JP3254069B2 - Plasma equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma apparatus.

[0002]

2. Description of the Related Art For example, taking a manufacturing process of a semiconductor device such as an LSI as an example, in various processes such as etching, ashing, CVD, and sputtering, in order to promote ionization and a chemical reaction of a processing gas,
2. Description of the Related Art In recent years, a plasma apparatus for generating plasma has been widely used. In recent years, as a pattern to be formed on an object to be processed, such as a semiconductor wafer (hereinafter, referred to as a “wafer”), has progressed, the energy density distribution of the plasma, From the viewpoint of adjusting the bias potential between the electrode and the susceptor with higher accuracy and reducing heavy metal contamination from the electrodes, a so-called high-frequency induction type plasma apparatus using a spiral antenna has been proposed.

[0003] For example, EP-A-379828
As described in Japanese Patent Application Laid-Open No. H11-260, a portion (generally, an upper wall portion) opposed to a wafer mounting table in an airtightly configured processing container (chamber) is formed of an insulating material such as quartz glass, and a spiral shape is formed on an outer wall surface thereof. Is fixed and a high-frequency current is applied to the antenna to create a high-frequency electromagnetic field in the processing container, thereby ionizing the processing gas supplied into the processing container and generating plasma. In a plasma apparatus using such a method, plasma is generated in a space in a processing container located directly below an antenna.

[0004]

However, the above-described conventional plasma apparatus has the following problems.
That is, in general, the plasma generation density is highest at a position corresponding to an intermediate portion between the center and the outside in the radial direction of the spiral antenna, and the plasma density decreases toward the inside and outside. ing. That is, the plasma density is not uniform. Therefore, the uniformity and reproducibility of the plasma treatment have not been sufficient. Also, a method for adjusting the plasma density has not been sufficiently disclosed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has improved uniformity and reproducibility in plasma processing by improving the uniformity of plasma density in the vicinity of a surface to be processed in a high-frequency induction system. It is another object of the present invention to provide a plasma device capable of adjusting the plasma density.

[0006]

According to the present invention, there is provided the following plasma apparatus. According to the present invention , first, a processing chamber configured to perform plasma processing on an object to be processed on a susceptor and a portion outside the processing chamber corresponding to the object to be processed are provided via an insulator. and a guide means for forming an induced electric field to the workpiece near the supply of high frequency power, comprising at least paramagnetic member a part of which is arranged so as to overlap with said guide means, said guide Means 2
It is composed of the above guide members, and each guide member is a single
These guide members are concentrically arranged in a spiral shape.
A plasma device is provided.

[0007] In such a case, a guide member constituting the guide means may be formed into a single spiral may be formed in a single loop.

[0008] Each guide member to further may be disposed them concentrically in a single loop.

[0009] If constituted by 2 or more inductive member guiding means as described above, the single spiral-shaped guide member may be a combination of a single loop-shaped guide member.

[0010] If the element is a plurality of induction member may be configured to independently control the high frequency power supplied to each induction member.

[0011]

Further, according to the present invention, a processing chamber configured to perform plasma processing on a processing object on a susceptor, and a portion corresponding to the processing object outside the processing chamber via an insulator. And an induction means for forming an induction electric field in the vicinity of the object to be processed by supplying high-frequency power, the induction means being constituted by a spiral- shaped induction member having a space region at the center thereof. A plasma device is provided.

In this case, the guiding means may be constituted by a spiral guiding member having a different pitch between the outer portion and the central portion. Further, a configuration may be employed in which a high-frequency application unit that applies a high-frequency bias to the object is provided.

[0014] Incidentally, is composed of a plasma generating unit and the plasma treatment unit, by introducing the plasma flow generated in the plasma generating portion in the processing chamber of the plasma processing unit, placed on a susceptor in the process chamber What is claimed is: 1. A plasma apparatus for performing plasma processing on a fixed object to be processed, wherein an antenna for forming an alternating electric field in said processing chamber through an insulating member by applying a high-frequency current to said plasma generating unit. Means, and first magnetic field forming means arranged to surround the plasma generating portion and form a static magnetic field in a direction perpendicular to the alternating electric field, and appropriately adjusting the alternating electric field and the static magnetic field. To form an electron cyclotron resonance region in the processing chamber, and further provided in the plasma processing section so as to surround the processing chamber. A second magnetic field forming means for shaping and holding the plasma flow introduced into the processing chamber to the object to be processed, wherein the insulating member forms at least a part of a wall of the processing chamber. The antenna device may be a single spiral antenna arranged substantially parallel to the outer wall surface of the insulating member .
No.

[0015] In such a case, forming a plasma generating chamber before Symbol insulating member communicates with the processing chamber, wherein the antenna means may be arranged constitutes the outer peripheral portion of the plasma generation chamber so as to at least one winding .

[0016]

The previous Symbol insulating member further constitutes at least part of the wall of the processing chamber, said antenna means is constituted by two or more antenna member arranged substantially in parallel to the outer wall portion surfaces of the insulating member The antenna members may be concentrically arranged as spiral antennas.
Further, in this case , each antenna member may be arranged in a concentric manner as a loop antenna.

[0018] or the previous SL antenna member provides two and spiral antenna and loop antenna, appropriately combined, it may be made to place these concentrically.

[0019] Then when the antenna member is a plurality in each plasma apparatus described above, the high-frequency current applied to these respective antenna member may be constructed as to be controlled each independently.

[0020] 100MH before Symbol antenna means was Saranima
The ECR condition may be achieved by passing a high-frequency current having a frequency equal to or lower than z and forming a magnetic field having a magnetic flux density corresponding to the frequency by the first magnetic field forming means.

[0021] On the other hand, according to claim 8, the process chamber of a plasma apparatus for performing a plasma process on the target object, for generating plasma disposed outside of the processing chamber
A first spiral antenna, a second spiral plasma-generating antenna disposed outside the first antenna, and a high-frequency power supply for supplying high-frequency power to the first antenna and the second antenna. A plasma device characterized by having a high-frequency power supply is provided. In this case, the first antenna and the second antenna each have an inner terminal and an outer terminal, and the high-frequency power may be supplied from the inner terminal. Good. The high-frequency power supply may be shared by one high-frequency power supply, for example, by using a power distribution circuit. The first antenna and the second antenna may have different lengths. The first antenna and the second antenna include:
You may comprise so that high frequency electric power may be supplied via a capacitor. Furthermore, high-frequency currents having different current values may flow through the first antenna and the second antenna.

[0022]

[0023]

[0024]

[0025]

[0026]

According to the present invention , since the induction means for forming the induction electric field near the object to be processed by the supply of the high-frequency power and a part of the paramagnetic material overlap, the generated magnetic flux is generated by the paramagnetic material. Does not penetrate. This makes it possible to displace the generated region of the generated plasma. In such a case, the guide member constituting the guide means is a single or one spiral, in the case of shaped single loop, relatively uniform plasma is generated.

[0028] or a pre-Symbol inductive means and be constituted by two or more guide members, each guide member of these concentric as these or is arranged concentrically, single looped as a single spiral Also, the magnetic field strength of the concentric alternating electric field induced can be adjusted. In such a case, the single spiral-shaped guide member, the same effects as be a combination of a single loop-shaped guide member is obtained, thereby enabling more various adjustments.

[0029] When the And induction member is configured to control each independently of the high-frequency power supplied to each guide member in some cases more than by the strength of the alternating electric field induced by the individual guide member Because it can be adjusted, it is possible to control the plasma density extremely finely and over a wide range.

[0030] In the plasma apparatus constructed as described above, when the paramagnetic material member and the plate is easy to adopt as a space to device configuration Moreover,
The penetration of magnetic flux can be blocked evenly. For paramagnetic member further Nico when made of copper, the conductive is good,
This is preferable for the generation of eddy currents that hinder magnetic flux.

According to the third aspect, the guiding means for forming the induced electric field in the vicinity of the object to be processed by supplying high-frequency power is constituted by a spiral guiding member having a space region at the center thereof. As a result, the number of magnetic fluxes penetrating the center portion in the vertical direction decreases, the magnetic field strength of the induced alternating electric field decreases, and the plasma generation region is displaced outward in the radial direction. Therefore, by utilizing this, it is possible to make the plasma density uniform.

In this case, if the guiding means is constituted by a spiral guiding member having a different pitch between the outer portion and the center portion, the alternating electric field induced between the outer portion and the center portion is relatively dense and dense. It is possible to make the plasma density uniform using this.

If [0033] or is found a structure provided high frequency applying means for applying a high frequency bias to the workpiece, it is possible to further accelerate the ions in the plasma.

[0034] Incidentally, configured to form an alternating electric field in the processing chamber via an insulating member by applying a high-frequency current to the installed antenna means to the plasma generating portion, a micro wave of the ultrasonic <br/> frequency if configured to achieve the ECR condition without using, it is possible to set the frequency domain utilizing a relatively low region, for example 100MHz or less.
Therefore, even if the magnetic flux density of the static magnetic field formed in the direction orthogonal to the alternating electric field by the antenna means is reduced, the ECR
The condition can be achieved, and the size of the first magnetic field forming means for that purpose can be reduced. Also, ECR
Since a small magnetic field is required to achieve the condition, the influence of the diverging magnetic field on the plasma flow can be minimized.

Further, in the present invention , the second magnetic field forming means is provided so as to surround the processing chamber. Therefore, the expansion area of the plasma flow introduced into the processing chamber is enlarged to a planar shape near the object to be processed, and a uniform plasma flow is maintained in the processing area, and the direction of the plasma flow is directed to the processing surface of the object to be processed. It is possible to orient it vertically.

The insulating member communicates with the processing chamber.
A plasma generation chamber is formed, and the antenna means
Arranged so that the outer circumference of the generation chamber is wound at least once
In this case, the plasma state can be controlled by the number of turns of the antenna means. For example, if a cylindrical plasma generation chamber is formed by an insulating member and its outer periphery is surrounded by antenna means, a uniform alternating electric field can be formed substantially at the center of the plasma generation chamber. Since the plasma generation unit and the plasma processing unit can be separated, it is possible to set and control different parameters for the plasma generation conditions and the plasma processing conditions, and to perform more accurate plasma processing. Can be.

Further, according to the present invention , at least a part of the wall of the processing chamber, for example, the upper surface is constituted by the insulating member, and the spiral antenna is arranged substantially parallel to the outer wall surface of the insulating member. With such a configuration, since the ECR region can be formed directly near the inner wall surface of the insulating member, the device can be simplified and downsized. Sa
Its spiral antenna when it is arranged in two or more concentrically et
In this case, it is possible to control the plasma density over a wider range . Similar effects can be obtained when the respective antenna members are arranged as concentric loop antennas.

[0038] or when the combination of the spiral antenna and loop antenna allows for more control of a wide range of plasma density.

[0039] And a high-frequency current applied to the lever these respective antenna members, if as configured to control each independently,
More precise and wide-range control of the plasma density is possible.

When a high-frequency current having a frequency of 100 MHz or less is passed through the antenna means and a magnetic field having a magnetic flux density corresponding to the frequency is formed by the first magnetic field forming means so as to achieve the ECR condition, The magnetic flux density of the static magnetic field can be reduced, making the entire device simpler and
It is possible to reduce the size.

[0041]

[0042]

[0043]

[0044]

When a high-frequency current is passed through the dielectric electric field forming means, a demagnetizing field is formed in the magnetic pole material disposed near the dielectric electric field forming means, which may act on the magnetic field in the processing chamber. The problem can be solved by giving the material a certain thickness or making the magnetic path longer. did
Using soft ferrite Therefore, it is easy to adopt such a form.

[0046]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. FIGS. 1 and 2 are a perspective view and a sectional view schematically showing the structure of a plasma apparatus according to a first embodiment of the present invention. As shown in FIG. 1, a chamber 2 in which a processing chamber of the plasma apparatus 1 is formed has a bottom wall and side walls made of metal, for example, aluminum, and an upper wall 3 made of an insulator, for example, quartz glass ( It is configured as a cylindrical hermetic container made of silica glass or ceramic material. When transparent quartz glass is used for the upper wall 3, it is possible to visually confirm the light emission state of the plasma in the chamber 2.

A disk or columnar mounting table (susceptor) 4 is disposed at the center of the bottom of the chamber 2, and, for example, a wafer W as an object to be processed is mounted on the mounting table 4. ing. The mounting table 4 is made of, for example, aluminum whose surface is anodized. When the plasma device 1 is configured as an etching device,
The mounting table 4 has an etching frequency of 13.56 via a capacitor 5 as a matching circuit.
A high frequency power supply 6 of MHz is connected.

The inside of the mounting table 4 is supplied with cooling water from a cooling water supply unit (not shown) to prevent high-frequency heating. By providing such a high-frequency power source 6 and appropriately applying a high-frequency bias to the mounting table 4 in accordance with the processing gas and gas pressure to be used, the ions in the plasma flow are accelerated and the ion flow is made uniform. It is possible to achieve.

A focus ring 7 made of quartz surrounding the wafer W as an object to be processed is provided on the upper surface of the mounting table 4 so as to be higher than the surface to be processed of the wafer. The focus ring 7 has a function of concentrating the plasma generated above the mounting table 4 on the surface to be processed of the wafer W to increase the plasma processing efficiency. For example, in the case of an etching process, an etching rate is used. Has the effect of increasing Also this focus ring 7
Has a function of preventing the exposed portion of the mounting table 4 made of aluminum, on which the wafer W is not mounted, from being etched by the plasma and generating dust.

An electrostatic chuck 10 is provided on the wafer holding surface of the mounting table 4. The electrostatic chuck 10 has a structure in which a copper foil 11 as an electrode is covered with an insulating film, for example, a polyimide resin, and has a function of accurately attracting and holding the wafer W by electrostatic force. This electrostatic chuck 10
Is connected to a DC power supply 12.
For example, when a voltage of, for example, 2 kV is applied to the electrostatic chuck 10, the wafer W as a processing target is attracted and held on the electrostatic chuck 10.

A gas inlet 13 is provided in the upper part of the side surface of the chamber 2, and the gas inlet 13 is connected to the gas supply pipe 1.
4 are connected. Then, a processing gas is supplied from a separately provided gas supply source 15 into the chamber 2 through the gas supply pipe 14. In this case, the supplied processing gas varies depending on the type of processing. For example, in the case of etching processing, an etching gas such as CHF ₃ or CF ₄ is supplied. In the illustrated example, one gas supply source 15 and one gas supply pipe 14 are shown, but a number of gas supply sources and gas supply pipes corresponding to the type of the processing gas are connected to the chamber 2. You may.

A gas outlet 16 is provided at a lower portion of the side surface of the chamber 2, and a gas exhaust pipe 17 is connected to the gas outlet 16. This gas exhaust pipe 17 is connected to an exhaust system 18 composed of a vacuum pump or the like.
The inside of the chamber 2 is configured to be evacuated to a predetermined degree of reduced pressure.

Further, on the outer wall surface of the upper wall 3 of the chamber 2 facing the wafer W mounted on the mounting table 4 in the chamber 2, a spiral high-frequency antenna 20 as a guide member is provided. It is arranged. The antenna 20 is made of a linear or tubular conductive material, and is preferably made of copper having excellent cooling characteristics. Between the inner terminal 20a and the outer terminal 20b of the antenna 20, for example, a frequency of 13.56 MHz is supplied from a high frequency power supply 21 for plasma generation via a capacitor 22 as a matching circuit.
Is applied. With this configuration, a high-frequency current iRF flows through the antenna 20, and the chamber 2 directly below the antenna 20 as described later.
An induced electric field is formed in the inner space, thereby generating a plasma of the processing gas. The high frequency power supplies 6 and 2
1 is controlled by the controller 23.

In the first embodiment, a circular thin plate 24 made of a paramagnetic metal such as copper is interposed between the center of the antenna 20 and the upper wall 3 made of quartz glass. The diameter of the thin plate 24 is appropriately selected and set according to the shape and dimensions of the antenna 20, the output power of the high-frequency power supply 21, the diameter of the wafer W, the distance between the antenna 20 and the wafer W, and the like. The thin plate 24 adjusts the alternating magnetic field B in the space inside the chamber 2 immediately below the antenna 20 as described later, and the alternating electric field E induced thereby.
Is adjusted, and as a result, the plasma is diffused, so that the plasma density is made uniform near the surface of the wafer W.

The plasma apparatus 1 according to the first embodiment is configured as described above. Next, plasma generation and plasma processing in the plasma apparatus according to the present embodiment will be described with reference to FIG. The wafer W to be processed is transferred from a load lock chamber (not shown) adjacent to the chamber 2 into the chamber 2 evacuated to a reduced pressure atmosphere, for example, 10 ⁻⁶ Torr in advance, and the mounting table in the chamber 2 is set. 4 and is attracted and held by the electrostatic chuck 10.
Next, a predetermined processing gas, for example, CHF ₃ or CF ₄ is introduced into the chamber W through the gas supply pipe 14. At this time, the pressure in the chamber 2 is, for example, 1
It is adjusted to 0 ^-3 Torr.

In this state, a high-frequency voltage from a high-frequency power supply 21 is applied to the antenna 20. By applying the high-frequency voltage, a high-frequency current iRF
Flows, an alternating magnetic field B is generated around the conductor of the antenna 20, and most of the magnetic flux passes through the center of the antenna in the vertical direction to form a closed loop. Such an alternating magnetic field B induces a substantially concentric circular alternating electric field E immediately below the antenna 20, and the electrons accelerated in the circumferential direction by the alternating electric field E collide with neutral particles of the processing gas. By doing so, the gas is ionized and plasma is generated.

As shown schematically in FIG. 2, the plasma generated just below the antenna 20 has the highest plasma density at a position corresponding to an intermediate portion between the center and the outside in the radial direction of the antenna 20. The plasma density is higher, and the plasma density becomes lower toward the inside and outside. However, in the present embodiment, an eddy current flows in the circular thin plate 24 so as to prevent the penetration of the magnetic flux B.
Becomes difficult to pass through the center of the antenna, and passes outside the magnetic flux B 'indicated by a dotted line when there is no thin plate 24. For this reason, the plasma generation region P directly below the antenna is displaced radially outward from the plasma generation region P 'indicated by the broken line when there is no thin plate 24.

In the absence of the thin plate 24, the plasma diffuses from the high-density region to the low-density region, and the plasma density is leveled near the wafer W. As a result, as shown by Pd 'in FIG.
The plasma density near the center of the wafer W becomes higher than the plasma density near the outer peripheral edge of the wafer. Therefore, the wafer W
Uneven treatment is performed on the surface.

On the other hand, when the thin plate 24 is present, as described above, the plasma generating region P displaced radially outward from the plasma generating region P 'indicated by the broken line without the thin plate 30 is formed. Since the plasma is formed, the plasma diffuses in the radial direction and downward, and the plasma density is leveled near the wafer W, and the plasma density is leveled almost uniformly in the radial direction near the surface of the wafer W as indicated by Pd in FIG. Is done.
Therefore, ions, electrons, and other active species contained in the plasma are uniformly supplied or irradiated to the entire surface of the semiconductor wafer W, and a predetermined plasma process is uniformly performed on the entire wafer surface.

For example, in plasma etching, gas molecules excited into an active state by plasma chemically react with a material to be processed on a wafer surface to vaporize a reaction product, and the wafer surface is scraped off. In plasma CVD, gas molecules excited into an active state by plasma react with each other, and a reaction product is deposited on a wafer surface to form a CVD film. As described above, in any of the plasma processes, when the plasma apparatus according to the first embodiment of the present invention is used, the plasma acts on the entire surface of the wafer W at a uniform density, so that the plasma is uniform on the wafer surface. Processing is performed.

When the predetermined processing for the wafer W is completed in the chamber 2 as described above, after the residual processing gas and the reaction products in the chamber 2 are sufficiently exhausted by the exhaust system 18, the transfer arm (shown in FIG. 3), the wafer W on the mounting table 4 is carried out to the load lock chamber, and the process ends.

As described above, in the plasma device 1 of the first embodiment, the thin plate 24 as a paramagnetic metal member, which is disposed so as to overlap with a part of the antenna 20 as an inducing member (for example, the center of the antenna), has a magnetic flux. , The alternating electric field E is weakened at the position of the space in the chamber 2 corresponding to the thin plate 24, and the plasma generation density is also lowered. Therefore, when the thin plate 24 is provided at the center of the antenna 20, the plasma generation region P immediately below the antenna is displaced radially outward, and as a result, the plasma density on the surface of the wafer W (the surface to be processed) is reduced. Be uniformed. This makes it possible to perform uniform and reproducible plasma processing on the wafer W to be processed.

In the first embodiment, the antenna 20 as the guide member is formed in a spiral shape as described above. However, the present invention is not limited to this. For example, as shown in FIG. Terminal 31a at each end thereof.
The antenna 31 may include the antenna 31b. In the case of the ring-shaped antenna 31 as well, an alternating electric field is formed by the same mechanism as in the case of the spiral shape, and relatively uniform plasma is formed.

As shown in FIG. 5, the antenna 35 may have a shape in which the center of the spiral is cut off. Also in these cases, the plasma density is made more uniform due to the above-mentioned action of the thin plate 24 which is a paramagnetic metal member. In the case of the antenna 35 shown in FIG. 5, the diameter of the space region at the center is the number of spirals (turning number) of the antenna, the output power of the high frequency power supply 21 connected to its terminals 35a and 35b, and the object to be processed. It is appropriately selected and set according to the diameter of the wafer W, the distance between the antenna 35 and the wafer W, and the like.

The paramagnetic metal member is not limited to the circular thin plate 24 described above. The paramagnetic metal member may be arranged at a place other than the center of the antenna as long as it is arranged near the antenna serving as the guide member. Section). Further, the paramagnetic metal member according to the present invention may be disposed so as to overlap on the antenna.

Next, a second embodiment of the present invention will be described. In the present embodiment, the same basic device configuration as a plasma device such as a chamber as in the first embodiment is used. However, in the second embodiment, the paramagnetic metal member is not used, and the plasma density is adjusted by changing the state of the spiral antenna. That is, in the second embodiment, in the plasma apparatus 1 shown in FIGS. 1 and 2, the thin plate 24 is removed, and the antenna 40 shown in FIG.

FIG. 6 shows an antenna 40 as a guiding member.
Has a spiral shape having a space region in the center. As described above, in the spiral antenna 40 having a space area in the center, the number of magnetic fluxes penetrating the antenna center in the vertical direction decreases, so that the magnetic field strength of the alternating electric field induced by the diameter decreases, As in the first embodiment, the plasma generation region is displaced outward in the radial direction. Therefore, the plasma density is made uniform by the same operation as in the first embodiment. In this case, since the paramagnetic metal member used in the first embodiment does not exist, the diameter R of the space region in the center of the antenna needs to be larger than the diameter of the antenna 35 in FIG. A diameter corresponding to the diameter of the wafer is selected.

However, also in the case of the antenna 40 shown in FIG. 6, the diameter of the space region in the center portion is determined by the number of spirals (turning number) of the antenna 40, the output power of the high-frequency power source 21 connected to the terminals 40a and 40b, Needless to say, it is appropriately selected according to the diameter of the wafer to be processed, the distance between the antenna 40 and the wafer, and the like.

In the example shown in FIG. 7, in the spiral (or spiral) antenna 45, the pitch of the antenna conductors is changed in the radial direction, and the antenna conductor is densely arranged outside the antenna and sparsely arranged at the center of the antenna. . According to such a spiral structure, the concentric alternating electric field induced immediately below the antenna becomes relatively small in the inner peripheral portion (center portion), so that the plasma generation region also shifts outward in the radial direction. The same effect as in the first embodiment can be obtained, and the plasma density can be made more uniform.

Next, the third embodiment will be described. In the third embodiment, the basic device configuration as a plasma device such as a chamber is the same as that of the first embodiment. Two antennas as members,
The antennas are provided concentrically and configured so that high-frequency voltages supplied to these two antennas are controlled independently of each other. That is, in the third embodiment, in the plasma device 1 shown in FIGS. 1 and 2, the thin plate 24 is removed, and the antenna 20, the high-frequency power source 21, and the capacitor 22 are replaced with the ring-shaped antenna 51 shown in FIG. 52 and a high-frequency power supply for applying high-frequency power thereto.

In FIG. 8, the ring-shaped antennas 51 and 5
2 are provided concentrically, preferably on the same plane, and a first high-frequency power supply 54 is connected to terminals 51a and 51b of the outer antenna 51 via a capacitor 53 as a matching circuit. On the other hand, between the terminals 52a and 52b of the inner ring-shaped antenna 52, a second high frequency power supply 56 is connected via a capacitor 55 as a matching circuit.

The first and second high frequency power supplies 54, 5
6 supplies independent first and second high-frequency powers to the outer and inner ring antennas 51 and 52 at the same frequency (for example, 13.56 MHz) and in the same phase. When the antenna is basically arranged at the same position as in FIGS. 1 and 2, the position where the second high frequency power is lower than the first high frequency power is selected.

Thus, the outer ring-shaped antenna 5
1, a relatively large high-frequency current iARF flows, and a relatively small high-frequency current iBRF flows through the inner ring-shaped antenna 52. In this case, the plasma generation region P in the space inside the chamber 2 immediately below the antenna is the same high-frequency current iRF as the single antenna 20 shown in FIG.
Is shifted to the outside of the plasma generation region P 'when the gas flows, so that the plasma density can be made uniform by the same operation as in the first embodiment.

In this case, as shown in FIG. 8, the outer ring-shaped antenna 51 and the inner ring-shaped antenna 5 are used.
And a wafer W as an object to be processed
It is preferable to arrange the antennas so that is located in order to further uniform the plasma density. The number of ring-shaped antennas is not limited to two as shown in FIG. 8, but may be three or more.

Further, by configuring the antenna as the guiding member in this way, the high frequency power can be set independently for the inner antenna and the outer antenna, so that the plasma generation region can be controlled more precisely and over a wide range. . By providing a power distribution circuit between the high-frequency power supply and the antennas 51 and 52, the first and second high-frequency power supplies 51 and 52 can be shared by one high-frequency power supply.

FIG. 9 shows an example in which two spiral antennas 61 and 62 are arranged concentrically. That is, the spiral antenna 62 is provided inside the spiral antenna 61,
The corresponding high-frequency power supplies 65 and 66 are connected via capacitors 63 and 64, respectively. Again, in this case,
The same effect as the example shown in FIG. 8 can be obtained. The number of turns of each of the spiral antennas 61 and 62 depends on the output of each high-frequency power supply,
It can be arbitrarily selected according to the diameter of the wafer to be processed, the distance between the antenna and the wafer, and the like.

FIG. 10 shows an example in which a spiral antenna 71 and a ring antenna 72 are arranged concentrically.
In this case, the same effect can be obtained. The ring-shaped antenna 72 may be inside as shown in FIG. 10, or the ring-shaped antenna 72 may be outside.
Each antenna 71, 72 has a capacitor 63,
Corresponding high frequency power supplies 65 and 66 are connected via 64.

In the examples shown in FIGS. 8 to 10, the paramagnetic metal member used in the first embodiment can be used together. In that case, the plasma can be adjusted using both the high frequency power and the paramagnetic metal.

Next, the fourth embodiment will be described.
The embodiment is an example in which the present invention is applied to an ECR plasma etching apparatus. First, an apparatus configuration of a plasma apparatus 81 according to a fourth embodiment will be described with reference to FIGS.

The plasma device 81 is composed of a plasma generator A and a plasma processor B as schematically shown in FIG. The plasma generating section A includes, for example, a cylindrical quartz tube 82 having a dome-shaped top portion, an antenna unit 83 surrounding the quartz tube 82, and an electromagnetic device disposed above the antenna unit 83 so as to surround the quartz tube 82. And a coil 84.

The antenna means 83 is connected to a first high-frequency power supply 86 via a matching box 85, and can apply a high-frequency current in response to a command from a controller 87. The electromagnetic coil 84 is connected to a power supply 88 so as to excite a desired static magnetic field in response to a command from the controller 87. At the top of the dome portion of the quartz tube 82, a first gas supply which can introduce a first process gas, for example, an inert gas such as argon, from a first gas source 89 via a mass flow controller (not shown). A conduit 90 is attached.

As shown in detail in FIG. 12, the antenna means 83 comprises an upper ring member 83a, a lower ring member 83b, and a connecting member 83c for connecting both rings. As shown by an arrow in FIG. 12, an alternating electric field can be formed in the cylindrical quartz tube 82 by applying a desired high-frequency current through a matching box 85. Note that the structure of the antenna is not limited to the above shape, as long as the alternating electric field can be formed in a desired region.

As apparent from FIGS. 12 and 13, the electromagnetic coil 84 is disposed above the antenna means 83 so as to surround the cylindrical quartz tube 82. In FIG. 12, in order to facilitate understanding of the structure, substantially half of the electromagnetic coil 84 is shown in a cut-out state. As indicated by an arrow in the plan view of FIG. 13, the electromagnetic coil 84 is excited by the power supply 88, so that a direction orthogonal to the alternating electric field, that is, a vertical direction (axial direction of the cylindrical quartz tube) in the illustrated example is downward. To form a static magnetic field directed toward

The dimensions and output of the quartz tube 82, the antenna means 83, and the electromagnetic coil 84 constituting the plasma generating section are approximately 20 to 20 cm above the reaction surface of the wafer W to be processed, as described later. Around 30 cm, that is, FIG.
In the example, the adjustment is performed so that an ECR region (Ec) is formed in the vicinity of a connection portion between the quartz tube 82 and a processing chamber 91 described later.

Referring again to FIG. 11, the configuration of the plasma processing section B of the plasma device 81 according to the fourth embodiment will be described. The plasma processing section B includes a processing chamber 91 for processing an object to be processed, for example, a wafer W, by a plasma flow generated by the plasma generating section A, and mounts and fixes the wafer W in the processing chamber 91. Susceptor 92 is stored. The susceptor 92 is connected to a second high frequency power supply 94 via a matching box 93, and can apply an RF bias to the susceptor 12 when performing an etching process in accordance with a command from the controller 87. It is configured as follows.

A second gas supply line 99 through which a second process gas can be introduced from a second gas source 98 via a mass flow controller (not shown) is provided at a shoulder opening of the processing chamber 91.
An exhaust pipe 96 communicating with an exhaust system 95 such as a vacuum pump is provided below the processing chamber 91 on the opposite side.
Are connected, and the processing chamber 91 is selected according to the processing step.
Process gas is introduced into the processing chamber 9 or
1 is configured to be able to evacuate the inside.

Further, according to the present embodiment, the processing chamber 91
The magnetic field forming means 97 is arranged so as to surround the side wall of. As shown in detail in FIG. 14, the magnetic field forming means 97 is composed of a plurality of permanent magnets 97a, 97b and the like alternately arranged in an annular shape with different polarities. Is formed. By the action of the multipolar magnetic field, as described later, the plasma flow introduced from the plasma generator A can be shaped and held near the processing surface of the wafer W to be processed.

The plasma apparatus 81 according to the fourth embodiment is configured as described above. Next, the operation thereof will be described. When performing an etching process, a load arm (not shown) is moved from a cassette chamber (not shown) by a transfer arm. The wafer W, which is the object to be processed, transferred to the processing chamber is transferred from the load lock chamber to the processing chamber 9
1 is transported. That is, a reduced pressure atmosphere, for example, 10 ^-6
It is transported into the processing chamber 91 set to Pa, and is mounted and fixed on the susceptor 92 in the processing chamber 91 by a fixing means such as an electrostatic chuck (not shown).

Next, the wafer W is supplied from the first gas supply line 90 at the top of the dome of the quartz tube 82 and the second gas supply line 99 provided at the shoulder of the processing chamber 91.
A predetermined process gas for performing plasma etching on the quartz tube 82 and the processing chamber 91 is introduced.
At this time, the pressure in the processing chamber 91 is adjusted to, for example, 10 ⁻³ Torr. For example, the first gas supply line 90
It is possible to supply an inert gas such as argon through the second gas supply line and supply Cl ₂ or CHF ₃ from the second gas supply line 99. As described above, by configuring the process gas to be supplied to the plasma generation unit A and the plasma processing unit B from the two series gas supply pipes, the optimum mixing ratio of the process gas for etching can be set to the plasma generation unit A. In each of the plasma processing unit B and the plasma processing unit B, a plasma etching process with more controllability can be performed by separately setting parameters.

When plasma is generated, an appropriate high-frequency current is sent from the first high-frequency power supply 86 to the antenna means 83 to form an alternating electric field in the processing chamber 91 and the electromagnetic coil 84 is turned on by the power supply 88. The excitation forms a static magnetic field having magnetic lines of force vertically downward, that is, in the axial direction of the quartz tube 82. And EC to be described later
When the R condition is satisfied, the electrons existing in the ECR region spirally move around the magnetic field lines of the magnetic field, reach the plasma potential, and are accelerated in the weak magnetic field direction, that is, vertically downward. As a result, it is possible to form a plasma flow directed in a direction perpendicular to the processing surface of the wafer W to be processed.

Here, electron cyclotron resonance (EC
R) conditions is obtained by satisfying _{B = 2πm e f c / e} . However, in the above equation,
B is the magnetic flux density, m _e is the electron mass, the f _c frequency, e is the charge. Therefore, in a conventional microwave ECR plasma apparatus, 2.45 GHz that can be industrially used is used.
8 as a magnetic field that satisfies ECR conditions for microwaves
Since 75 Gauss was required, a large heavy magnet was required to obtain a magnetic field, and the apparatus had to be enlarged. Also, a special waveguide for propagating microwaves was required.

However, if a low frequency is used, it is possible to achieve the ECR condition with a lower magnetic field.
It is clear from the above equation. Therefore, according to the plasma device 81 according to the present embodiment, for example, 10
By supplying a high-frequency current of 0 MHz or less, an alternating electric field can be formed.
If a very small magnetic field of about s is formed, the ECR condition can be satisfied. Therefore, it is sufficient to use an electromagnetic coil that is much smaller than that of the conventional device, so that the device can be simplified and downsized.

As shown in FIG. 13, the magnetic field lines formed by the first magnetic field forming means form a divergent magnetic field that warps outwardly from the processing chamber as it goes vertically downward. Therefore, the plasma flow toward the processing target W also tends to diverge. In particular, in a conventional microwave ECR plasma apparatus, 8
Since a large magnetic field of 75 Gauss must be used, the divergent magnetic field formed in the processing chamber 91 is also large, the divergence tendency of the plasma flow is also large, and the wafer W
It was difficult to make the plasma flow vertically incident on the treated surface.

However, according to the plasma apparatus 81 according to the present embodiment, since a small magnetic field such as 35 Gauss can be used, the divergent magnetic field generated in the processing chamber 91 can be reduced. It is possible to minimize the tendency of the introduced plasma flow to diverge. In particular, the influence of the divergent magnetic field can be almost ignored at a point about 20 to 30 cm away from the ECR region, and the plasma flow can be guided vertically to the processing surface of the wafer W, so that the selectivity is high. Good anisotropic etching can be achieved.

Further, a multi-pole magnetic field forming means 97 as shown in FIG. 14 is arranged around the processing chamber 91 of the plasma apparatus 1 shown in FIG. Can be shaped and held so as to correspond to the processing surface of the workpiece W. In addition, it is possible to secure a high selectivity and uniform etching by reducing the above-mentioned tendency of the plasma flow to diverge by the multi-pole magnetic field forming means 97 and making the plasma flow perpendicular to the processing surface. Become.

In the embodiment shown in FIG.
2 is configured to be able to apply an RF bias from a second high frequency power supply 94 via a matching box 93. Therefore, by appropriately applying an RF bias according to the processing gas or gas pressure used,
It is possible to accelerate the ions in the plasma flow and make the ion flow uniform.

As described above, the wafer W to be processed is
Is completed, the exhaust pipe 96 is opened, and the residual processing gas and reactive products in the processing chamber 11 are sufficiently exhausted by the exhaust system 95 such as a vacuum pump. A gate valve (not shown) provided is opened, and the object to be processed on the susceptor is carried out to the load lock chamber by the transfer arm. The above is the description of the operation when the plasma device 1 according to the fourth embodiment is used.

Next, still another embodiment relating to a process gas introduction route from the first gas supply line 90 in the top dome portion of the quartz tube 82 will be described with reference to FIGS.
This will be described with reference to FIG. In the fourth embodiment shown in FIG. 11, the processing gas is directly introduced into the quartz tube 82 from the first gas supply line 90 formed in the top dome portion of the quartz tube 82. In order to disperse uniformly and quickly in the chamber 91, the configuration shown in FIG. 15 or FIG. 16 can be adopted. In another embodiment shown in FIG. 15, the processing gas is introduced through a plate member 101 in which a plurality of through holes 100 are formed, thereby achieving uniform and accelerated gas dispersion.

In another example shown in FIG. 16, a sponge-like porous material 102 is provided in the vicinity of the first gas supply pipe 90, and the processing gas is a fine gas in the porous material 102. The gas is introduced into the plasma generating section A through the hole 103 so that the gas can be dispersed uniformly and accelerated.

Next, referring to FIG. 17 and FIG.
An example will be described. However, for components having the same function and structure as the first embodiment shown in FIG.
The same numbers are given to omit redundant description. In the fifth embodiment, a quartz tube 8 shown in FIG.
Instead of the quartz plate 110, a quartz plate 110 is disposed on the upper surface of the processing chamber 91, and an antenna unit 111 is provided on the outer surface of the quartz plate 110.

As shown in FIG. 18, this antenna means 111 is a spiral antenna having a spiral shape, and is capable of efficiently forming an alternating electric field by applying a high-frequency current from a high-frequency power supply 86 via a matching box 85. Is possible. Note that the antenna structure installed on the outer surface of the quartz plate 110 is not limited to the above shape, as long as a desired alternating electric field can be formed in a desired region.

For example, various types of antennas shown in FIGS. 4 to 10 can be used.
To the high frequency power supply and the capacitor shown in FIG. Moreover, by configuring the antenna, the connection of the high-frequency power supply, and the like as described above, as described in the corresponding part, the plasma density can be made uniform and more uniform plasma processing can be performed. .

Also in the fifth embodiment, FIG.
As in the embodiment shown in FIG. 1, an electromagnetic coil 84 is provided above the antenna means 111 so as to be able to form a static magnetic field having lines of magnetic force gradually diverging downward in the vertical direction. I have. Thus, also in the present embodiment, by appropriately adjusting the outputs of the antenna means 111 and the electromagnetic coil 84, a desired area,
For example, an ECR region can be formed in a region of 20 to 30 cm above the processing surface of the object to be processed.

Further, according to the present embodiment, it is not necessary to use a bulky component such as the quartz tube 82 in the plasma apparatus 81 according to the first embodiment shown in FIG. It is possible to reduce the size.

Next, a sixth embodiment will be described with reference to the accompanying drawings. This embodiment is an example applied to a plasma etching apparatus, and as shown in FIG. 19, a plasma etching apparatus 121 according to the sixth embodiment. Has an airtight processing chamber 122 made of, for example, aluminum. A susceptor 123 is disposed substantially at the center of the processing chamber 122, and an object to be processed is placed on the susceptor 123.
For example, the wafer W is mounted and fixed.

A processing gas supply pipe 124 is attached to a shoulder opening of the processing chamber 122. Cl ₂ or C ₂ is supplied from a gas source 125 via a mass flow controller (not shown).
A reactive gas such as HF ₃ can be supplied into the processing chamber 122. An exhaust pipe 126 is installed below the processing chamber 122 on the opposite side of the processing gas supply pipe 124 from the side where the processing gas supply pipe 124 is installed. It is configured to be able to pull.

Further, as shown in FIG. 19, a focus ring 1 made of quartz surrounding the wafer W is placed on the upper surface of the susceptor 123 on which the wafer W to be processed is placed.
30 is provided so as to be higher than the processing surface of the wafer W. The focus ring 130 has the effect of concentrating the plasma generated on the susceptor 123 on the surface to be processed, thereby increasing the rate of processing, for example, etching. In addition, the focus ring 130 is provided on the susceptor 12 made of aluminum by the plasma.
The exposed portion that is not covered by the object 3 is etched,
It also has the effect of preventing generation of dust.

Further, an electrostatic chuck 132 is provided on the workpiece holding surface of the susceptor 123. The electrostatic chuck 132 is formed by bonding a conductor 131 such as a copper foil to an insulating film, for example, a polyimide resin by polyimide bonding. Even at a high temperature, for example, 100 ° C. to 150 ° C., the film does not peel off from the susceptor 123. , Has a function of accurately holding the wafer W to be processed. The electrostatic chuck 132 is connected to a power switch 134 via an electric wire 133.
Is connected to the DC power supply 13.
5 electrically grounded. This DC power supply 135
When a higher voltage, for example, 2 KV, is applied to the conductor 131 of the electrostatic chuck 132, the wafer W to be processed is
Is configured to be adsorbed and held.

Inside the susceptor 123, a temperature adjusting means for the object to be processed, for example, liquid nitrogen is supplied from a supply means (not shown) via a pipe 136, and a tank capable of temporarily storing liquid nitrogen. 137. The object to be plasma-processed by the temperature adjusting means is cooled, for example, on the susceptor 123 and maintained at a temperature suitable for the process, for example, a predetermined temperature of 0 ° C. to −150 ° C. during the process. An apparatus suitable for processing depending on the temperature of the processing object, for example, etching, ashing, film formation, and the like can be provided. In particular, in the etching of semiconductor wafers,
0.3μ by forming contact holes of 64M memory or more
m or less requires fine processing, and the technique of protecting the side wall of the contact hole with the reaction product of the processing gas and etching the bottom surface involves cooling the semiconductor wafer to a low temperature, for example, -100 ° C. or less. Must be processed.

A supply port 139 of the gas supply pipe line 124 to the processing chamber 122 is diverted through a gas diffusion plate (not shown), and a supply port of the processing chamber 122 has a porous gas diffusion shower head. For example, glassy carbon obtained by carbonizing a chlorofluorocarbon resin or a phenolic resin is provided. This gas supply port made of glassy carbon enables a uniform processing gas to be supplied to the object placed on the susceptor 123, and a processing result, for example, a high uniformity within the processing surface of the etching processing can be obtained. It is configured to be able to.

As is apparent from FIG. 20, the center of the top wall surface of the processing chamber 122 is cut out in a substantially circular shape, and a disk-shaped insulating member 128 is hermetically attached thereto. The material of the insulating member 128 is not particularly limited as long as it is an insulating member such as quartz glass or a ceramic material.
The light emission state of the plasma in the processing chamber 2 can be visually recognized.

A loop antenna 129 and a pole material 140 are mounted and fixed on the upper surface of the insulating member 128, that is, outside the processing chamber 122. The loop antenna 12
9 can be made of a conductive material such as a copper wire or a copper tube, but it is preferable to use a copper tube having excellent cooling characteristics. In this embodiment, as is apparent from FIG. 20, the loop antenna 12 that draws a one-turn loop is used.
9 is used, but is not limited to the illustrated example as long as a rotating electric field can be formed in the processing chamber by applying a high-frequency current.

For example, various types of antennas shown in FIGS. 4 and 8 can be used.
The connection configuration of the high frequency power supply and the capacitor shown in FIG. 8 can be adopted. Moreover, by configuring the antenna, the connection of the high-frequency power supply, and the like as described above, as described in the corresponding part, the plasma density can be made uniform and more uniform plasma processing can be performed. .

The loop antenna 129 is connected to a first high-frequency power source 142 via a matching box 141.
It is configured such that a high-frequency current can be applied from the Then, according to a command from the controller 143,
For example, by applying a high-frequency current of 13.56 MHz to the loop antenna 129, the insulating member 128
, A rotating electric field is formed in the processing chamber 122 to accelerate electrons and satisfy plasma generation conditions.

As the magnetic pole material 140 provided on the insulating member 128, it is preferable to use nickel zinc-based soft ferrite having low conductivity. When a magnetic pole material having high conductivity is used, an eddy current is generated by an alternating magnetic field generated when a high-frequency current is applied, and a desired magnetic field may not be formed in the processing chamber 2.

Regarding the shape of the magnetic pole material 140,
In the case of the illustrated embodiment, the periphery is made thicker and thinner at the center to achieve in-plane uniformity of the plasma density distribution in the processing chamber 122. However, as will be described later, the shape of the magnetic pole material 140 is reduced. Can be appropriately determined according to the processing conditions.

The horizontal cross-sectional area of the pole material 140,
That is, the cross-sectional area of the processing surface of the wafer W, which is the object to be processed, in the processing chamber 122 is configured to be larger than the area of the processing surface of the wafer body W when cut along a substantially horizontal plane. . With this configuration, it is possible to apply a magnetic field generated by the magnetic pole material 140 over the entire processing surface of the wafer W to be processed, and it is possible to more precisely control the plasma density distribution.

When a high-frequency current is applied to the loop antenna 129 to generate plasma, a demagnetizing field is generated in the magnetic pole material 140, which may adversely affect the magnetic field generated by the magnetic pole material 140. Therefore, according to the present invention, the above problem is overcome by providing the magnetic pole material 140 with a thickness that can ignore the influence of the demagnetizing field, or by devising a longer magnetic path.

A second high-frequency power supply 145 is connected to the susceptor 123 via a matching box 144. In response to a command from the controller 143, a high-frequency bias potential is applied during the etching process to the susceptor 123.
3. The susceptor 123 is separated from the processing chamber 122 by an insulator 138.
Are configured to be insulated from each other.

Further, according to this embodiment, the processing chamber 12
Magnetic field forming means, for example, permanent magnets 146a and 146b are arranged so as to surround the two side walls. As shown in detail in FIG. 21, the magnetic field forming means 146 is composed of a plurality of permanent magnets 146a, 146b, etc. arranged alternately in a ring with different polarities. Are formed. By the action of the multi-pole magnetic field, the plasma flow which is going to collide with the inner wall of the processing chamber 122 is pushed back to the center of the processing chamber 122, and the plasma is shaped and held near the processing surface of the wafer W which is the object to be processed. Is configured to be possible.

The plasma etching apparatus 121 according to the sixth embodiment is configured as described above. Next, its operation will be described.
A wafer W, which is an object to be processed, transferred from a cassette chamber (not shown) to a load lock chamber (not shown) by a suitable transfer means, for example, a transfer arm, is transferred from the load lock chamber to a gate valve 147 provided on a side surface of the processing chamber 122. 20 (see FIG. 20). Further, the wafer W is previously stored in a reduced pressure atmosphere, for example, 10 ⁻⁶ Torr.
r, is transferred into the processing chamber 122, and the susceptor 1
It is attracted and held by the electrostatic chuck 132 on 23.

Next, a wafer W, which is an object to be processed, is supplied through a gas supply pipe 124 provided at a shoulder of the processing chamber 122.
A predetermined process gas for performing plasma etching, such as Cl ₂ or CHF _3, is introduced into the processing chamber 122. At this time, the pressure in the processing chamber 122 is, for example, 10
^-3 Torr.

When performing the plasma etching,
From the first high frequency power supply 142 to the matching box 141
, A high frequency current of 13.56 MHz, for example, is applied to the loop antenna 129. The high-frequency current forms a magnetic field that moves up and down in the processing chamber 122 in the vertical direction, and a rotating electric field is formed around the magnetic field. The electrons are accelerated to the plasma potential by the rotating electric field, and plasma is formed in the processing chamber 122. In this case, according to this embodiment, a very uniform rotating electric field can be formed by the loop antenna 129, and therefore, a highly uniform plasma can be formed in the processing chamber 122.

Further, a magnetic field forming means 146 constituted by a plurality of permanent magnets 146a and 146b as shown in FIG. 3 is arranged around the processing chamber 122 of the plasma etching apparatus 121 shown in FIG. It is possible to push back the plasma flow which is going to collide with the inner wall of the processing chamber 122 to the center of the processing chamber 122 and to shape and hold the plasma near the processing surface of the wafer W as the processing target. Therefore, a uniform etching process can be performed on the processing surface of the wafer W that is the processing target.

In the plasma device 121 according to the present embodiment, the second high frequency power supply 145 is connected to the susceptor 123. Since the second high-frequency power supply 145 can be controlled independently of the first high-frequency power supply 142 for generating plasma, the high-frequency bias potential between the generated plasma and the susceptor 123 or the wafer W can be controlled. Can be adjusted freely. Therefore, by appropriately applying a high-frequency bias according to the processing gas or gas pressure to be used, it is possible to accelerate ions in the plasma flow and to make the ion flow uniform.

When the processing of the wafer W in the processing chamber 122 is completed as described above, the exhaust pipe 126 is opened, and the processing chamber 1 is exhausted by an exhaust system 127 such as a vacuum pump.
After sufficiently exhausting the residual processing gas and reaction products in the processing chamber 22, the gate valve 147 provided on the side surface of the processing chamber 122 is opened, and the wafer W on the susceptor 123 is moved by the transfer arm (not shown). The process is completed by unloading to a load lock chamber (not shown).

Next, referring to FIGS. 22 and 23,
The structure and operation of the soft ferrite, which is a magnetic pole material configured based on this embodiment, will be described. Generally, the density distribution of the plasma in the processing chamber 122 is affected by the magnetic field distribution in the processing chamber 122. Therefore, according to the present embodiment, in order to adjust the magnetic field distribution in the processing chamber 122, the magnetic material 1 such as soft ferrite is placed on the upper surface of the insulating member 128.
By arranging 40 and changing its shape, the magnetic field distribution in the processing chamber 122 can be adjusted, and the plasma density distribution can be freely adjusted.

However, according to this embodiment, in order to control the plasma density distribution over the entire processing surface of the wafer W, the horizontal sectional area of the magnetic pole material 140, that is, the processing surface of the wafer W is substantially It is important that the area of the cross section cut by the parallel plane is larger than the area of the processing surface. Further, as described above, when a high-frequency current is applied to the loop antenna 129, a demagnetizing field is generated in the magnetic pole material 10. Therefore, it is important that the magnetic pole material 0 has a thickness such that the effect can be ignored.

After satisfying the above conditions, the magnetic pole material 14
The density distribution of the plasma in the processing chamber 122 can be freely adjusted by appropriately adjusting the shape of the soft ferrite constituting the zero. For example, in the example shown in FIG. 19, when the magnetic pole material 140 is not installed, it is assumed that the density distribution around the plasma is lower than the center density distribution of the plasma, and when it is desired to make the plasma uniform,
As shown in the figure, by making the peripheral portion thicker than the central portion in the longitudinal cross section of the magnetic pole material 140 or by making the magnetic path longer, the plasma can be made uniform.

Since the required plasma density distribution depends on factors such as the type of the object to be processed, the reactive gas and the gas pressure, the shape of the magnetic pole material 140 is appropriately adjusted according to the present invention. This makes it possible to obtain a desired optimum plasma density distribution.

For example, in the example of FIG. 22, by completely covering the periphery of the loop antenna 129 ′ with the magnetic pole material 140 ′, the influence of the demagnetizing field generated by applying a high-frequency current to the loop antenna 129 ′ is canceled. In addition, it is possible to reinforce the magnetic field over the entire processing surface of the wafer W to be processed.

In the example shown in FIG. 23, the magnetic material 140 ″ made of soft ferrite is provided around the loop antenna 129 ″.
To offset the above-mentioned effect of the demagnetizing field, and to promote uniformization of plasma in the processing chamber 122 by making the central portion of the magnetic pole material 140 ″ thinner than the surroundings. it can.

Finally, in the example of FIG.
Although the structure of the loop antenna 129 is shown as a simple structure having a one-turn loop, the structure of the loop antenna 129 generates a good rotating magnetic field by applying a high-frequency current.
It is only necessary to be able to be formed inside, and it is not limited to the above example. For example, as shown in FIG. 24, it is also possible to form a loop antenna 149 in which one-turn loops are superposed and arranged to enhance the rotating magnetic field. In addition, it is also possible to use a spiral loop antenna having a loop of several turns to form a rotating magnetic field over a wide range.

In the above embodiment, the supply of the processing gas is performed, for example, on the upper surface of a chamber or a processing chamber as shown in FIGS.
6, the shower head 150 shown in FIG.
You may comprise so that it may supply from this shower head 150. The shower head 150 is made of, for example, an insulator such as fused silica, quartz, or ceramics, and has a gas inlet 151 and a buffer chamber 152 therein.
The back surface has a large number of discharge holes 153. The processing gas supply pipe 154 is connected to the gas inlet 151.

When the shower head 150 having such a configuration is used, the processing gas introduced from the gas inlet 151 into the buffer chamber 152 is once blocked there, and then is discharged from the respective discharge holes 153 at a uniform pressure and flow rate. Discharged or injected into the processing chamber. Therefore, this shower head 5
By using 0, the processing gas is uniformly supplied into the processing chamber and the chamber, so that the plasma density can be made more uniform.

Although the plasma apparatus according to the present invention has been described based on the embodiments, the plasma apparatus according to the present invention is not limited to the above embodiments, but includes an ashing apparatus,
The present invention can be applied to a sputtering device, an ion implantation device, a plasma CVD device, and the like. Also, the object to be processed can be applied to various types of plasma apparatuses that perform processing of an LCD substrate, for example. In this case, the form of the guide member and the antenna means of the guide means may be configured in accordance with the plane form of the substrate. For example, when the LCD substrate has a rectangular shape, the loop-shaped guiding member and the antenna means may be formed in a so-called rectangular loop shape from a linear or tubular conductive material. Also, the spiral form may be formed into a so-called rectangular spiral shape that is sequentially bent inward at a right angle. With this configuration, the same operation and effect as those of the above-described embodiments can be obtained for a rectangular object to be processed, and the object can be uniformly plasma-processed.

[0137]

According to the present invention, it is possible to displace the generation region of the generated plasma, which was utilized by changing the distribution of plasma density Ri can der be made uniform plasma In addition, it is possible to perform a plasma process with excellent uniformity on the object to be processed.

[0138] It is also allowed <br/> ability control of a wide plasma density or is found, it is possible to apply an excellent plasma treatment more uniform properties in the object to be processed. And, in the case where induction member is configured to control each independently of the high-frequency power supplied to each guide member in some cases more than one, can be adjusted, the strength of the alternating electric field induced by the individual guide member Therefore, it is possible to control the plasma density in a very fine and wide range.

[0139]

According to the third aspect , even if a permanent metal member is not used, the number of magnetic fluxes penetrating the center portion in the vertical direction is reduced, the intensity of the induced alternating electric field is reduced, and the plasma generation region is reduced. Since it is displaced outward in the radial direction, it is possible to use this to make the plasma density uniform.

Further , according to the present invention , it is possible to make the alternating electric field induced relatively sparse and dense between the outer part and the central part, and to make use of this to make the plasma density uniform. It has become.

[0142] Also it is possible to further accelerate the ions in the flop plasma, for example in an etching process,
The etching rate can be improved.

[0143] On the other hand, according to claim 6, also to reduce the magnetic flux density of the static magnetic field formed in a direction perpendicular to the alternating electric field by said antenna means, it is possible to achieve the ECR condition, the first for the The size of the magnetic field forming means can be reduced. In addition, since a small magnetic field is necessary for achieving the ECR condition, the influence of the diverging magnetic field on the plasma flow can be minimized. Since the second magnetic field forming means is provided so as to surround the processing chamber, the expansion region of the plasma flow introduced into the processing chamber is enlarged to a planar shape near the object to be processed, and a uniform plasma is formed in the processing region. While maintaining the flow, it is possible to direct the direction of the plasma flow perpendicular to the processing surface of the object to be processed.

[0144]

Further, according to the present invention , it is possible to further simplify and downsize the device.

[0146] it is possible to control the in addition the present invention further extensive plasma density, it is also possible to further improve the plasma uniformity.

According to the present invention , the conventional microwave ECR
Since the ECR condition can be achieved by using a much smaller high-frequency current than a plasma device, it is possible to reduce the size of a magnet for forming a required magnetic field, to maintain the magnet easily, and to improve the plasma. The apparatus itself can be reduced in size and simplified. In addition, since a small magnetic field is used as compared with the conventional apparatus, it is possible to minimize the influence of the divergent magnetic field generated in the processing chamber on the plasma flow, and to make the plasma flow more perpendicular to the processing surface of the object to be processed. It is possible to make the incident light.

[0148]

[0149]

[0150]

[0151]

[0162]

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a configuration of a first embodiment.

FIG. 2 is an explanatory diagram schematically showing a cross section showing the configuration of the first embodiment.

FIG. 3 is an explanatory diagram showing the operation of the first embodiment.

FIG. 4 is an explanatory plan view showing a loop antenna as another example of the antenna used in the first embodiment.

FIG. 5 is an explanatory plan view showing a spiral antenna which is another example of the antenna used in the first embodiment.

FIG. 6 is an explanatory plan view of an antenna used in a second embodiment.

FIG. 7 is an explanatory plan view showing another antenna used in the second embodiment.

FIG. 8 is an explanatory plan view of an antenna used in a third embodiment.

FIG. 9 is an explanatory plan view showing another example of an antenna that can be used in the third embodiment.

FIG. 10 is an explanatory plan view showing another example of an antenna that can be used in the third embodiment.

FIG. 11 is a schematic longitudinal sectional view of a plasma device according to a fourth embodiment.

FIG. 12 is a schematic sketch of a plasma generation portion of the plasma device shown in FIG.

13 is a schematic cross-sectional view of a plasma generation portion of the plasma device shown in FIG. 11 cut in a horizontal direction.

14 is a schematic cross-sectional view of a plasma processing portion of the plasma device shown in FIG. 11 cut in a horizontal direction.

FIG. 15 is a schematic cross-sectional view showing another example of a gas introduction path to a plasma generation portion that can be used in the fourth embodiment.

FIG. 16 is a schematic cross-sectional view showing another example of a gas introduction path to a plasma generation portion that can be used in the fourth embodiment.

FIG. 17 is a schematic longitudinal sectional view of a plasma device according to a fifth embodiment.

18 is a schematic plan view of the plasma device shown in FIG.

FIG. 19 is a schematic longitudinal sectional view of a plasma etching apparatus according to a sixth embodiment.

20 is an explanatory plan view of the plasma etching apparatus shown in FIG. 19;

21 is an explanatory horizontal sectional view of a processing chamber portion of the plasma etching apparatus shown in FIG. 19;

FIG. 22 is a cross-sectional view of a main part of another example of the relationship between the loop antenna and the soft ferrite of the plasma etching apparatus according to the sixth embodiment.

FIG. 23 is a cross-sectional view of a main part of another example of the relationship between the loop antenna and the soft ferrite of the plasma etching apparatus according to the sixth embodiment.

FIG. 24 is a cross-sectional view of a principal part of another example of the relationship between the loop antenna and the soft ferrite of the plasma etching apparatus according to the sixth embodiment.

FIG. 25 is a perspective view showing an overview of a shower head that can be used in each embodiment of the present invention.

FIG. 26 is a bottom view of a shower head that can be used in each embodiment of the present invention.

FIG. 27 is a longitudinal sectional view of a shower head that can be used in each embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plasma apparatus 2 Chamber 3 Top wall 4 Mounting table 6 High frequency power supply 15 Gas supply source 18 Exhaust system 20 Antenna 21 High frequency power supply 24 Thin plate W Wafer

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-1-110734 (JP, A) JP-A-2-235332 (JP, A) JP-A-3-79025 (JP, A) JP-A-3-107 68773 (JP, A) JP-A-62-227089 (JP, A) JP-A-63-213345 (JP, A) JP-A 64-32634 (JP, A) JP-A-4-290428 (JP, A) International Publication No. 91/10341 (WO, A1) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01L 21/3065 C23F 4/00 H01L 21/205 H05H 1/46

Claims (14)

(57) [Claims] A processing chamber configured to perform plasma processing on an object to be processed on a susceptor; and a portion outside the processing chamber corresponding to the object to be processed provided through an insulator; An induction means for forming an induction electric field in the vicinity of the object to be processed by supplying high-frequency power; and a paramagnetic member arranged so that at least a part thereof overlaps the induction means. A plasma device comprising two or more guide members, each guide member having a single spiral shape, and each of the guide members being concentrically arranged. 2. A processing chamber configured to perform plasma processing on an object to be processed on a susceptor, and a portion outside the processing chamber corresponding to the object to be processed is provided via an insulator, and An induction means for forming an induction electric field in the vicinity of the object to be processed by supplying high-frequency power; and a paramagnetic member arranged so that at least a part thereof overlaps the induction means. A plasma apparatus comprising two or more guide members, each guide member having a single spiral shape and a single loop shape, and these guide members are arranged concentrically. 3. A processing chamber configured to perform plasma processing on an object to be processed on a susceptor; and a portion outside the processing chamber corresponding to the object to be processed provided through an insulator; An inducing means for forming an induced electric field near the object to be processed by supplying high-frequency power,
The plasma device is characterized in that the guiding means is constituted by a spiral guiding member having a space region in the center. 4. The plasma apparatus according to claim 3, wherein said guiding means is constituted by a spiral guiding member having a different pitch between an outer portion and a central portion. 5. The plasma apparatus according to claim 1, further comprising a high frequency applying means for applying a high frequency bias to the object to be processed. 6. A plasma processing unit comprising a plasma generating unit and a plasma processing unit, wherein a plasma flow generated by the plasma generating unit is introduced into a processing chamber of the plasma processing unit, and is mounted on a susceptor in the processing chamber. What is claimed is: 1. A plasma apparatus for performing plasma processing on a fixed object to be processed, wherein an antenna for forming an alternating electric field in said processing chamber through an insulating member by applying a high-frequency current to said plasma generating unit. Means, and first magnetic field forming means arranged to surround the plasma generating portion and form a static magnetic field in a direction perpendicular to the alternating electric field, and appropriately adjusting the alternating electric field and the static magnetic field. Thereby, an electron cyclotron resonance region is formed in the processing chamber, and the plasma cyclotron is disposed in the plasma processing section so as to surround the processing chamber and is introduced into the processing chamber. Second magnetic field forming means for shaping and holding the plasma flow with respect to the object to be processed is provided; the insulating member forms at least a part of a wall of the processing chamber; Consists of two or more antenna members arranged substantially parallel to the outer wall surface of the insulating member
Each antenna member is a spiral antenna.
A plasma device , wherein these are arranged concentrically . 7. A plasma processing unit comprising a plasma generating unit and a plasma processing unit, wherein a plasma flow generated in the plasma generating unit is introduced into a processing chamber of the plasma processing unit, and is mounted on a susceptor in the processing chamber. What is claimed is: 1. A plasma apparatus for performing plasma processing on a fixed object to be processed, wherein an antenna for forming an alternating electric field in said processing chamber through an insulating member by applying a high-frequency current to said plasma generating unit. Means, and first magnetic field forming means arranged to surround the plasma generating portion and form a static magnetic field in a direction perpendicular to the alternating electric field, and appropriately adjusting the alternating electric field and the static magnetic field. Thereby, an electron cyclotron resonance region is formed in the processing chamber, and the plasma cyclotron is disposed in the plasma processing section so as to surround the processing chamber and is introduced into the processing chamber. Second magnetic field forming means for shaping and holding the plasma flow with respect to the object to be processed is provided; the insulating member forms at least a part of a wall of the processing chamber; Configuration based on two or more antenna members arranged substantially parallel to the outer wall surface of the insulating member
Each antenna member consists of a spiral antenna and a loop antenna.
An antenna, wherein the antennas are arranged concentrically . 8. An object to be processed in a processing chamber is subjected to plasma processing.
A plasma apparatus for performing plasma processing, the plasma apparatus having a spiral shape for plasma generation provided outside the processing chamber.
And a first antenna disposed outside the first antenna
High-frequency power is supplied to the spiral second antenna for plasma generation, and the first and second antennas.
And a high frequency power supply for supplying power .
Plasma equipment. 9. The first antenna and the second antenna
Means that the terminal located inside and the terminal located outside
And the high-frequency power is supplied from each inner terminal
Is the wherein the plasma apparatus according to claim 8. 10. The high frequency power supply is one high frequency power supply.
The plasma device according to claim 8 , wherein the plasma device is shared . 11. The system according to claim 1, wherein said common use comprises a first antenna and a second antenna.
Power provided between the antenna and the high-frequency power supply.
Claims characterized by being performed by a distribution circuit
The plasma device according to claim 10. 12. The first antenna and the second antenna
Claims characterized in that the lengths are different8,
12. The plasma device according to any one of 9, 10, and 11. 13. wherein the first antenna and the second antenna, wherein the high-frequency power is supplied via a capacitor, according to claim 8, 9, 10, 11 or 12 Plasma equipment. 14. The method according to claim 8, wherein high frequency currents having different current values flow through the first antenna and the second antenna. The plasma device as described in the above.