodes disposed to face each other on an inner side wall of the plasma reaction chamber and disposed to be orthogonal to the first electrode pair; A first power supply for supplying a first frequency to the first electrode pair; A second power supply source supplying a second frequency to the second electrode pair; And a phase / voltage control unit for controlling the first and second power sources to control phase and voltage of the first and second frequencies. 24. The inductively coupled plasma source of claim 23, wherein each of the electrodes of the first and second electrode pairs is installed through an insulator on an inner wall of the plasma reaction chamber. 24. The method of claim 23 wherein the control of the first and second power sources of the phase / voltage control is: Initializing the first and second frequencies to have a first phase difference; Outputting first and second frequencies having a first phase difference as a starting frequency; Controlling the phase such that the first and second frequencies have a second phase difference; And And outputting a first and a second frequency having a second phase difference at a stable frequency. 27. The inductively coupled plasma source of claim 25 further comprising changing a voltage level from a first voltage level to a second voltage level when a stable frequency is output.

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