JP2020123446A - Plasma processing apparatus - Google Patents

Abstract

To efficiently supply a high frequency magnetic field which is generated from an antenna, to a processing chamber in a plasma processing apparatus in which the antenna is disposed outside of the processing chamber.SOLUTION: The present invention relates to a plasma processing apparatus which processes an object to be processed by using plasma. The plasma processing apparatus comprises: a vacuum chamber 2 forming a processing chamber 1 of which the inside is evacuated and in which a gas is introduced; and an antenna 3 which is disposed outside of the processing chamber 1 and connected to a high frequency power source 4 and generates a high frequency magnetic field. In the plasma processing apparatus, the vacuum chamber 2 includes a magnetic field permeation window 5 through which the high frequency magnetic field generated from the antenna 3 is permeated into the processing chamber 1, and the magnetic field permeation window 5 is constituted of a metal rolled sheet.SELECTED DRAWING: Figure 2

Description

The present invention relates to a plasma processing apparatus that processes an object to be processed using plasma.

Conventionally, there is a plasma processing apparatus in which a high-frequency current is passed through an antenna, an inductively-coupled plasma (abbreviated as ICP) is generated by an inductive electric field generated by the high-frequency current, and the inductively-coupled plasma is used to process a workpiece such as a substrate. Has been proposed by. As such a plasma processing apparatus, in Patent Document 1, an antenna is arranged outside a vacuum container, and a high frequency magnetic field generated from the antenna is transmitted into the vacuum container through a dielectric window provided in an opening of a side wall of the vacuum container. Therefore, a device for generating plasma in the processing chamber is disclosed.

JP, 2017-004665, A

However, in the above-described plasma processing apparatus, since the dielectric window is used as a part of the side wall of the vacuum container, the dielectric window has sufficient strength to withstand the pressure difference between the inside and outside of the vacuum container when the inside of the vacuum container is evacuated. Must have In particular, since the dielectric material forming the dielectric window is ceramics or glass having low toughness, it is necessary to increase the thickness of the dielectric window in order to have sufficient strength to withstand the above-mentioned differential pressure. Therefore, since the distance from the antenna to the processing chamber in the vacuum container becomes long, the induced electric field in the processing chamber becomes weak and the efficiency of plasma generation decreases.

The present invention has been made in view of such a problem, and provides a plasma processing apparatus in which an antenna is arranged outside a processing chamber and a high-frequency magnetic field generated from the antenna can be efficiently supplied to the processing chamber. The main task is to do.

The present inventors have conducted extensive studies to solve the above problems, and have focused on a metal material that has been conventionally considered to be unsuitable as a constituent material of a magnetic field transmission window that transmits a high frequency magnetic field generated from an antenna. After further intensive studies, it was found that by rolling a metal material into a sheet shape, this can be used as a magnetic field transmission window for transmitting a magnetic field. Furthermore, if the metal material has a higher toughness than the dielectric materials such as ceramics and glass that are conventionally used as the constituent material of the magnetic field transmission window, even if the thickness is reduced, the pressure difference between the inside and outside of the processing chamber is They have found that they can withstand the strength, and have reached the present invention.

That is, the plasma processing apparatus according to the present invention processes an object to be processed using plasma, and is provided outside the processing chamber and a vacuum container that forms a processing chamber that is evacuated and into which a gas is introduced. The vacuum container has a magnetic field transmission window for transmitting the high frequency magnetic field generated from the antenna into the processing chamber, and the magnetic field transmission window, It is characterized in that it is composed of a rolled metal sheet.

With such a structure, since the magnetic field transmission window is made of a metal material, the magnetic field transmission window of the magnetic field transmission window is larger than that of a case where the magnetic field transmission window is made of a dielectric material such as ceramics having a lower toughness than the metal material. The thickness can be reduced. Therefore, the distance from the antenna to the processing chamber can be reduced, and the high frequency magnetic field generated from the antenna can be efficiently supplied into the processing chamber.
Further, by forming the magnetic field transmitting window with a metal material, all the members of the vacuum container surrounding the processing chamber, which is a plasma generation space, can be electrically grounded. Therefore, the influence of the voltage of the antenna on the plasma can be reduced, and the electron temperature and the ion energy can be reduced.
The "rolled metal sheet" in the present invention is a sheet formed by rolling a metal (at least 1 mm or less), and does not include, for example, a metal thin film formed by vacuum treatment.

In the plasma processing apparatus, the vacuum container includes a container body and a window member that is attached to the container body and forms the magnetic field transmission window, and the window member includes the metal rolling sheet and the metal rolling sheet. It is preferable to have a holding frame for holding the sheet.
In such a case, since the window member forming the magnetic field transmission window is a member separate from the container body, even if the rolled metal sheet is consumed due to corrosion due to gas, deterioration due to heat, etc. The rolled metal sheet can be easily replaced and cleaned.

The rolled metal sheet is preferably adhered to the holding frame with an adhesive.
With this configuration, it is possible to reliably seal the space between the holding frame and the rolled metal sheet, and to reliably prevent the rolled metal sheet from falling off during vacuum processing. Further, compared to the case where a gasket such as an O-ring is used, the contact area between the holding frame and the rolled metal sheet can be increased, and the heat generated in the rolled metal sheet can be easily released to the holding frame.

It is preferable that the rolled metal sheet is thermally connected to the holding frame and the container body.
In such a case, if the holding frame and the container body are configured to be cooled by, for example, water cooling or air cooling, the heat generated in the rolled metal sheet is released to the holding frame and the container body, and the magnetic field transmission window is opened. Can be cooled. Therefore, it is possible to suppress the temperature rise of the object to be processed due to the radiant heat from the magnetic field transmission window, and to perform the plasma processing on the object to be processed more stably.

It is preferable that the plasma processing apparatus further includes a support beam that supports the rolled metal sheet from the side of the processing chamber.
With such a structure, even if the rolled metal sheet is evacuated to the processing chamber and is bent toward the treatment chamber, the rolled metal sheet is supported by the support beam, so that the rolled metal sheet can be prevented from being damaged. it can. Further, if the support beam is configured to be cooled by air cooling or water cooling, the magnetic field transmission window can be cooled by releasing the heat generated in the rolled metal sheet to the support beam. Therefore, it is possible to further suppress the temperature rise of the object to be processed due to the radiant heat from the magnetic field transmission window, and to perform the plasma processing on the object to be processed more stably.

If the thickness of the rolled metal sheet is larger than the skin thickness at the frequency of the high-frequency current flowing through the antenna, the high-frequency magnetic field generated from the antenna may not be able to be transmitted into the processing chamber through the magnetic field transmission window. Therefore, it is preferable that the thickness of the rolled metal sheet be equal to or less than the skin thickness at the frequency of the high frequency current flowing through the antenna.
With such a structure, the high frequency magnetic field generated from the antenna can be more stably supplied to the processing chamber.

The thickness of the rolled metal sheet is preferably 100 μm or less, more preferably 90 μm or less, from the viewpoint of efficiently supplying the high-frequency magnetic field to the processing chamber. On the other hand, the thickness of the rolled metal sheet is preferably 20 μm or more, and more preferably 30 μm or more, from the viewpoint of ensuring the strength capable of withstanding the differential pressure inside and outside the processing chamber during vacuum processing.

As a specific embodiment of the rolled metal sheet, one metal selected from the group containing Cu, Al, Zn, Ni, Sn, Si, Ti, Fe, Cr, Nb, C, Mo, W or Co, or Mention may be made of those alloys.

According to the present invention thus configured, it is possible to provide a plasma processing apparatus in which the antenna is arranged outside the processing chamber, and the high-frequency magnetic field generated from the antenna can be efficiently supplied to the processing chamber.

It is sectional drawing orthogonal to the longitudinal direction of the antenna which shows typically the whole structure of the plasma processing apparatus of this embodiment. FIG. 3 is a cross-sectional view along the longitudinal direction of the antenna, which schematically shows the overall configuration of the plasma processing apparatus of the same embodiment. FIG. 3 is a cross-sectional view along the longitudinal direction of the antenna, which schematically shows the configuration of the window member of the plasma processing apparatus of the same embodiment. It is the top view seen from the antenna side which shows typically the composition of the window member of the plasma processing apparatus of the embodiment. It is a top view which shows typically the structure of the window member of the plasma processing apparatus of other embodiment. It is sectional drawing along the longitudinal direction of the antenna which shows typically the structure of the window member of the plasma processing apparatus of other embodiment. It is a top view which shows typically the structure of the window member of the plasma processing apparatus of other embodiment. It is sectional drawing along the longitudinal direction of the antenna which shows typically the structure of the window member of the plasma processing apparatus of other embodiment. 6 is a graph showing the relationship between the high frequency power applied to the antenna and the plasma emission intensity of Ar.

A plasma processing apparatus according to an embodiment of the present invention will be described below with reference to the drawings. Note that the plasma processing apparatus described below is for embodying the technical idea of the present invention, and the present invention is not limited to the following unless specified otherwise. Further, the contents described in one embodiment can be applied to other embodiments. In addition, the sizes and positional relationships of the members shown in the drawings may be exaggerated for clarity.

<Device configuration>
The plasma processing apparatus 100 according to the present embodiment uses an inductively coupled plasma P to process an object to be processed such as a substrate. Here, the substrate is, for example, a substrate for a flat panel display (FPD) such as a liquid crystal display or an organic EL display, a flexible substrate for a flexible display, or the like. The processing performed on the substrate is, for example, film formation by plasma CVD, etching, ashing, sputtering, or the like.

The plasma processing apparatus 100 of the present embodiment is a plasma CVD apparatus when forming a film by a plasma CVD method, a plasma etching apparatus when performing etching, a plasma ashing apparatus when performing ashing, and a plasma when performing sputtering. Also called a sputtering device.

Specifically, as shown in FIG. 1, the plasma processing apparatus 100 includes a vacuum chamber 2 that forms a processing chamber 1 that is evacuated and into which a gas G is introduced; an antenna 3 that is provided outside the processing chamber 1; The antenna 3 is provided with a high frequency power source 4 for applying a high frequency. The vacuum container 2 is provided with a magnetic field transmission window 5 for transmitting a high frequency magnetic field generated from the antenna 3 into the processing chamber 1. As a result, when a high frequency is applied to the antenna 3 from the high frequency power source 4, the high frequency magnetic field generated from the antenna 3 is transmitted through the magnetic field transmission window 5 and is formed in the processing chamber 1, so that the high frequency magnetic field is guided to the space inside the processing chamber 1. An electric field is generated, which causes inductively coupled plasma P to be generated.

The vacuum container 2 includes a container body 21 and a window member 22 that forms the magnetic field transmission window 5. The container body 21 is, for example, a metal container, and is electrically grounded in this example. An opening 212 is formed on a side wall (here, the upper side wall 21a) of the container body 21, and the window member 22 is detachably attached to the container body 21 so as to close the opening 212. In this way, the processing chamber 1 is formed by the inner wall of the container body 21 and the window member 22. The window member 22 and the container body 21 are vacuum-sealed with a gasket such as an O-ring.

The vacuum chamber 2 is configured such that the processing chamber 1 is evacuated by the vacuum exhaust device 6. The vacuum container 2 is configured such that the gas G is introduced into the processing chamber 1 via, for example, a flow rate regulator (not shown) and a plurality of gas introduction ports 211 provided in the container body 21. The gas G may be selected according to the processing content applied to the substrate. For example, when the film is formed on the substrate by the plasma CVD method, the gas G is a raw material gas or a gas obtained by diluting it with a diluent gas (for example, H ₂ ). More specifically, a Si film is used when the source gas is SiH _4, a SiN film is used when SiH ₄ +NH _3, a SiO ₂ film is used when SiH ₄ +O ₂ , and a SiN film is used when SiF ₄ +N _2. : F film (fluorinated silicon nitride film) can be formed on each substrate.

A substrate holder 7 for holding a substrate is provided inside the vacuum container 2. As in this example, the bias voltage may be applied to the substrate holder 7 from the bias power supply 8. The bias voltage is, for example, a negative DC voltage, a negative bias voltage, or the like, but is not limited to this. With such a bias voltage, for example, the energy when the positive ions in the plasma P enter the substrate can be controlled, and the crystallinity of the film formed on the surface of the substrate can be controlled. A heater 71 for heating the substrate may be provided in the substrate holder 7.

As shown in FIGS. 1 and 2, a plurality of antennas 3 are provided, and each antenna 3 is arranged outside the processing chamber 1 so as to face the magnetic field transmission window 5, and is connected to the magnetic field transmission window 5. The distance between them is about 2 mm. Each antenna 3 is arranged along the surface of the substrate provided in the processing chamber 1 (for example, substantially parallel to the surface of the substrate). The antennas 3 have the same configuration, are linear, and have a length of several tens of cm or more. A high-frequency power source 4 is connected to a power feeding end which is one end 3a of the antenna 3 through a matching circuit 41, and a terminal 3b which is the other end is directly grounded. The terminal portion 3b may be grounded via a capacitor or a coil.

With the above configuration, the high frequency current IR can be passed from the high frequency power supply 4 to the antenna 3 via the matching circuit 41. The high frequency is, for example, a general 13.56 MHz, but is not limited to this.

Here, each antenna 3 has a hollow structure having a flow passage through which a cooling liquid flows. Specifically, as shown in FIG. 2, each antenna 3 includes at least two tubular conductor elements 31 made of metal, and a capacitor 32 which is a quantitative element electrically connected in series with the conductor elements 31 adjacent to each other. Equipped with. Here, the number of conductor elements 31 included in one antenna 3 is three, and the number of capacitors 32 is two. Each conductor element 31 has a straight tubular shape in which a linear flow path through which the cooling liquid flows is formed, and the material thereof is, for example, copper, aluminum, an alloy thereof, stainless steel, or the like. It is not limited to.

By configuring each antenna 3 in this way, the combined reactance of the antenna 3 is simply the inductive reactance minus the capacitive reactance, so that the impedance of the antenna 3 can be reduced. As a result, even when the antenna 3 is lengthened, an increase in its impedance can be suppressed, the high-frequency current IR easily flows through the antenna 3, and the inductively coupled plasma P can be efficiently generated in the processing chamber 1. ..

However, in the plasma processing apparatus 100 of the present embodiment, the window member 22 includes the metal rolling sheet 221, and the holding frame 222 that holds the metal rolling sheet 221, as shown in FIG. The magnetic field transmitting window 5 is constituted by the above.

The rolled metal sheet 221 is formed by rolling (cold rolling or hot rolling) a metal (including an alloy) into a sheet shape, and is substantially parallel to the surface of the substrate provided in the processing chamber 1. Will be arranged. The metal constituting the rolled metal sheet 221 is, for example, one kind of metal selected from the group containing Cu, Al, Zn, Ni, Sn, Si, Ti, Fe, Cr, Nb, C, Mo, W or Co, or It is made of those alloys. In the present embodiment, the rolled metal sheet 221 is made of an alloy (specifically, high-strength titanium alloy) material containing titanium as a main component, but the material is not limited to this, and a stainless steel material or aluminum is contained as a main component. It may be made of an alloy material or the like. From the viewpoint of improving corrosion resistance and heat resistance, the surface of the rolled metal sheet 221 on the processing chamber 1 side may be subjected to coating treatment.

The thickness of the rolled metal sheet 221 is set so that the high frequency magnetic field generated from the antenna 3 can be transmitted to the processing chamber 1 side. If the thickness of the rolled metal sheet 221 is large, the high frequency magnetic field may not be able to be transmitted to the processing chamber 1 side. Therefore, the thickness of the rolled metal sheet 221 is the skin of the rolled metal sheet 221 at the frequency f of the high frequency current IR flowing through the antenna 3. It is preferable that the thickness is not more than d. The skin thickness d is specifically calculated by the following formula (1).

d=1/(π・f・μ・σ) ^1/2 (1)
(Here, f is the frequency of high frequency current (Hz), μ is the relative permeability of the rolled metal sheet 221, and σ is the electrical conductivity (S/m) of the rolled metal sheet 221.)

From the viewpoint of more efficiently supplying the high-frequency magnetic field to the processing chamber 1, the thickness of the rolled metal sheet 221 is more preferably 100 μm or less, and further preferably 90 μm or less. On the other hand, the thickness of the rolled metal sheet 221 is preferably 20 μm or more, and more preferably 30 μm or more from the viewpoint of ensuring the strength capable of withstanding the pressure difference between the inside and the outside of the processing chamber 1 during vacuum processing.

The holding frame 222 holds and holds the rolled metal sheet 221, and is detachably attached to the peripheral edge of the opening 212 of the container body 21 on the antenna 3 side, for example, via a gasket such as an O-ring. The holding frame 222 includes a first frame body 2221 arranged on the container body 21 side and a second frame body 2222 arranged on the antenna 3 side. The first frame body 2221 and the second frame body 2222 allow It is configured to sandwich the rolled metal sheet 221 from above and below. The above-mentioned rolled metal sheet 221 is adhered to at least the first frame body 2221 with an adhesive, and here, it is adhered to both the first frame body 2221 and the second frame body 2222. Thereby, the rolled metal sheet 221 and the holding frame 222 are vacuum-sealed. A vacuum epoxy adhesive may be used as the adhesive. Note that the rolled metal sheet 221 and the first frame body 2221 may be joined by welding instead of being bonded by an adhesive.

As shown in FIGS. 3 and 4, each of the first frame body 2221 and the second frame body 2222 has a plate shape, and is substantially parallel to the surface of the substrate provided in the processing chamber 1. It is arranged. The first frame body 2221 and the second frame body 2222 are respectively formed with long hole-shaped openings 2221a and 2222a penetrating in the thickness direction. The openings 2221a and 2222a of the first frame body 2221 and the second frame body 2222 are formed in substantially the same shape at the same positions of the first frame body 2221 and the second frame body 2222 when viewed from the antenna 3 side. The rolled metal sheet 221 is exposed to the processing chamber 1 side from the opening 2221a provided in the first frame body 2221 and is exposed to the antenna 3 side from the opening 2222a provided in the second frame body 2222. The exposed portion of the rolled sheet 221 forms the magnetic field transmission window 5.

In the first frame body 2221 and the second frame body 2222, openings 2221a and 2222a are provided at positions corresponding to the respective antennas 3. As a result, a separate magnetic field transmission window 5 is formed for each antenna 3. Here, three openings 2221a and 2222a are provided in parallel in each of the first frame body 2221 and the second frame body 2222, whereby three magnetic field transmission windows 5 corresponding to each of the three antennas 3 are arranged in parallel. Is formed in.

The first frame body 2221 and the second frame body 2222 are both made of metal and include, for example, Cu, Al, Zn, Ni, Sn, Si, Ti, Fe, Cr, Nb, C, Mo, W or Co. It may consist of one metal selected from the group or their alloys. The first frame body 2221 and the second frame body 2222 may be made of different materials, or may be made of the same material. Note that the first frame body 2221 and the second frame body 2222 may be electrically grounded.

Further, in the present embodiment, the holding frame 222 further includes a support beam 2223 for supporting the rolled metal sheet 221 in contact with it from the processing chamber 1 side, as shown in FIGS. 3 and 4. The support beam 2223 may be provided so as to come into contact with the rolled metal sheet 221 in a state where the processing chamber 1 is not evacuated. It may be provided so as to contact the rolled metal sheet 221 by bending to the side. The support beam 2223 is provided in the opening 2221a formed in the first frame body 2221 along the direction orthogonal to the longitudinal direction of the antenna 3 when viewed from the antenna 3 side. More specifically, the support beam 2223 is provided so as to be located between the conductor elements 31 adjacent to each other. As a result, the high frequency magnetic field generated from the antenna 3 and transmitted through the magnetic field transmission window 5 is not disturbed. The material forming the support beam 2223 may be the same material as the first frame body 2221 and the second frame body 2222, or may be a different material.

In the plasma processing apparatus 100 of the present embodiment, the metal rolling sheet 221 contacts the holding frame 222, and the holding frame 222 contacts the container body 21, so that the metal rolling sheet 221 and the holding frame 222 and the container body 21 are separated from each other. Thermally connected. Therefore, the heat generated in the rolled metal sheet 221 is released to the holding frame 222 and the container main body 21 to allow direct or indirect cooling.

The plasma processing apparatus 100 of the present embodiment may include a holding frame 222 (first frame body 2221, second frame body 2222 and support beam 2223) and a cooling mechanism (not shown) that cools the container body 21. The cooling mechanism may be one that cools the holding frame 222 and the container body 21 by means of water cooling or air cooling, for example. In the case of water cooling, the first frame body 2221 and the second frame body 2222 of the holding frame 222 and the container body 21 are cooled by having a hollow structure having a flow passage through which the cooling liquid flows. It may be configured as follows. In the case of air cooling, the holding frame 222 and the container body 21 may be cooled by blowing air with a fan or the like. Alternatively, the rolled metal sheet 221 may be directly air-cooled.

<Effects of this embodiment>
According to the plasma processing apparatus 100 of the present embodiment configured as described above, since the magnetic field transmission window 5 is made of a metal material having higher strength than a dielectric material such as ceramics, the thickness of the magnetic field transmission window 5 is large. Can be made smaller. Therefore, the distance from the antenna 3 to the processing chamber 1 (specifically, the surface of the magnetic field transmission window 5 on the processing chamber 1 side) can be reduced, and the high-frequency magnetic field generated from the antenna 3 can be efficiently supplied to the processing chamber 1. Can be supplied. Further, by forming the magnetic field transmission window 5 with a metal material, all the members of the vacuum container 2 surrounding the processing chamber 1, which is a plasma generation space, can be electrically grounded. Therefore, the influence of the voltage of the antenna 3 on the plasma P can be reduced, and the electron temperature and the ion energy can be reduced.

Further, since the window member 22 forming the magnetic field transmission window 5 is a member separate from the container body 21, the window member 22 is consumed even when the rolled metal sheet 221 is consumed due to corrosion by the gas G or deterioration due to heat. The rolled metal sheet 221 can be easily replaced and cleaned.
<Other modified embodiments>
The present invention is not limited to the above embodiment.

Although the window member 22 includes the rolled metal sheet 221 and the holding frame 222 in the above-described embodiment, the present invention is not limited to this. In another embodiment, the window member 22 may not include the holding frame 222 and may be configured by only the rolled metal sheet 221. In this case, the rolled metal sheet 221 is attached to the periphery of the opening 212 of the container body 21.

Further, in another embodiment, the holding frame 222 may not include the first frame body 2221 and may include only the second frame body 2222. Further, the holding frame 222 may not include the second frame body 2222 and may include only the first frame body 2221.

In the above embodiment, the magnetic field transmission window 5 is formed for each antenna 3, but the invention is not limited to this. In another embodiment, as shown in FIGS. 5 and 6, the magnetic field transmission window 5 may be formed for each conductor element 31 included in the antenna 3. In this way, the contact area between the rolled metal sheet 221 and the holding frame 222 can be increased, the rolled metal sheet 221 can be cooled more efficiently, and the rolled metal sheet 221 can be supported more reliably. You can Further, the present invention is not limited to this, and one magnetic field transmission window 5 may be formed for a plurality of antennas 3.

Although the holding frame 222 includes the support beam 2223 in the above embodiment, the present invention is not limited to this. In another embodiment, as shown in FIGS. 7 and 8, the holding frame 222 may not include the support beam 2223. By doing so, the distance between the conductor elements 31 can be shortened, so that the density of the plasma P formed in the processing chamber 1 can be made more uniform.

Further, in the above-described embodiment, the window member 22 is attached to the peripheral portion of the opening 212 of the container body 21 on the antenna 3 side, but the present invention is not limited to this. In other embodiments. The window member 22 may be attached to the peripheral portion of the opening 212 of the container body 21 on the substrate side.

Although the plasma processing apparatus 100 of the above-described embodiment includes the plurality of antennas 3, the present invention is not limited to this, and the antenna 3 may include only one antenna 3.

In the plasma processing apparatus 100 according to the above-described embodiment, the antenna 3 includes the plurality of conductor elements 31 and the capacitor 32, which is a quantitative element electrically connected in series with the conductor elements 31 adjacent to each other. Not limited to In other embodiments, the antenna 3 may have only one conductor element 31 and no capacitor 32.

Although the antenna 3 is a linear conductor in the above embodiment, the present invention is not limited to this and may be a spiral conductor or a dome-shaped coil.

In addition, it goes without saying that the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

<Evaluation of plasma emission intensity>
In the plasma processing apparatus 100 of the above-described embodiment, it was confirmed as follows that the high frequency magnetic field generated from the antenna 3 can be transmitted through the magnetic field transmission window 5 to generate the plasma P in the processing chamber 1. In addition, the present invention is not limited by the following experimental examples, it is also possible to carry out by making modifications within a range that is compatible with the gist, and they are all included in the technical scope of the present invention. It

Specifically, a rolled metal sheet 221 made of titanium alloy (Ti—Al—V) having a width of 90 mm×a length of 30 mm and a thickness of 35 μm was prepared, applied as the window member 22 and attached to the container body 21. Then, after the vacuum container 2 was evacuated, the pressure in the processing chamber 1 was adjusted to 18×10 ⁻³ Torr while introducing 7.0 sccm of Ar gas. Then, high-frequency power (frequency: 13.56 MHz) was supplied to the antenna 3 while changing the power value, and the emission intensity of the plasma P generated in the processing chamber 1 was measured by an emission spectroscopy analyzer. As can be seen from the results shown in FIG. 9, by applying the rolled metal sheet 221 as the magnetic field transmission window 5, the high-frequency magnetic field generated from the antenna 3 is transmitted through the magnetic field transmission window 5 to generate the plasma P in the processing chamber 1. We have confirmed that it can occur.

100 ・・・ Plasma processing apparatus 1 ・・・ Processing chamber 2 ・・・ Vacuum container 221 ・・・ Metal rolling sheet 3 ・・・ Antenna 4 ・・・ High frequency power supply 5 ・・・ Magnetic field transmission window G ・・・ Gas P・・・ Plasma IR ・・・ High frequency current

Claims (8)

A plasma processing apparatus for processing an object to be processed using plasma,
A vacuum container that forms a processing chamber that is evacuated and into which gas is introduced;
An antenna provided outside the processing chamber and connected to a high frequency power source to generate a high frequency magnetic field,
The vacuum container has a magnetic field transmission window for transmitting a high frequency magnetic field generated from the antenna into the processing chamber,
The plasma processing apparatus, wherein the magnetic field transmission window is made of a rolled metal sheet. The vacuum container comprises a container body and a window member attached to the container body and forming the magnetic field transmission window,
The plasma processing apparatus according to claim 1, wherein the window member includes the rolled metal sheet and a holding frame that holds the rolled metal sheet. The plasma processing apparatus according to claim 2, wherein the rolled metal sheet is bonded to the holding frame with an adhesive. The plasma processing apparatus according to claim 2, wherein the rolled metal sheet is thermally connected to the holding frame and the container body. The plasma processing apparatus according to claim 1, further comprising a support beam that contacts and supports the rolled metal sheet from the processing chamber side. The plasma processing apparatus according to claim 1, wherein a thickness of the rolled metal sheet is equal to or less than a skin thickness at a frequency of a high frequency current flowing through the antenna. The plasma processing apparatus according to claim 6, wherein the rolled metal sheet has a thickness of 20 μm or more and 100 μm or less. The rolled metal sheet is made of one metal selected from the group containing Cu, Al, Zn, Ni, Sn, Si, Ti, Fe, Cr, Nb, C, Mo, W or Co or an alloy thereof. The plasma processing apparatus according to claim 1.