KR100935144B1 - Plasma processing apparatus - Google Patents

Abstract

An object of this invention is to provide the plasma processing apparatus of the simple structure which can process the to-be-processed surface of a workpiece | work in a short time.

As a means for solving the said subject, the plasma processing apparatus 1 of this invention has the workpiece installation which installs the 1st electrode 2 which has the hollow part 40 which penetrated from the upper end to the lower end, and the workpiece | work 10. The outer peripheral side of the opening part 422 of the lower end side of the hollow part 40 and the 2nd electrode 3 arrange | positioned facing the lower end of the 1st electrode 2 via the part 100, the workpiece | work installation part 100, and the hollow part 40. FIG. A power supply circuit 7 including a processing gas ejection part 5 formed in the circumferential direction, a power supply 72 for applying a voltage between the first electrode 2 and the second electrode 3, and a processing gas. It is provided with the gas supply means 8 which supplies the process gas for plasma generation to the blowing part 5, and applies a voltage between the 1st electrode 2 and the 2nd electrode 3, 5), the processing gas present in the vicinity of the opening 422 is activated to generate a plasma, and the plasma to treat the target surface 101 of the workpiece 10 by the plasma. It is configured to handle rasmas.

1st electrode, 2nd electrode, a workpiece | work, a workpiece | work installation part, a processing gas blowing part, a power supply circuit, a gas supply means, the to-be-processed surface of a workpiece | work, a plasma processing apparatus

Description

Plasma processing unit {PLASMA PROCESSING APPARATUS}

The present invention relates to a plasma processing apparatus.

When processing the surface of the material, the processing is performed by supplying a reaction gas to an electrode to which a voltage or high frequency is applied, generating a radical based on the reaction gas, and removing a product generated by the radical reaction of the radical and the work. So-called Plasma Chemical Vaporization Machining (hereinafter abbreviated as "plasma CVM") is performed.

In recent years, in the so-called etching process using active species such as radicals excited by plasma, it is important to increase the radical density to improve the processing speed.

In order to cope with this, the plasma processing apparatus using the roll electrode which can generate a high density radical is known (for example, patent document 1). Moreover, the plasma processing apparatus using a hollow cathode discharge electrode is known (for example, patent document 2).

On the other hand, with the recent increase in the processing area, there has been a demand for a plasma processing apparatus having a simple structure that can cope with work of various sizes.

In order to cope with this, in the conventional plasma processing apparatus, the method of processing while changing a positional relationship with each other, such as scanning an electrode or a workpiece, is used.

However, with the said plasma processing apparatus, the processing efficiency of a workpiece | work, a processing speed, etc. are inadequate, and the apparatus itself cannot be said to be a simple structure.

(Patent Document 1) Japanese Unexamined Patent Application Publication No. 2001-120988

(Patent Document 2) Japanese Unexamined Patent Application Publication No. 2001-35692

(Patent Document 3) Japanese Unexamined Patent Publication No. 1-125829

SUMMARY OF THE INVENTION An object of the present invention is to provide a plasma processing apparatus having a simple structure that can process a target surface of a workpiece in a short time.

This object is achieved by the following invention.

The plasma processing apparatus of the present invention includes a first electrode having a hollow portion penetrating from an upper end to a lower end,

Work installation department to install work,

A second electrode disposed opposite the lower end of the first electrode via the work mounting portion;

A processing gas ejection part formed along the circumferential direction on an outer circumferential side of the lower end opening of the hollow part;

A power supply circuit having a power supply for applying a voltage between the first electrode and the second electrode;

A gas supply means for supplying a process gas for plasma generation to the process gas ejection part,

By applying a voltage between the first electrode and the second electrode, the processing gas is blown out of the processing gas ejection unit to activate the processing gas present in the vicinity of the lower end side opening to generate a plasma, and the plasma causes the workpiece to work. And a plasma treatment of the surface to be treated.

Thereby, since plasma concentrates in the immediate vicinity of the opening of the lower end side of the hollow part which penetrated, the efficiency of plasma processing to the to-be-processed surface of a workpiece | work can be raised.

In the plasma processing apparatus of this invention, it is preferable that the said process gas blown off from the said plasma injection part comprises the flow of the direction toward the said lower end opening, and the flow of the direction separated from the said lower end opening.

As a result, the processing gas easily gathers in the immediate vicinity of the lower end opening, so that the plasma density increases, and the surface to be processed can be efficiently processed in a short time.

In the plasma processing apparatus of this invention, it is preferable that the flow of a process gas is formed in the said hollow part in the direction toward the upper end side from the said lower end opening.

Thereby, since the reaction product which generate | occur | produced by the plasma process flows to the upper end side of a hollow part, plasma processing efficiency does not fall.

In the plasma processing apparatus of this invention, it is preferable that the said process gas blowing part is formed intermittently along the circumferential direction in the outer peripheral side of the said lower end opening.

As a result, the processing gas flows efficiently near the lower end opening, so that the gas pressure in the immediate vicinity of the lower end opening can be increased with a small amount of gas.

In the plasma processing apparatus of this invention, it is preferable that the said process gas blowing part is annularly formed over the perimeter around the said lower end opening.

Thereby, since there is more process gas and uniformly flows in the immediate vicinity of the lower end opening, the gas pressure in the immediate vicinity of the lower end opening becomes higher, and a high density plasma can be generated.

In the plasma processing apparatus of this invention, it is preferable that the said process gas ejection part is comprised so that the ejecting direction of the process gas ejected from it may incline toward the extension line of the line segment which connects the said upper end and said lower end of the said hollow part.

Thereby, since a process gas flows reliably toward the extension line of a line segment, the gas pressure of the immediate vicinity of a lower end opening is high, and high density plasma can be generated.

In the plasma processing apparatus of this invention, it is preferable to provide the gas exhaust means which exhausts the process gas ejected from the said process gas ejection part from the upper end of the said hollow part of the said 1st electrode.

As a result, since the reaction product generated by the plasma treatment can be reliably exhausted, the efficiency of the plasma treatment does not decrease.

Moreover, since dust (electrode material etc.) which arises from abnormal discharge between electrodes or between an electrode and a workpiece can also be exhausted and removed, the efficiency of plasma processing does not fall.

In the plasma processing apparatus of this invention, it is preferable that the said gas exhaust means has exhaust flow volume adjustment means which adjusts the exhaust flow volume of the process gas exhausted from the upper part of the said hollow part.

As a result, the process gas can be set to an appropriate exhaust flow rate, so that the reaction product can be reliably exhausted while the plasma is maintained immediately below the lower end opening.

In addition, since the processing shape tends to be disturbed by the ejection of the processing gas, the processing shape (processing trace) can be controlled by intermittently controlling (adjusting) the exhaust timing and adjusting the gas pressure under the first electrode.

Further, the processing speed (processing rate) can be controlled by intermittently controlling (adjusting) the exhaust timing and controlling the stay time of radicals in the (high) plasma generation region.

In the plasma processing apparatus of the present invention, the exhaust flow rate adjusting means includes: a discharge pipe connected to an upper end of the hollow portion;

A valve for opening and closing the flow path in the discharge pipe,

It is preferable to include a pump provided downstream of the discharge pipe via the valve.

Thereby, since the exhaust flow volume of a process gas can be set reliably, the reaction product can be reliably exhausted, maintaining plasma in the immediate vicinity of the lower end opening.

In the plasma processing apparatus of this invention, it is preferable to provide cooling means for cooling the said 1st electrode.

Thereby, since the 1st electrode which generate | occur | produced by discharge can be cooled, high density plasma can be produced stably.

In addition, since the heat generation of the first electrode can be suppressed by reducing the hole diameter of the first electrode, the influence of heat generated by the discharge on the work can be suppressed.

In the plasma processing apparatus of the present invention, it is preferable that at least a surface side of the first electrode facing the second electrode is covered with a dielectric part.

Thereby, since a metal etc. which are electrodes are not exposed between a pair of electrodes, an arc discharge can be prevented and an electric field can be generated uniformly.

In the plasma processing apparatus of this invention, it is preferable that the said process gas blowing part is formed in the dielectric part.

Thereby, since the metal etc. which are electrodes are not exposed between a 1st electrode and a 2nd electrode, an electric field is generated uniformly and a glow-like discharge can be obtained.

In the plasma processing apparatus of the present invention, the outer diameter of the dielectric portion is larger than the outer diameter of the first electrode.

As a result, the processing gas flows without turbulence in the direction away from the direction toward the lower end opening of the hollow portion, so that the flow of the processing gas can be controlled.

In the plasma processing apparatus of this invention, it is preferable to provide a plurality of said 1st electrodes.

Thereby, the process suited to the to-be-processed surface of a workpiece | work can be performed.

Best Mode for Carrying Out the Invention

EMBODIMENT OF THE INVENTION Hereinafter, the plasma processing apparatus of this invention is demonstrated in detail based on suitable embodiment shown to an accompanying drawing.

<1st embodiment>

1 is a longitudinal sectional view showing a schematic configuration of a first embodiment of a plasma processing apparatus of the present invention, FIG. 2 is a cross-sectional view taken along the line A-A in FIG. 1, and FIG. 3 is a bottom view of the dielectric portion.

In addition, in the following description, the upper side in FIG. 1 is called "upper | on", and lower side is called "lower | bottom".

As shown in FIG. 1, the plasma processing apparatus 1 includes a first electrode 2 having a hollow portion 40 penetrating from an upper end to a lower end, a work attaching part 100 for installing the work 10, and , The second electrode 3 disposed to face the lower end of the first electrode 2 via the work mounting portion 100, the dielectric portion 4 accommodating the first electrode 2, and the hollow portion 40. The process gas ejection part 5 formed in the outer peripheral side of the opening part 422 of the lower end side along the circumferential direction, and the process gas which guides the process gas supplied from the gas supply means 8 to the process gas ejection part 5 Plasma generation in the power supply circuit 7 having the supply flow path 6, the power supply 72 for applying a voltage between the first electrode 2 and the second electrode 3, and the processing gas ejection part 5. Gas supply means (8) for supplying a process gas for supplying; and exhaust means (9) for exhausting the process gas ejected from the process gas ejection part (5) from the upper end of the hollow part (40); have.

The plasma processing apparatus 1 is ejected from the processing gas ejection section 5 by applying a voltage between the first electrode 2 and the second electrode 3, and immediately near the opening 422 at the lower end side. A plasma is generated by activating a processing gas present in the apparatus, and processing the target surface 101 of the workpiece 10 by the plasma.

In this embodiment, the case where an etching process or a dicing process is performed by plasma is demonstrated.

Hereinafter, the structure of each part of the plasma processing apparatus 1 is demonstrated.

The 1st electrode 2 is arrange | positioned facing the workpiece | work 10 provided in the workpiece | work installation part 100. As shown in FIG. The first electrode 2 is a cylindrical electrode (so-called hollow cathode electrode) having a hollow portion 40 penetrating from the upper end face center portion 21 to the lower end face center portion 22.

Since the first electrode has the hollow portion 40, a so-called electron trapping effect occurs in which electrons generated by the discharge in the hollow portion 40 collide with the inner wall of the first electrode 2. And a part of the electrons, or a part of the secondary electrons generated when the ions of the gas ionized by the electrons collide with the electrode, is located near the opening 422 immediately below the opening 422 from the lower end side (hereinafter, It jumps out to the "high density plasma generation area | region 301." Therefore, the density of the electrons of the hollow part 40 and the high density plasma generation area | region 301 improves. As a result, the electric field strength increases in the hollow portion 40 and the high density plasma generating region 301. By the supply of the processing gas, the high density plasma is generated in the hollow portion 40 and the high density plasma generating region 301, and the target surface 101 of the work 10 can be efficiently processed.

This hollow part 40 has the upper end opening 401 which opens to the upper end surface of the 1st electrode 2, and the lower end opening 402 which opens to the lower end surface of the 1st electrode 2. As shown in FIG. The upper end opening 401 communicates with the gas exhaust means 9 described later. The lower end opening 402 communicates with the lower end opening (hereinafter abbreviated as "opening") 422.

In addition, the cross-sectional shape of the hollow part 40 is not specifically limited, Round shape, elliptical shape, square shape, etc. are mentioned.

The first electrode 2 is housed in a substantially cylindrical dielectric portion 4 having an upper surface 411 and having a recessed portion 412 (in FIG. 1 except for the upper end of the first electrode 2). part).

In this way, since the first electrode 2 is accommodated in the dielectric portion 4, the metal or the like, which is an electrode, is not exposed between the first electrode 2 and the second electrode 3. The electric field can be generated uniformly in the inside.

In addition, an increase in impedance can be prevented, and a desired discharge can be generated at a relatively low voltage, so that plasma can be surely generated.

It is also possible to prevent breakdown at the time of voltage application, to suitably prevent the occurrence of arc discharge, and to obtain a glow-like stable discharge.

This dielectric part 4 has a main body 41 having a recess 412, and an enlarged diameter part (flange part) 42 having an outer diameter is formed on the lower surface side of the main body 41.

Since the outer diameter of the enlarged diameter part 42 is larger than the main body 41, the disturbance of gas flow can be prevented and the flow of a process gas can be smoothly controlled.

The main body 41 is provided with the process gas supply flow path 6 mentioned later in the circumferential direction on the outer peripheral side of the recessed part 412. As shown in FIG.

In addition, the shape of the main body 41 is not specifically limited, for example, a cylindrical shape, a truncated cone, and a square shape.

As shown in FIG. 3, the lower surface 421 of the enlarged diameter portion 42 has a reaction product generated by plasma treatment at the center thereof between the first electrode 2 and the second electrode 3 (hereinafter, “ An opening (lower end side opening of the hollow portion 40) 422 is exhausted from the plasma generating region 30 &quot;.

Thus, the opening part 422 is provided in the lower surface 421 of the enlarged diameter part 42, and since the process gas containing the reaction product generate | occur | produced by the plasma process can be exhausted from the plasma generation area | region 30, the reaction product The fall of the processing speed by remaining in this plasma generation area | region 30 can be prevented.

In addition, since the opening 422 is provided in the lower surface 421, the processing gas flows from the opening 422 to the upper end of the hollow portion 40, so that the reaction product adheres to the surface to be processed 101 of the workpiece 10. Can be prevented.

In addition, since the high-density plasma generating region 301 has a high plasma density and is easy to collect the reaction product at the center, the opening 422 is provided at the center of the lower surface 421, so that the reaction product can be exhausted efficiently.

As shown in FIG. 3, the process gas blowing part 5 is formed in the lower surface 421 of the enlarged diameter part 42 intermittently along the circumferential direction on the outer peripheral side of the opening part 422. As shown in FIG. And the process gas blowing part 5 is located in the lower surface 421 of the enlarged diameter part 42, and is located so that it may face the workpiece | work 10 side.

In this way, the processing gas ejection part 5 is formed intermittently along the circumferential direction on the outer circumferential side of the opening portion 422, and the processing gas flows efficiently through the plasma generating area 30, so that the plasma generating area is reduced with a smaller amount of gas. The gas pressure of 30 can be raised.

In addition, the process gas which flowed in the direction toward the extension line (henceforth simply called "the line segment 20") of the line segment which connects the upper end and the lower end of the hollow part 40 from the plasma ejection part 5 to the line segment 20 Each collides and flows away from the line segment 20. Therefore, since the time which the process gas activated (ionization, ionization, excitation, etc.) exists in the plasma generation area | region 30 becomes long, a process rate improves.

In addition, the cross-sectional shape of the process gas blowing part 5 is not specifically limited, for example, circular shape, strip | belt-shaped.

This process gas blowing part communicates with the process gas supply flow path 6 which extends and installs in the main body 41 of the dielectric part 4, and is installed.

The processing gas supply flow passage 6 branches off the introduction passage 61 on the gas supply means 8 side that introduces the processing gas into the processing gas ejection section 5 and the introduction passage 61 to process the processing gas. The branch flow path 62 which leads to the gas blowing part 5 and the toroidal flow path 63 which guides the process gas from the introduction path 61 to the branch flow path 62 are provided.

The annular flow passage 63 is formed in an annular portion in the middle portion of the main body 41 of the dielectric portion 4. One end of the introduction passage 61 extending in the vertical direction inside the main body 41 communicates with the annular flow passage 63.

The other end of the introduction passage 61 is opened on the upper surface 411 of the main body 41 and communicates with the processing gas pipe 84 of the gas supply means 8. In the present embodiment, two introduction paths 61 are provided at positions facing the main body 41 via the first electrode 2.

In addition, one end of the branch flow passage 62 extending in the vertical direction is in communication with the toroidal flow passage 63. The other end of this branch flow path 62 communicates with the processing gas ejection part 5. In the present embodiment, as shown in Figs. 1 and 2, eight branch flow passages 62 are arranged at equal intervals from the annular flow passage 63.

In addition, the cross-sectional shape of the introduction path 61, the branch flow path 62, and the annular flow path 63 is not specifically limited, for example, circular shape, a strip | belt shape, etc., respectively.

Since the process gas supply flow path 6 has such a structure, rather than introducing a process gas to the process gas ejection part 5 in one introduction path 61, the introduction path 61 (branch flow path 62). The flow path resistance of the processing gas flowing through the?) Can be reduced, and the processing gas can be efficiently distributed to the branch flow path 62.

As a constituent material of the dielectric part 4 mentioned above, various plastics, such as polytetrafluoroethylene and polyethylene terephthalate, various glass, such as quartz glass, an inorganic oxide, etc. are mentioned, for example. Examples of the inorganic oxide include dielectric materials such as metal oxides such as Al ₂ O ₃ (alumina), SiO ₂ , ZrO ₂ , TiO ₂ , nitrides such as silicon nitride, and composite oxides such as BaTiO ₃ (barium titanate). Etc. can be mentioned. Among these, a metal oxide is preferable and alumina is more preferable. By using such a material, generation | occurrence | production of the arc discharge in an electric field can be prevented more reliably.

The upper end of the first electrode 2 is exposed from the dielectric portion 4. And since this 1st electrode 2 is an electrode for applying a voltage, it is connected to the power supply 72 via the conducting wire 71 in order to make electrical connection in the exposed position.

Although it does not specifically limit as a constituent material of the 1st electrode 2, For example, metals, such as copper, aluminum, iron, silver, various alloys, such as stainless steel, brass, an aluminum alloy, intermetallic compound, various carbons Materials, and the like.

In addition, the shape of the 1st electrode 2 will not be specifically limited if it is a shape which has a hollow part, For example, cylindrical shape, a columnar shape, etc. are mentioned.

The 2nd electrode 3 is arrange | positioned facing the 1st electrode 2 via the workpiece | work 10 provided in the workpiece | work installation part 100, and is directly grounded via the conducting wire 71. FIG. And since the 2nd electrode 3 also has a function as the workpiece installation part 100, the workpiece | work 10 is provided in contact with the upper surface (work installation part 100) of the 2nd electrode 3, and is provided.

The constituent material of the second electrode 3 may be the same material as that of the first electrode 2, and is not particularly limited. In addition, the shape of the 2nd electrode 3 can also mention the shape similar to the 1st electrode 2, and is not specifically limited.

The power supply circuit 7 includes a high frequency power source 72 for applying a voltage between the first electrode 2 and the second electrode 3, and a second electrode 3, a high frequency power source 72, and a first electrode ( The conducting wire 71 which conducts 2) is provided. Although not shown in the figure, a matching circuit (impedance matching circuit) for power to be supplied, a frequency adjusting means (circuit) for changing the frequency of the high frequency power source 72, and a maximum value of the applied voltage of the high frequency power source 72 are shown. Voltage adjusting means (circuit) for changing the (amplitude) is provided as necessary. Thereby, the processing conditions of the plasma processing with respect to the workpiece | work 10 can be adjusted suitably.

A high frequency power supply (power supply unit) 72 is connected to the first electrode 2 via a conducting wire (cable) 71, and a high frequency power supply (via a conducting wire 71) to the second electrode 3. 72 is connected, and the power supply circuit 7 is comprised by this. A part of this power supply circuit 7, that is, the conductive wire 71 on the second electrode 3 side is earthed (grounded).

When the plasma processing is performed on the work 10, the high frequency power supply 72 operates to apply a voltage between the first electrode 2 and the second electrode 3. At this time, an electric field is generated between the hollow portion 40 of the first electrode 2 and between the first electrode 2 and the second electrode 3, when gas is supplied, a discharge occurs, and the plasma Occurs.

Moreover, although the frequency of the high frequency power supply 72 is not specifically limited, It is preferable that it is 10-70 MHz, and it is more preferable that it is 10-40 MHz.

The gas supply means 8 supplies the process gas for plasma generation to the process gas supply flow path 6. The gas supply means 8 includes a gas cylinder (gas supply source) 81 for filling and supplying a predetermined gas, and a mass flow controller (flow rate adjusting means) for adjusting the flow rate of the gas supplied from the gas cylinder 81. 82, a valve (flow path opening and closing means) 83 for opening and closing the flow path in the processing gas pipe 84 on the downstream end side of the mass flow controller 82, and the processing gas pipe connected to the processing gas supply flow path 6 ( 84).

Such gas supply means 8 sends out predetermined gas from the gas cylinder 81, and adjusts the flow volume with the mass flow controller 82. FIG. Then, the processing gas is introduced (supplied) into the processing gas ejection section 5 from the introduction passage 61 opening to the upper surface 411 of the main body 41 of the dielectric section 4 via the processing gas pipe 84. do.

Various gases can be used for the gas (process gas) used for such a plasma process according to a process objective. For the purpose of etching or dicing as in the present embodiment, for example, fluorine atom-containing compounds such as CF ₄ , C ₂ F ₆ , C ₃ F ₆ , C ₄ F ₈ , CClF ₃ , SF _6, etc. different halogen-based gases, such as gas or Cl _2, BCl _3, CCl _4, such as a chlorine atom-containing compound gas may be used.

In addition, in the case of other processing purposes, the processing gas as shown below can be used according to the objective.

(a) If for the purpose of heating the front and rear surfaces features 101 of the work 10 can be used, for example, the N _2, O ₂ or the like.

(b) In order to make water-repellent (water-repellent) the to-be-processed surface 101 of the workpiece | work 10, the said fluorine atom containing compound gas can be used, for example.

(c) For the purpose of making the surface 101 of the workpiece 10 hydrophilic (lyophilic), for example, oxygen atoms containing compounds such as O ₃ , H ₂ O, air, N ₂ , NH ₃ compounds containing nitrogen atoms, such as, can be used a compound containing a sulfur atom, such as SO _2, SO _3. Thereby, hydrophilic functional groups, such as a carbonyl group, a hydroxyl group, and an amino group, are formed in the to-be-processed surface 101 of the workpiece | work 10, surface energy can be made high, and a hydrophilic surface can be obtained. Moreover, a hydrophilic polymer film can also be deposited (formed) using the polymerizable monomer which has hydrophilic groups, such as acrylic acid and methacrylic acid.

(d) In order to add electrical and optical functions to the target surface 101 of the workpiece 10, a metal oxide thin film such as SiO ₂ , TiO ₂ , SnO _2, or the like may be applied to the target surface 101 of the workpiece 10. ), Metal-hydrogen compounds of metals such as Si, Ti, Sn, metal-halogen compounds, metal alkoxides (organic metal compounds) and the like can be used.

(e) For the purpose of resist treatment or removal of organic contamination, an oxygen-based gas can be used, for example.

As such a process gas, generally, the mixed gas (henceforth simply called "gas") which consists of the said process gas and carrier gas can be used. In addition, "carrier gas" means the gas introduce | transduced for discharge start and discharge maintenance.

In this case, the mixed gas (process gas + carrier gas) may be filled and used in the gas cylinder 81, and the process gas and the carrier gas are respectively filled in different gas cylinders, and these are carried out in the middle of the process gas pipe 84. The configuration may be mixed at a predetermined mixing ratio.

As the carrier gas, rare gases such as He, Ne, Ar, and Xe can be used. These can be used individually or in the form which mixed 2 or more types.

The ratio (mixing ratio) of the processing gas in the mixed gas is slightly different depending on the purpose of the treatment, and is not particularly limited. For example, the ratio of the processing gas in the mixed gas is preferably 1 to 10%, and is preferably 5 to It is more preferable that it is 10%. Thereby, discharge is started efficiently and a desired plasma process can be performed with a process gas.

The flow rate of the gas to be supplied is appropriately determined according to the kind of gas, the purpose of the treatment, the degree of the treatment, and the like. Usually, it is preferable that it is about 30 SCCM-50 SLM. Thereby, since the pressure of the plasma generation area | region 30 rises efficiently, a fine process can be performed.

The gas exhaust means 9 exhausts and recovers the plasma, the reaction product, the inert processing gas, etc. generated in the plasma generating region 30 from the upper end opening 401 of the hollow portion 40.

This gas exhaust means 9 is provided on the downstream end side of the exhaust flow rate adjusting means 90 for adjusting the exhaust flow rate of the processing gas exhausted from the upper end surface opening portion 401 of the hollow portion 40 and the discharge pipe 91. It has decontamination facilities 95, such as a PFC decontamination apparatus and a scrubber.

The exhaust flow rate adjusting means 90 includes a discharge pipe 91 connected to the upper end surface opening portion 401 of the hollow portion 40, a valve (flow path opening and closing means) 92 for opening and closing the flow path in the discharge pipe 91, and And a mass flow controller 93 for adjusting the flow rate of the gas discharged by the pump 94, and a pump 94 provided downstream of the discharge pipe 91 via the valve 92.

The gas exhaust means 9 opens the valve 92 and operates the pump 94 to put the hollow portion 40 temporarily in a reduced pressure state. Next, the gas exhaust means 9 operates the mass flow controller 93 to adjust the exhaust flow rate. And the gas exhaust means 9 exhausts the process gas containing a reaction product or plasma from the upper surface opening part 401 to the discharge pipe 91, and exhausts it from the removal installation 95 to the outside.

The process gas ejected from the process gas ejection part 5 flows in two directions, a flow in the direction toward the line segment 20 and a flow in the direction away from the line segment 20. The processing gas flowing toward the line segment 20 reaches the line segment 20 (high density plasma generating region 301), and the pressure of the processing gas increases. At this time, since the pump 94 of the gas exhaust means 9 operates to temporarily depressurize the inside of the discharge pipe 91, the pressure difference between the high-density plasma generation region 301 and the discharge pipe 91 causes the processing gas to be removed. It flows from the high density plasma generating region 301 to the opening 422. Then, a flow of processing gas is formed from the lower end opening 402 of the hollow part 40 toward the upper end opening 401 of the hollow part 40. As a result, the processing gas is exhausted from the upper end opening 401 to the discharge pipe 91.

Thus, since the plasma processing apparatus 1 is equipped with the gas exhaust means 9, since the gas exhaust means 9 can accelerate the exhaust flow volume, it is possible to reliably exhaust the reaction product generated by the plasma treatment.

In addition, since the gas exhaust means 9 can adjust the exhaust flow rate of the processing gas, the high-density plasma can be kept in the high-density plasma generating region 301. As a result, the to-be-processed surface 101 of the workpiece | work 10 can be processed in a short time, without reducing a processing rate.

In addition, since the flow of the processing gas from the opening portion 422 to the top surface opening portion 401 of the hollow portion 40 is surely formed, the new processing gas can be efficiently supplied to the high density plasma generating region 301.

In addition, since the processing gas flows from the lower end side to the upper end side of the hollow portion 40, the gas exhaust means 9 is foreign matter derived from the first electrode 2 caused by the discharge of the first electrode 2 (electrode material). Dust or the like) and foreign matters generated by abnormal discharge in the plasma generating region 30 can also be exhausted. As a result, contamination of the to-be-processed surface 101 by the foreign material can be prevented, and the fall of plasma processing efficiency can be prevented.

In addition, since the processing shape is likely to be disturbed by the ejection of the processing gas from the plasma spraying unit 5, the processing is performed by intermittently controlling (adjusting) the exhaust timing and adjusting the gas pressure under the first electrode 2. The shape (process mark) can be controlled.

In addition, the processing speed can be controlled by intermittently controlling (adjusting) the exhaust timing and controlling the staying time of radicals in the plasma generating region 301.

In addition, even when there is no gas exhaust means 9, as in the fourth embodiment described later, the pressure of the high-density plasma generating region 301 is increased, so that it is hollowed out from the opening 422 by the pressure difference with the atmosphere. A natural flow of processing gas towards the top surface opening 401 of the portion 40 is formed.

Although it does not specifically limit as the workpiece | work 10, In this embodiment, what can be used for the board | substrate of an electronic device is mentioned, for example. Specific materials include, for example, various glass such as quartz glass, alkali free glass, quartz, various ceramic materials such as alumina, silica, titania, various semiconductor materials such as silicon, gallium arsenide, polyethylene, polypropylene, polystyrene, poly The thing comprised from dielectric materials, such as various plastics (resin material), such as a carbonate, polyethylene terephthalate, polytetrafluoroethylene, a polyimide, a liquid crystal polymer, a phenol resin, an epoxy resin, an acrylic resin, is mentioned. Among these, it can use suitably especially for various glass, such as quartz and quartz, and various semiconductor materials. As a shape of the workpiece | work 10, a plate-shaped thing, a long layer shape thing, etc. are mentioned.

[2] operating methods

Next, the operation (operation) of the processing apparatus 1 will be described.

The work 10 is provided in the center (work installation part 100) of the 2nd electrode 3. As shown in FIG. The power supply circuit 7 is operated, and the valve 83 is opened. Then, the mass flow controller 82 adjusts the flow rate of the gas, and supplies the gas from the gas cylinder 81. As a result, the gas supplied from the gas cylinder 81 flows into the processing gas pipe 84 and is introduced into the introduction path 61. The processing gas introduced into the introduction passage 61 flows downward, and flows through the annular flow passage 63 in the middle of the main body 41. And the process gas which flows through the torus flow path 63 flows in the branch flow path 62 below, and is ejected from the process gas blowing part 5.

Although the process gas ejected from the process gas ejection part 5 is ejected directly below immediately after ejection, when it hits the workpiece | work 10 directly under the process gas ejection part 5, a part is a direction which goes to the line segment 20. In the (high-density plasma generation region 301 direction), a part is divided into a direction (outer circumferential direction) separated from the line segment 20. Then, the processing gas is collected in the high density plasma generating region 301, and the gas pressure increases.

On the other hand, by the operation of the power supply circuit 7, a high frequency voltage is applied between the first electrode 2 and the second electrode 3 to generate an electric field in the plasma generating region 30 and the hollow portion 40. .

At this time, the electrons generated in the hollow portion 40 repeatedly collide with the inner wall of the hollow portion 40, and the ionization efficiency is promoted. Then, a part of the electrons or a part of the secondary electrons generated by the collision of the ions of the gas ionized by the electrons with the electrode protrudes from the opening 422 into the high density plasma generating region 301. As a result, the electric field strength increases in the hollow portion 40 and the high density plasma generating region 301.

In addition, since the density of the processing gas decreases toward the outer circumference of the high density plasma generating region 301, the glow discharge is in a glow discharge state.

The processing gas introduced into the plasma generating region 30 is activated by discharge, and plasma is generated.

And the generated plasma (activated gas) contacts the to-be-processed surface 101 of the workpiece | work 10, and the to-be-processed surface 101 is processed (etching, dicing, etc.).

In the high-density plasma generating region 301, since the gas pressure increases, the reaction product generated by the unreacted process gas, plasma or plasma treatment due to the pressure difference between the high-density plasma generating region 301 and the discharge pipe 91. The processing gas including the flows toward the opening 422. Those processing gases which flowed toward the opening portion 422 flow from the opening portion 422 to the bottom surface opening portion 402. The process gas flows from the lower end opening 402 to the upper end opening 401 through the hollow portion 40.

At this time, the pump 94 is operated and the valve 92 is opened. Then, the mass flow controller 93 adjusts the exhaust flow rate of the gas. As a result, the processing gas is sucked in, and the processing gas flows through the discharge pipe 91 connected to the upper end opening 401 and is exhausted from the removal facility 95 to the outside. In addition, the reaction product is exhausted from the decontamination facility 95 to the outside, or recovered to the decontamination facility 95.

In such a plasma processing apparatus 1, the first electrode 2 is moved in the x-axis direction and the y-axis direction by a moving means (not shown) with respect to the workpiece 10 provided on the second electrode 3. In doing so, the desired position on the work 10 is subjected to plasma treatment.

For example, after the plasma is generated, the first electrode 2 is scanned in the y-axis plus direction of the surface to be processed 101, and then a predetermined pitch (for example, the outer diameter of the first electrode 2) is scanned. Minutes) and move in the y-axis minus direction. Such scanning (moving) may be repeated sequentially and the whole surface of the to-be-processed surface 101 of the workpiece | work 10 may be processed.

In the scanning method of the first electrode 2 described above, when the plasma is moved in a predetermined pitch minute x-axis direction, plasma generation is stopped once and then moved in the predetermined pitch minute x-axis direction, and then the plasma is again displayed. You may generate | occur | produce and process it.

By the above operation | movement, the to-be-processed surface 101 of the workpiece | work 10 can be processed efficiently regardless of the magnitude | size of the workpiece | work 10. As shown in FIG.

In addition, instead of moving the first electrode 2, the second electrode 3 (work mounting portion 100) or the work 10 provided with the work 10 is moved with the first electrode 2 described above. You may move it similarly.

The processing apparatus 1 described above includes a crystal oscillator processing, drilling of a sensor substrate, grooving electrode formation (solar cell, filter, laminated substrate), de-smearing processing of a printed substrate, HDD Electronic component fields such as pattern processing of members, deburring of IC resin mold packages, drilling of device wafers, semiconductor related fields such as grooving of ceramic wafers, FPD related fields such as conductive film peeling partition formation, etc. It can be applied to processing of an insulating film, removal, torsion removal processing such as glass (quartz), crystal processing, and the like. Moreover, application to MEMS etc. is also possible. Further, by using a photoresist mask, fine patterning is also possible.

<2nd embodiment>

Fig. 4 is a bottom view of the dielectric part showing the schematic configuration of the second embodiment of the plasma processing apparatus of the present invention.

Hereinafter, the plasma processing apparatus of 2nd Embodiment is demonstrated centering on difference with 1st Embodiment mentioned above, and the description is abbreviate | omitted about the same matter.

The plasma processing apparatus 1 of this embodiment differs from the first embodiment in that the processing gas ejection portion 5 is annularly formed over the entire circumference in the circumferential direction on the outer peripheral side of the opening portion 422. Do. Therefore, the whole circumference of the toroidal flow path 63 extends downward as it is, and becomes the branched flow path 62 so as to communicate with the process gas ejection part 5. Thus, since the process gas ejection part 5 is annularly arranged over the entire circumference in the circumferential direction on the outer circumferential side of the opening portion 422, the process gas flows more uniformly in the high density plasma generating region 301, thereby providing a high density. The gas pressure in the plasma generating region 301 is higher, which can generate high density plasma.

In addition, since the branch flow passage 62 forms an annular flow passage, the resistance of the processing gas flowing through the branch flow passage 62 can be made smaller than in the case of the first embodiment.

Third Embodiment

5 is a longitudinal sectional view showing a schematic configuration of a third embodiment of a processing apparatus of the present invention.

In addition, in the following description, the upper side in FIG. 5 is called "upper | on", and lower side is called "lower | bottom".

Hereinafter, the processing apparatus of the third embodiment will be described focusing on the difference from the above-described first embodiment, and the description thereof will be omitted.

The plasma processing apparatus 1 of this embodiment differs from the plasma processing apparatus 1 of 1st Embodiment in the following points.

The process gas ejection part (nozzle) 5 formed in the lower surface 421 of the enlarged diameter part 42 is inclined toward the high density plasma generation region 301.

In this way, since the nozzle 5 is inclined in the direction toward the high density plasma generating region 301, the sprayed processing gas is surely flowed to the high density plasma generating region 301, and thus the processing gas is discharged by the enclosing effect of the processing gas. You can focus more. As a result, the gas pressure in the high-density plasma generation region 301 is increased, and high-density plasma can be generated.

The recessed part 424 which forms the lower surface 421 as the bottom surface 423 is formed in the lower surface 421 of the enlarged diameter part 42 of the inner peripheral side rather than the nozzle 5.

Further, an annular annular flow passage 63 is formed at the lower end of the main body 41 of the dielectric portion 4. One end of the introduction passage 61 communicates with the annular flow passage 63. The other end of the introduction passage 61 is opened to the lower end side surface 413 of the main body 41 and communicates with the processing gas pipe 84 of the gas supply means 8.

Moreover, one end of the branch flow path 62 which extends the main body 41 in the up-down direction communicates with the toroidal flow path 63. The other end of the branch flow path 62 communicates with the nozzle 5 inclined toward the high density plasma generation region 301. The nozzle 5 is opened to the side surface of the recess 424. In this embodiment, eight nozzles 5 are intermittently formed in the side surface of the recessed part 424.

In addition, the nozzle 5 may be formed annularly over the perimeter around the opening part 422. In this case, the nozzle 5 is formed in the shape of a truncated cone.

Although the inclination angle with respect to the line segment 20 of the nozzle 5 is not specifically limited, For example, it can be made into about 0.5-40 degrees. In addition, the inclination-angle of the nozzle 5 can change suitably in the range of 0 (same as 1st Embodiment)-40 degrees (for example, the structure which uses a movable nozzle, a diameter-expansion part ( 42) may be configured as a detachable material (replaceable) with respect to the main body 41).

<4th embodiment>

The plasma processing apparatus of the fourth embodiment will be described focusing on the difference from the above-described third embodiment, and the description thereof will be omitted.

The plasma processing apparatus 1 of this embodiment is the same as that of 1st embodiment except not having the gas exhaust means 9.

Since the plasma processing apparatus 1 of this embodiment does not include the gas exhaust means 9, the apparatus structure of the plasma processing apparatus 1 can be made simple. Moreover, since the plasma processing apparatus 1 does not have the gas exhaust means 9, the installation space of the plasma processing apparatus 1 can be reduced.

In addition, since the plasma processing apparatus 1 of this embodiment does not include the gas exhaust means 9, the operation | movement of processing gas differs from 3rd Embodiment.

That is, the process gas ejected from the process gas ejection part 5 flows in two directions, a flow in the direction toward the line segment 20 and a flow in the direction apart from the line segment 20. The processing gas flowing toward the line segment 20 reaches the vicinity of the line segment 20 (high-density plasma generating region 301), and the pressure of the processing gas increases. At this time, a process gas flows from the high density plasma generation area 301 to the opening part 422 by the pressure difference between the high density plasma generation area 301 and the discharge pipe 91. Then, a natural flow of processing gas from the lower end opening 402 of the hollow part 40 toward the upper end opening 401 of the hollow part 40 is formed. As a result, the processing gas is exhausted from the upper end opening 401.

In addition, the plasma processing apparatus 1 of this embodiment may provide an exhaust pipe for exhausting the exhausted processing gas to a predetermined place.

<Fifth Embodiment>

6 is a longitudinal sectional view showing a schematic configuration of a fifth embodiment of the plasma processing apparatus of the present invention. Hereinafter, the plasma processing apparatus of 5th Embodiment is demonstrated centering on difference with 1st Embodiment mentioned above, and the description is abbreviate | omitted about the same matter.

The plasma processing apparatus 1 of this embodiment is the same as that of 1st embodiment except that the cooling means 50 is provided.

The cooling means 50 stores a coolant from a coolant tank 501 for storing and supplying a coolant, a coolant pipe 502, a coolant jacket 503 connected to the coolant pipe 502, and a coolant jacket 503. A refrigerant discharge pipe 504 for discharging and a refrigerant recovery tank 505 for recovering the refrigerant are included.

The coolant tank 501 stores a coolant used for cooling the first electrode 2.

As such a refrigerant | coolant, various refrigerants can be used. Typically water can be used. For example, a replacement flon refrigerant, an inorganic compound refrigerant such as ammonia or carbon dioxide, or an organic compound refrigerant such as isobutane may be used. You may use these refrigerants in combination of 2 or more type.

The coolant jacket 503 is provided in contact with the outer circumferential surface of the first electrode 2 in the main body 41 of the dielectric portion 4. The refrigerant jacket 503 is formed in a spiral shape so as to surround the first electrode 2.

Thus, since the coolant jacket 503 is provided in contact with the outer circumferential surface of the first electrode 2, the first electrode 2 can be cooled reliably.

One end of the coolant jacket 503 opens in the upper surface 411 of the main body 41 and communicates with the coolant pipe 502. On the other hand, the other end side of the refrigerant jacket 503 communicates with the refrigerant discharge pipe 504 extending in the up-down direction in the main body 41 on the outer circumferential side of the spiral refrigerant jacket 503.

By providing such cooling means 50, since the temperature of the 1st electrode 2 which generate | occur | produced by discharge can be kept constant, plasma can be produced stably. As a result, the to-be-processed surface 101 of the workpiece | work 10 can be processed with fixed processing efficiency.

Next, an example of the operation | movement of the cooling means 50 is demonstrated.

Before operating the power supply circuit 7, the coolant is sent from the coolant tank 501 to the coolant pipe 502. The refrigerant sent to the refrigerant pipe 502 flows into the refrigerant jacket 503 at a predetermined flow rate and is recovered to the refrigerant recovery tank through the refrigerant discharge pipe 504. The recovered refrigerant can be used as a refrigerant again.

At this time, the refrigerant is exchanged with the first electrode 2 while the refrigerant flows through the refrigerant jacket 503 to cool the first electrode 2.

In addition, the coolant jacket 503 may be provided in the 1st electrode 2 by the structure similar to the above.

In addition, the cooling means 50 may be the hollow part 40 which made the internal diameter small. By reducing the inner diameter of the hollow portion 40, it is possible to suppress the heat generation of the first electrode 2 due to the discharge, so that the heat generated by the discharge adversely affects the target surface 101 of the workpiece 10. Can be prevented and suppressed.

Sixth Embodiment

FIG. 7: is a longitudinal cross-sectional view which shows schematic structure of 6th Embodiment of the plasma processing apparatus of this invention.

In addition, in the following description, the upper side in FIG. 7 is called "upper | on", and lower side is called "lower | bottom".

Hereinafter, the processing apparatus of the sixth embodiment will be described focusing on the difference from the above-described first embodiment, and the description thereof will be omitted.

In the plasma processing apparatus 1 of this embodiment, three 1st electrodes 2 accommodated in the dielectric part 4 are connected in parallel, and the process gas supply flow path 6 between 1st electrodes 2 comrades is carried out. It is the same as that of 1st Embodiment except having mutually used.

In the plasma processing apparatus 1 of the present embodiment, as shown in FIG. 7, the first electrode 2 is connected to the power source 72 through the conductive wire 71 in order to obtain respective electrical connections.

Moreover, the discharge pipe 91 of the gas exhaust means 9 branches, and is connected to the upper end surface opening part 401, respectively.

In addition, the process gas pipe 84 of a gas supply means is branched, and is connected to the introduction path 61, respectively.

In addition, the 1st electrode 2 may be comprised so that attachment and detachment are each possible. Accordingly, it is possible to cope with all kinds of work 10.

In this way, since the plasma processing apparatus 1 includes a plurality of the first electrodes 2, the plasma generating regions 30 are formed by the number of the first electrodes 2, so that the surface to be processed of the workpiece 10 is extremely fast. 101 can be processed.

Moreover, since the 1st electrode 2 is provided in multiple numbers, it can respond also to the workpiece | work 10 of all kinds, for example, the workpiece | work 10 with a large area.

As mentioned above, although the plasma processing apparatus of this invention was demonstrated based on each embodiment shown in drawing, this invention is not limited to these. Each part which comprises a plasma processing apparatus can be substituted with the thing of arbitrary structures which can exhibit the same function. Moreover, arbitrary structures may be added.

In addition, the plasma processing apparatus of this invention may combine arbitrary 2 or more structures (characteristics) among the said each embodiment. For example, combining the configurations of the first embodiment and the fourth embodiment, combining the configurations of the third embodiment and the fifth embodiment, and combining the configurations of the fourth embodiment and the sixth embodiment. It may be a thing.

In addition, the moving means for moving a 2nd electrode is not specifically limited, For example, various moving mechanisms are mentioned.

The high frequency power supply may be a direct current as long as it is the same potential.

As mentioned above, this invention can be used to provide the plasma processing apparatus of the simple structure which can process the to-be-processed surface of a workpiece | work in a short time.

BRIEF DESCRIPTION OF THE DRAWINGS The longitudinal cross-sectional view which shows schematic structure of 1st Embodiment of the plasma processing apparatus of this invention.

FIG. 2 is a cross-sectional view taken along the line A-A in FIG. 1. FIG.

3 is a bottom view of the dielectric part in FIG.

Fig. 4 is a bottom view of the dielectric portion showing the second embodiment of the plasma processing apparatus of the present invention.

5 is a longitudinal sectional view showing a schematic configuration of a third embodiment of a plasma processing apparatus of the present invention.

6 is a longitudinal sectional view showing a schematic configuration of a fifth embodiment of the plasma processing apparatus of the present invention.

The longitudinal cross-sectional view which shows schematic structure of 6th Embodiment of the plasma processing apparatus of this invention.

[Description of the code]

DESCRIPTION OF SYMBOLS 1 Plasma processing apparatus 2: 1st electrode 21: Top surface center part

22: lower surface center 3: second electrode 4: dielectric portion 41: main body 411: upper surface

412: recess 413: lower end side 42: enlarged diameter 421: lower surface 422: opening

423: Bottom 424: Concave portion 5: Process gas ejecting unit 6: Process gas supply flow path

61: introduction route 62: branching flow path 63: torus flow path 7: power supply circuit 71: lead wire

72: power source 8: gas supply means 81: gas cylinder 82: mass flow controller

83: valve 84: process gas pipe 9: gas exhaust means 91: discharge pipe 92: valve

93: mass flow controller 94: pump 95: removal equipment 10: work

101: to-be-processed surface 20: line segment 30: plasma generation area

301: high-density plasma generation region 40: hollow portion 401: top surface opening

402: lower end opening 50: cooling means 501: refrigerant tank 502: refrigerant pipe

503: refrigerant jacket 504: refrigerant discharge pipe 505: refrigerant recovery tank

90: exhaust flow rate adjusting means 100: work mounting portion

Claims (18)

A cylindrical first electrode having a hollow portion penetrating from an upper end to a lower end, Work installation department to install work, A second electrode disposed opposite the lower end of the first electrode via the work mounting portion; A concave portion formed by an inner cylinder surface and a bottom surface parallel to the lower surface of the first electrode, an opening provided in the bottom surface of the recess portion, in communication with a lower end of the hollow portion, and the inner cylinder surface of the inner cylinder surface. A process gas ejection part which is provided in the circumferential direction and in which the ejection direction of the process gas ejected is inclined toward an extension line of the line segment connecting the upper end of the hollow portion and the lower end of the opening, and the annular process gas communicating with the process gas ejection part; A first hole portion constituting the flow path and a second hole portion constituting the processing gas introduction path communicating with the annular processing gas flow path, and the center of the inner diameter of the recess and the center of the outer diameter of the first electrode are the line segments. Or a dielectric part positioned on an extension line of the line segment and having an inner diameter of the concave portion smaller than an outer diameter of the first electrode, covering the first electrode; A power supply circuit having a power supply for applying a voltage between the first electrode and the second electrode; A process gas supply means for supplying a process gas for plasma generation from said second gas hole to said process gas ejection part, By applying a voltage between the first electrode and the second electrode, the treatment gas is blown out of the processing gas ejection unit to activate the processing gas present in the vicinity of the opening to generate a plasma, and the plasma features the workpiece. Plasma processing apparatus characterized in that it is configured to plasma process the surface. The method of claim 1, The processing gas ejected from the processing gas ejection part constitutes a flow in a direction toward the lower end opening and a flow in a direction apart from the lower end opening. The method according to claim 1 or 2, And a flow of processing gas is formed in the hollow portion in a direction from the lower end opening toward the upper end. The method of claim 1, The said processing gas blowing part is formed in the outer peripheral side of the said lower end opening intermittently along the circumferential direction. delete delete The method of claim 1, And a gas exhaust means for exhausting the process gas ejected from the process gas ejection part from the upper end of the hollow part of the first electrode. The method of claim 7, wherein And said gas exhaust means comprises exhaust flow rate adjusting means for adjusting the exhaust flow rate of the processing gas exhausted from the upper end of said hollow part. The method of claim 8, The exhaust flow rate adjusting means includes a discharge pipe connected to an upper end of the hollow portion, A valve for opening and closing the flow path in the discharge pipe, And a pump provided on the downstream side of the discharge pipe via the valve. The method of claim 1, And a coolant jacket provided in the dielectric portion in contact with an outer side surface of the first electrode. The method of claim 1, The said 1st electrode is the plasma processing apparatus by which the surface side facing at least the said 2nd electrode is covered by the dielectric part. delete delete delete The method of claim 11, And said dielectric portion has a concave portion with an open upper surface, and said first electrode is accommodated in said concave portion. The method of claim 11, The processing gas ejecting portion is formed in the dielectric portion. The method according to claim 15 or 16, The said dielectric part is a plasma processing apparatus whose outer diameter is diameter diameter larger than the outer diameter of the said 1st electrode. The method of claim 1, A plasma processing apparatus comprising a plurality of the first electrodes.

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