JP2001220670A - Plasma sputtering system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plasma sputtering system by which a thin film of required components is deposited on a surface, and a high capacity material is produced by utilizing an electoron beam exciting plasma system and utilizing a solid target in place of gas as for a part of components. SOLUTION: In an electron beam exciting plasma system provided with a discharge chamber 1 and a process chamber 2 adjacent thereto via a bottleneck and installed with an accelerating electrode 21 and a sample stand 3, target 4 is arranged at the process chamber 2, reaction plasma is acted, and sputtering is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma sputtering apparatus, and more particularly to an apparatus for sputtering a target using an electron beam excited plasma generator and stacking sputtered particles on a sample surface.

[0002]

2. Description of the Related Art By depositing a substance on a surface of a substrate material or performing physical and chemical treatments, a material can be transformed into a new material or the characteristics of the material can be improved. As such a surface treatment method, there is a vapor deposition plating method including a physical vapor deposition method PVD and a chemical vapor deposition method CVD which have been developed as thin film manufacturing techniques. The vapor deposition plating method is widely used for electronic device parts, but recently, its application has been spread to coating of metals, alloys, and ceramics for heat resistance, corrosion resistance, wear resistance, and the like.

For example, Japanese Patent Application Laid-Open No. 3-240957 discloses that
It is disclosed that a hard amorphous carbon-hydrogen-silicon thin film layer is formed on the surface of an iron-based metal material to obtain a metal material having high hardness and a very low friction coefficient. The film forming method disclosed in the above publication is a plasma CVD method, in which a material to be treated is disposed in a vacuum vessel and discharged in a gas atmosphere mainly composed of a silicon compound gas and a carbon compound gas to generate a reaction gas plasma. The thin film layer is formed by depositing the components on the surface of the material to be processed maintained at the negative potential.

[0004] Also, Japanese Patent Application No.
No. 326218 discloses a technique for producing a high-performance material in which a silicon-containing diamond-like carbon is laminated as a thin film on a substrate using an electron beam excited plasma generator.

[0005] The electron beam excited plasma apparatus comprises a discharge chamber filled with a discharge plasma generated by converting an inert gas into a plasma, and a reactive gas that is accelerated by an electron beam extracted from the discharge plasma through a bottleneck by an acceleration electrode and accelerated. And a process chamber for producing various reactions. In the discharge chamber, a cathode, an intermediate electrode, and a discharge electrode are arranged. When a discharge voltage is applied between the cathode and the discharge electrode, thermions emitted from the cathode act on an inert gas supplied to the cathode portion to discharge. Since plasma is generated and the discharge chamber is filled, when an acceleration voltage is applied between the discharge electrode and the acceleration electrode,
Electrons are extracted from the discharge plasma in the discharge chamber, accelerated, and a large current electron beam is supplied to the process chamber.

Various material gases, such as silane gas and methane gas, are supplied to the process chamber as needed for the reaction process. The electron beam turns the reactive material gas into plasma, and the generated active species (radicals) are deposited on the substrate. Various plasma treatments are performed on the surface of the sample placed in the process chamber, for example, by depositing or bombarding ions in the plasma perpendicularly to the sample according to the difference between the plasma potential and the sample surface potential.

[0007] The method disclosed in Japanese Patent Application No. 10-326218 uses an electron beam excited plasma apparatus and performs a plasma CVD process using a mixed gas of a hydrocarbon such as methane (CH4) and silane (SiH4) as raw materials. An amorphous silicon carbide (a-SiC) film is formed as a base layer on a diamond-like carbon (DLC) film to form a coating layer with high hardness and high adhesion, and it is possible to obtain a high hardness and low friction material with extremely high efficiency. it can. The silane gas used in this disclosure method is highly toxic and highly dangerous, such as spontaneous ignition in the air. Therefore, strict handling is required by expensive equipment considering safety, and both equipment and operation costs are high. Problem.

A physical vapor deposition method PVD using a solid silicon compound instead of a silicon compound gas such as silane is a sputtering method. To form a silicon carbide film by a sputtering apparatus, a silicon carbide (SiC) target is used. In this case, the composition ratio of silicon and carbon is determined by the composition of the target. Therefore, a method of selecting an arbitrary composition or changing the composition during the process could not be adopted in order to obtain a more appropriate high hardness and high adhesion film.

In a conventional sputtering apparatus, when plasma is generated using a gas other than argon, the sputtering efficiency is reduced. Therefore, when an oxide film is required, a gas in which argon is mixed with oxygen is used. But,
The sputtering efficiency was not sufficient because the argon concentration on the target surface was low.

[0010] When a silicon target is set inside a conventional plasma CVD apparatus and the sputtering method is used together, when a film forming plasma such as a hydrocarbon gas is generated, the surface of the silicon target also has a DL.
As a result, a C film was formed, and sputtering was not successful, and it was difficult to supply silicon.

When a sputtering process is to be incorporated into a differentially pumped electron beam excited plasma apparatus, reactive plasma generated in a process chamber for differentially pumping does not contain components such as argon which can be used for sputtering. In addition, a reaction chamber suitable for sputtering must be separately prepared, and a differential pumping mechanism is required, and a separate sputtering chamber is provided, so that the entire apparatus becomes large and expensive. Furthermore, in the differentially pumped electron beam excited plasma, part of the accelerated electron beam loses energy in the acceleration space, and part of the electron beam directly flows into the acceleration electrode and does not contribute to plasma generation in the process chamber. There were problems that the plasma density in the reaction chamber could not be made sufficiently high and that the power supply capacity had to be increased. Thus, in the plasma CVD apparatus, the plasma CVD
Process and sputtering process could not be used together.

[0012]

Accordingly, an object of the present invention is to provide a thin film of a necessary component by using a solid target instead of a gas for some components in an electron beam excited plasma apparatus. An object of the present invention is to provide a plasma sputtering apparatus that produces a high-performance material by depositing it on a surface.

[0013]

In order to solve the above-mentioned problems, a plasma sputtering apparatus according to the present invention includes an electric discharge chamber and a process chamber adjacent to the discharge chamber via a bottleneck and having an accelerating electrode and a sample stage. In a beam-excited plasma apparatus, a target is arranged in a process chamber, and a reactive plasma is actuated to perform sputtering. The discharge plasma can be generated by a DC discharge or by radio frequency or microwave.

According to the plasma sputtering apparatus of the present invention, since the rare gas flows into the process chamber and mixes with the reactive plasma at the same time that the electron beam is extracted from the discharge plasma in the discharge chamber, the rare gas in the reactive plasma is removed. The ions collide with the target and bounce off the target material,
This flies onto the sample surface and deposits, and at the same time, the plasma action of the reactive gas introduced into the process chamber acts to process the sample surface. According to the present invention, a sputtering action is added to a conventional chemical vapor deposition CVD using a mixed gas, and a process in which active species generated by decomposing a gas are caused to collide with a sample surface at a low speed, and a sputter particle is sputtered at a high speed Collision processes can coexist. Therefore, the controllability of the film quality is expanded and various high-performance materials can be obtained.

Since the sputtering by plasma is particularly efficient when argon is used, the rare gas in the present invention is preferably argon gas. When a thin film is formed on the sample surface, surface treatment can be performed by using a reactive gas as a film forming gas having a desired composition. In particular, if a predetermined process is performed using a reactive gas as a hydrocarbon gas, diamond-like carbon (DL
C) A film can be formed to be a high hardness material. The hydrocarbon gas is particularly preferably any one of methane, ethane, propane, butane, acetylene, and benzene. For the purpose of forming a silicon carbide thin film, it is preferable that silicon is set as a target and the reactive gas is treated as a hydrocarbon gas.

The target may be arranged adjacent to the process side surface of the discharge electrode, and may be connected to a DC power supply or a high-frequency power supply, or may be connected to the discharge electrode. Further, the target may be formed in an annular shape, and the plasma may pass through the position of the axis. Further, the discharge electrode may also serve as the target. Note that the target is preferably provided at a position facing the sample.

Further, it is preferable to provide a mechanism capable of changing the active area of the target and the reaction plasma. Although a physical shutter can be used as the variable mechanism, it is also possible to provide an electromagnetic coil around the target and adjust the target with a magnetic field. Further, the target may be formed of a plurality of materials. Further, a plurality of targets may be provided in the process chamber. Further, a plurality of discharge chambers may be provided for one process chamber.

Further, in order to solve the above-mentioned problems, a second plasma sputtering apparatus according to the present invention is an apparatus for performing sputtering by a plasma of a reactive gas acting on a target in a process chamber. Is formed. In particular, the target may have a porous structure so that the rare gas is blown out from the inside. Also in the second invention, the reactive gas can be turned into plasma by an electron beam accelerated by an electron beam excited plasma apparatus or the like.

According to the plasma sputtering apparatus of the present invention, the rare gas present on the front surface of the target is turned into plasma and collides with the target to cause particles to fly out. Therefore, rare gas ions are used for sputtering regardless of the type of reactive gas. Therefore, the sputtering efficiency does not decrease. Note that it is preferable to use an argon gas having high sputtering efficiency as a rare gas. Also in the second invention, a high-quality silicon-containing diamond-like carbon thin film layer can be easily formed on the material surface.

According to the electron beam excited plasma generator of the present invention, even if the distance between the gun position and the surface of the sample table is not made large, uniform high-density plasma is generated over a wide area and has a large area. High-speed plasma processing can be performed on a sample. Further, it is possible to cope with a large square substrate or the like by adjusting the shape of the plasma. Further, by controlling the active species in the plasma, a thin film can be formed according to an arbitrary deposition schedule.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the plasma sputtering apparatus according to the present invention will be described below in detail with reference to the accompanying drawings.

[0022]

Embodiment 1 FIG. 1 is a structural diagram for explaining a first embodiment of the plasma sputtering apparatus of the present invention. Referring to FIG. 1, a plasma sputtering apparatus according to the present embodiment includes a discharge chamber 1 having a cathode 11, an intermediate electrode 12, and a discharge electrode 13, and a process chamber 2 having an acceleration electrode 21, a sample holder 3, and a target holder 4. It consists of. The discharge chamber 1 has a cathode chamber provided with a cathode 11 separated by an intermediate electrode 12, and the cathode 11 has a filament for emitting thermoelectrons. An inert gas such as argon gas Ar is supplied to the cathode chamber. The intermediate electrode 12 has a communication hole in the center so that an inert gas and electrons can flow into a space between the intermediate electrode 12 and the discharge electrode 13. Intermediate electrode 12
Is connected to the discharge electrode 13 via a resistor.

An inert gas plasma, that is, a discharge plasma, is generated by a discharge current flowing between the cathode 11 and the discharge electrode 13. The electrons are drawn out of the discharge plasma into the process chamber 2 through the communication holes provided in the discharge electrode by the acceleration voltage applied to the acceleration electrode 21 and accelerated.
A process gas is introduced into the process chamber 2 and turned into plasma by the accelerated electrons to form a reactive plasma 22. In addition, argon ions contained in the discharge plasma also rush into the process chamber 2 through the communication holes and are mixed into the reactive plasma 22. Note that the wall 23 of the process chamber 2 is grounded.

The sample holder 3 and the target holder 4 are opposed to each other at symmetrical positions with respect to a line connecting the discharge electrode 13 and the acceleration electrode 21. The sample holder 3 includes a heater 3
2 and has a structure in which a sample 31 can be placed and rotated or moved up and down. An RF power supply 33 is connected to the sample holder 3 so that an RF bias can be applied to the sample. Although the sample 31 is covered by a grounded sample cover 34, the distance between them is set so that plasma is not generated.

The target holder 4 has a target 41 disposed at a position facing the sample 31. The target holder 4 is connected to another RF power supply 43, so that an RF bias can be applied to the target 41 independently of the sample 31. it can. The target holder 4 has a cooling cavity 42 therein and is cooled by cooling water. The target 41 is also guarded by the grounded target cover 44, but the distance between the target and the cover is set so that plasma is not generated.

In the plasma sputtering apparatus of the present embodiment, ions in the low-gas-pressure, high-density plasma 22 collide with the target 41 and the sputtered atoms
And the film is formed. By using a reactive gas such as oxygen or nitrogen as the process gas, an oxide film or a nitride film can be generated. If an argon gas is supplied to the front surface of the target 41, the target surface becomes a rare gas atmosphere, so that the sputtering efficiency is increased. Further, even if the process gas is a film-forming gas, the sputtering can be continued and the plasma CVD and the sputtering process can be performed simultaneously without covering the target surface with the film.

FIG. 2 shows that the target material is made porous to form the target 41, a header space 45 is provided behind the target material, and argon gas is supplied. The argon gas is ejected from the target surface through a hole in the target 41. 2 shows an example of the target holder 4 configured as described above. With the configuration shown in the figure, the argon gas supply nozzle is arranged on the side surface of the target and is sprayed on the front surface. Can be covered by Further, even if the target is worn and its surface shape changes, the target surface can always be covered with the argon gas without adjusting the position of the nozzle.

The illustrated target holder can be used not only in this embodiment but also in a process using a conventional sputtering apparatus. In the conventional sputtering apparatus, for example, the sputtering and the chemical reaction were simultaneously performed using a mixed gas of oxygen gas and argon gas, so that there was a problem that the sputtering efficiency was low. However, by using the target holder shown in FIG. Argon gas is preferentially supplied to the surface to increase the sputtering efficiency and improve the film formation rate. The target holder shown in FIG. 2 is an existing parallel plate type RF sputtering apparatus, E
It can be applied to various sputtering devices such as a CR sputtering device and an EBEP sputtering device.

FIG. 3 is an enlarged view of the discharge section showing a case where an RF coil is wound outside the discharge section to prepare discharge plasma. An RF coil 14 is wound around a chamber formed between the intermediate electrode 12 and the discharge electrode 13, and an RF power source is connected to the RF coil 14.
, The plasma density inside the discharge part is increased, and the extraction current is increased.

[0030]

Test Example 1 Next, a test example in which a DLC film is formed on a substrate made of carburized and quenched steel by the plasma sputtering apparatus of this embodiment will be described. In general, the DLC film has poor adhesion to steel, so that an intermediate layer is often interposed in order to increase the adhesion to steel. In this test, an amorphous silicon carbide a-SiC film was formed on a carburized and quenched steel substrate in a thickness of 0.3 μm, and a DLC film was formed thereon in a thickness of 0.7 μm to form a multilayer structure. The structure shown in FIG. 2 using porous silicon as a sputtering target was used, an argon gas was used as a blowing gas, and methane was used as a film forming gas.

First, the substrate held by the sample holder is heated to 150 ° C. by a heater built in the sample holder to evaporate the surface adsorbed material, and then argon plasma is generated to sputter the substrate surface for 10 minutes. Washed. Next, methane plasma was generated, and at the same time, an RF bias was applied to the silicon target and the substrate to form an intermediate layer a-SiC film for 20 minutes. Next, a DLC film was formed for 60 minutes except for the RF bias applied to the silicon target.

In order to verify the performance of the manufactured sample,
A sample in which a-SiC film was formed on a substrate and then DLC film was formed by plasma CVD using a mixed gas of silane and methane, which is a conventional method, was produced. A scratch test and altitude measurement were performed on these samples. The scratch test uses a scratch tester from CSEM,
Loading was performed up to 100 N with a diamond indenter having a radius of 200 μm. For the altitude measurement, the dynamic hardness was measured with a load force of 40 kgf (about 400 N) using an Elionix thin film hardness tester.

As a result, the scratch peeling load of the sample according to the present embodiment was 18 to 24 N and that of the sample according to the conventional method was 17 to 25 N, and the dynamic hardness was 15.8 GPa for the sample of the present embodiment. And 16.2 GPa, which showed almost the same performance. As described above, it was proved that the plasma sputtering apparatus of this example can form a DLC film having almost the same performance as that of the conventional method. In this test example, since the argon gas layer was formed on the target surface using the porous target, the DLC film was not formed on the target due to the generation of methane plasma, and the film could be stably formed. did it.

[0034]

[Embodiment 2] FIG. 4 is a configuration diagram illustrating a second embodiment of the plasma sputtering apparatus of the present invention. In the second embodiment, a discharge electrode is formed of a target material so that both are used. A ring-shaped acceleration electrode is installed in the process chamber, and the sample holder is installed at a position facing the discharge chamber. Hereinafter, elements having the same functions as those in FIG. 1 will be omitted by giving the same reference numerals. Referring to FIG. 4, the plasma sputtering apparatus according to the present embodiment includes a discharge chamber 1 having a cathode 11, an intermediate electrode 12, and a discharge electrode 13, and a process chamber 2 having an acceleration electrode 21 and a sample holder 3. . The discharge electrode 13 also serves as a target. Process room 2
Inside, an annular acceleration electrode 21 is provided so as to surround the opening of the discharge chamber 1, and the sample holder 3 is provided at a position facing the discharge electrode 13.

When an argon gas is supplied to the discharge chamber 1 to generate a discharge plasma by a discharge current and an accelerating voltage is applied to the accelerating electrode 21, the electron beam is extracted from the discharge plasma, flows into the process chamber 2 and is accelerated. . Process room 2
The process gas introduced into the process plasma forms a process plasma by accelerating electrons, and argon ions are also mixed into the process plasma. The sample holder 3 can be rotated and moved up and down with the sample 31 placed thereon.
A bias can be applied.

In the plasma sputtering apparatus of this embodiment, the argon ions in the process plasma are accelerated and collide with the discharge electrode 13, and the sputtered atoms collide with the sample 31 to form a film. For example, when an acceleration voltage of 100 V is applied, a process plasma is generated by the electron beam accelerated to 100 V in the process chamber 2. At the same time, ions in the process plasma in the process chamber have an energy of 100 eV and collide with a target also serving as a discharge electrode to sputter. The particles sputtered out are activated in the plasma and collide with the sample to form a film. Therefore, there is no need to separately install an RF power supply for the target.

By using a reactive gas such as oxygen or nitrogen as the process gas, an oxide film or a nitride film of the target material can be formed. Even if the process gas is a reactive gas or a film forming gas, the discharge electrode 13
Since the inside of the bottleneck is an argon gas atmosphere, sputtering can be efficiently generated. Further, when argon gas is supplied to the front surface of the discharge electrode 13, the sputtering efficiency is increased because the target surface is in an argon gas atmosphere. In addition, by adjusting the area of action between the target and the plasma ions, the amount of the sputtered substance can be changed to control the composition of the thin film layer to be deposited. FIG.
FIG. 6 is an exploded view showing a shutter mechanism that adjusts the active area of the target and the plasma. This shutter mechanism fixes a disk 46 having an opening 47 on the front surface of the discharge electrode 13 serving also as a target, and has an opening 49 on the front surface thereof.
Is provided to form a shutter, and by changing the rotation angle of the rotating disk 48, the area where the target is exposed to the plasma is adjusted.

Note that a target material may be attached instead of forming the discharge electrode 13 with the target material. When the target material is attached, the discharge electrode 13
Since the material can be arbitrarily selected, the life of the apparatus is prolonged, and an appropriate target can be selected and replaced as needed, which is convenient. FIG. 6 illustrates various aspects of combining a target with the discharge electrode 13. FIG. 6A shows a state in which a cylindrical target 51 is attached to the surface of the discharge electrode 13 on the process chamber side. The target 51 has the same potential as the discharge electrode 13. By appropriately setting the target shape such as the length and inner diameter, the amount of generated sputtered particles can be adjusted by changing the active area of the plasma. FIG. 6B shows a state in which the target plate 52 is electrically attached to the surface of the discharge electrode 13 on the process chamber side at the same electric potential, and a ceramic liner 53 is provided on the inner surface of the narrow path of the discharge electrode 13 so that plasma does not act. Thus, the discharge electrode is prevented from being sputtered. This has the effect of preventing plasma contamination and extending the life of the discharge electrode 13. FIG. 6C shows the discharge electrode 13.
It is formed of the target material including the bottleneck part of the above. A ceramic plate 55 is adhered to the exposed surface of the discharge electrode 13 on the process chamber side to prevent the discharge electrode 13 from being sputtered.

FIG. 7 is a view showing an embodiment of a target in which the sputtering amount is adjusted independently of the discharge electrode 13. FIG. 7A shows a configuration in which a ring-shaped target 56 is provided on the process chamber side of the discharge electrode 13. The target 56 is selectively connected to a DC power supply or an RF power supply via a switch 58, and is guarded by a grounded target cover 57. According to the sputtering conditions, an arbitrary DC bias or RF bias can be applied independently of the discharge electrode 13 to adjust the amount of sputtering. FIG. 7B is a diagram showing an embodiment using a disk-shaped target 59 having a circulation hole at the center. Although the structure is simpler than the structure shown in FIG. 7A, it has the same function.

The working area of the target and the plasma is shown in FIG.
Instead of the mechanical shutter shown in (1), electromagnetic adjustment can also be performed using an electromagnetic coil. FIG. 8 is a view showing an example in which the first coil 61 is provided inside the discharge electrode 13 and the second coil 62 is provided outside the target 60. The first coil 61 functions to converge the electron beam to a bottleneck. The second coil 62 changes the current value and
By changing the shape of the plasma inside, the target 6
The amount of sputtering is adjusted by changing the degree of contact with zero. Further, the plasma sputtering apparatus shown in FIG. 9 is different from the apparatus shown in FIG. 4 only in that the discharge electrode 13 serving also as a target is constituted by a perforated plate and provided with a large number of flow holes. Since the bottleneck is formed on the entire surface of the discharge electrode 13, the entire target functions as a sputtering region. Therefore, it is possible to cope with a large area sample. The hole size, hole interval, and aperture ratio of the communication holes can be freely designed in consideration of the spread and uniformity of the plasma. For example, if the aperture ratio at the outer periphery is made higher than that at the inner periphery to supply more accelerated electrons and sputtered particles toward the outer periphery, the electrons diffuse as the distance increases and eventually increase. A process with a uniform area can be realized.

[0041]

Test Example 2 Next, DLC was applied to a carburized and quenched steel substrate by the plasma sputtering apparatus of this embodiment shown in FIG.
A test example when a laminated film of a film and a silicon-containing DLC film is formed will be described. Silicon-containing DLC has a very small coefficient of friction as compared with DLC, but has a disadvantage in that the amount of wear is large. However, the characteristics can be improved by laminating DLC and silicon-containing DLC. In this test example, the first
In the same manner as in the test example, the substrate and DLC were
Amorphous silicon carbide a-S to improve the adhesion of
An iC film was formed to a thickness of 0.3 μm, and a DLC / silicon-containing DLC laminated film was formed thereon to a thickness of 0.7 μm. Porous silicon was used as a sputtering target, argon gas was used as a blowing gas, and methane was used as a film forming gas.

Further, a shutter mechanism as shown in FIG. 5 is provided on the plasma chamber side of the target, and the rotary disk 48 on the front surface is swung to completely hide the target and to expose the entire opening. It occurred alternately.
First, the temperature of the substrate held by the sample holder was raised to 150 ° C. to evaporate adsorbed substances on the surface, and then the substrate surface was sputter cleaned with argon plasma for 10 minutes. Next, methane plasma is generated, and an RF bias is applied to the silicon target and the substrate while the shutter is open, so that the intermediate layer a-SiC
The film was formed for 20 minutes. Thereafter, the DLC / silicon-containing D
An LC laminated film was formed for 60 minutes.

Further, for comparison, a silicon-containing DLC film was formed with the shutter open. In order to compare the laminated film sample manufactured in Test Example 2, the DLC film sample manufactured in Test Example 1, and the sample of the silicon-containing DLC film, a friction and wear test was performed on these samples. Each sample was subjected to a ball-on-disk method without lubrication at a sliding speed of 0.1 m / s and a load of 2N,
It was slid for 00 rotations. The friction coefficient was measured during the test, and after the test, the sliding mark was swept with a step gauge to measure the friction depth.

As a result, the coefficient of friction was 0.052 for the laminated film sample of this test example, 0.11 for the DLC film sample, and 0.048 for the silicon-containing DLC film sample. In addition,
The coefficient of friction is a value after adaptation. The wear amount was 70 nm for the silicon-containing DLC film sample, but could not be detected for the laminated film sample and the DLC film. As described above, the DLC / silicon-containing DLC laminated film manufactured by the apparatus configuration of the present invention has a friction coefficient comparable to that of the silicon-containing DLC film while exhibiting wear resistance comparable to the DLC film.
It has been proven to have very high performance.

[0045]

Embodiment 3 A plurality of targets can be prepared when the composition needs to be changed during the deposition of the target material. FIG. 10 is a diagram showing an example in which a second ring-shaped target 63 is further provided on the plasma chamber side of the first ring-shaped target 56 provided on the front surface of the discharge electrode 13 and connected to independent power supplies. Independent DC bias or RF bias can be applied to each target, and the amount of sputtering can be adjusted. The composition of the deposited layer can be finely adjusted by adjusting the bias of the sample in accordance with each bias adjustment.

FIG. 11 is a view showing a configuration in which the degree of freedom in composition adjustment is further increased by dividing the target placed on the front surface of the discharge electrode into three parts and connecting independent power supplies to the three parts. The fan-shaped targets 64 are integrated with each other with the insulator 65 interposed therebetween to form a disk. Each sector 64 is connected to an independent RF power source 66 so that a bias suitable for each condition is applied at an appropriate timing. Each target particle sputtered by the rare gas ions in the process plasma is deposited on the surface of the substrate on the sample holder according to a program to become a target product. It goes without saying that the number of target divisions can be arbitrarily selected according to the required product.

[0047]

Fourth Embodiment FIG. 12 is a configuration diagram showing an example in which the present invention is applied to a ring-type electron beam excited plasma apparatus (RSEBEP). In RSEBEP, a part of a discharge chamber 1 that defines a discharge plasma region protrudes into a process chamber 2, and a discharge electrode 13 that is water-cooled is disposed in the protrusion 15, and discharge plasma fills the protrusion 15. . The ring-shaped accelerating electrode 2 is set at the height of the extraction hole formed in the side surface of the protrusion 15
1, an electron beam is extracted from an extraction hole, accelerated, and the reactive gas supplied to the process chamber 2 is turned into plasma to form a process plasma 22.

In the plasma sputtering apparatus of this embodiment, a ring-shaped target 4 is set on a process plasma 22 formed in a ring shape in a process chamber.
The target 4 is connected to an RF power source 43 to which an RF bias is applied, receives sputtering of argon ions in the process plasma 22, and scattered sputtered particles are placed on the sample holder 3 disposed below the process plasma 22. A film is deposited and deposited on the surface of the sample 31.

FIG. 13 is a drawing showing an RF coil 16 serving also as a function of the discharge electrode 13 provided in the protrusion 15 of the discharge region. Since the plasma density of the discharge part can be increased as compared with the case where the argon gas is converted into plasma only by the direct current, the extraction efficiency of the extraction beam can be increased. Further, since thermionic electrons can be supplied from the cathode 11 in accordance with the extraction of the electrons, the surface of the coil 16 is not consumed by sputtering.

FIG. 14 shows the RSE shown in FIG.
It is a drawing which shows various modes which produced discharge plasma only by RF discharge by RF electrode instead of DC discharge in BEP. FIG. 14A shows a case in which a vessel 18 made of quartz is inserted into the center of a region where discharge plasma is to be formed, and an RF coil 17 is charged therein to perform RF discharge. The RF coil 17 does not come into contact with the argon gas plasma. FIG. 14B shows the case where the RF coil 17 is directly inserted into the argon gas plasma generation region 19. FIG. 14 (c) shows an arrangement in which an RF coil 17 wound spirally with a quartz wall 20 interposed between ceilings of a discharge chamber. As described above, when the RF discharge is used, since the electrodeless discharge is used, there is no sputtering effect on the electrode, and there is no plasma contamination by the electrode material.

It is also possible to form the discharge plasma only by microwave discharge. FIG. 15 is a diagram showing a configuration of a discharge unit configured to extract electrons from a discharge plasma generated by a microwave through a bottleneck. In the discharge region of the electron beam excited plasma generator shown in the figure, a microwave source 71 such as a magnetron is coupled to a coaxial line including a center conductor 72 and an outer conductor 73. The end of the coaxial line on the atmosphere side is the center conductor 72 and the outer conductor 7.
3 is electromagnetically fixed by a short-circuiting device 74 that electrically short-circuits the circuit 3 and the other end thereof is fitted into the process chamber 2 to form a discharge chamber 75. A partition 76 made of an insulating material is provided outside the discharge chamber 75. Process room 2
Microwave discharge is performed in the discharge chamber 75 fitted in the inside, a discharge plasma is generated, and electrons can be extracted into the process chamber 2. An acceleration power supply is connected between the outer conductor 73 and an acceleration electrode provided in the process chamber, and the extracted electrons are accelerated by the applied acceleration voltage, and are accelerated.
The process gas inside is turned into plasma.

FIG. 16 is a drawing showing an example of the arrangement of targets when a plurality of targets are installed in a ring-type electron beam excited plasma apparatus. Discharge chamber protrusion 15
And four targets 77 are provided above a position of the process chamber 2 between the ring-type accelerating electrodes 21. The targets 77 are separated from each other by partition walls 78. The sample holder is set under the target 77, and the sample placed on the sample holder can be sequentially passed under each target 77 by a rotation mechanism to form a multilayer film. The superlattice film can be formed while suppressing the mixture between the film types by the partition walls 78 between the targets.

[0053]

[Embodiment 5] FIG. 17 is a sectional view showing another embodiment of the plasma sputtering apparatus of the present invention. This embodiment is a ring type electron beam excited plasma generator in which the outer wall of the process chamber is doubled to form a discharge chamber, a draw-out path is provided on the inner wall, and electrons are ejected toward the center of the process chamber. It is applied to In the plasma sputtering apparatus according to the present embodiment, the upper half wall of the process chamber 2 forms a double bell jar-shaped discharge chamber 1. The discharge chamber 1 includes a cathode chamber defined by the cathode 11 and the intermediate electrode 12, and a plasma chamber formed so as to cover the process chamber 2. At the bottom of the plasma chamber, a discharge electrode 13 is provided in an annular shape, and a disk-shaped auxiliary electrode 81 is provided on an extension of the axis of the intermediate electrode 12. On the inner wall of the discharge chamber 1, a number of draw-out paths are formed inward.

The process chamber 2 is provided with a sample holder 3 having a surface on which the sample 31 is placed in parallel with the direction in which electrons are drawn, and which can be rotated and moved up and down. Also, the sample holder 3
The accelerating electrode 24 is provided at substantially the same height. Further, a gas shower ring pipe 25 is provided in the process chamber 2 to introduce a process gas into a process plasma portion. The gas showering pipe 25 can move up and down in the process chamber 2 to adjust the showering position. A disk-shaped target 82 is arranged on the ceiling of the process chamber 2.

When a heating current is applied to the cathode 11, thermoelectrons are emitted to the surroundings. When an inert gas is supplied to the cathode chamber, the cathode 11 and the auxiliary electrode are mediated by an initial discharge generated between the cathode 11 and the intermediate electrode 12. Discharge occurs during 81. Next, when the auxiliary electrode 81 is disconnected from the discharge power source, the plasma further grows to the discharge electrode 13, and the discharge plasma from the cathode 11 to the discharge electrode 13 is stably present. Here, the accelerating voltage is the accelerating electrode 2
When the voltage is applied to the plasma chamber 4, a large current is extracted from the plasma in the discharge chamber 1 through the extraction path and flows toward the center of the process chamber 2.

On the other hand, the process gas introduced into the process chamber 2 is turned into plasma by the electron flow flowing from the surroundings. At this time, argon ions also flow into the process chamber 2 and mix into the process plasma. Argon ions in the plasma collide with the target 82 and the bounced target particles are deposited on the surface of the sample 31. At the same time, the plasma of the process gas is applied to the sample 3 on the sample holder 3.
Reacts with the surface of one to produce a product. When the process plasma is a reactive gas that reacts with the target particles, the target material that has undergone a chemical reaction acts on the sample surface.

[0057]

Embodiment 6 FIG. 18 is a view for explaining an example of a plasma sputtering apparatus in which a plurality of target holders are installed in a process chamber. Two target holders 4 are provided at positions facing the sample holder 3 provided in the process chamber 2.
Is installed. Each target can apply an independent bias, and is used for manufacturing a material having a laminated film.

[0058]

Seventh Embodiment FIG. 19 is a sectional view for explaining another embodiment of the plasma sputtering apparatus of the present invention. The present embodiment is a plasma sputtering apparatus provided with two electron beam guns provided with a target downstream of a discharge electrode. Using the plasma sputtering of this embodiment, multiple layers of thin films having different compositions can be formed on the sample surface. The plasma sputtering apparatus according to the present embodiment has electron beam guns 1 and 1 ′ at both ends of a process chamber 2, and has acceleration electrodes 21 and 21 ′ installed at opposing positions. The substrate holder 3 is disposed at a position sufficiently higher than the center axis of the electron beam generators 1 and 1 'in the center of the process chamber 2. The targets 4, 4 'are installed in front of the respective electron beam guns 1, 1', and each has an RF
The power supplies 43, 43 'are connected.

The argon gas supplied to the discharge chambers 1 and 1 ′ is ionized and included in the process plasma converted into a plasma by the electron beams emitted from the electron beam generators 1 and 1 ′. The sputtered particles collide with the targets 4 and 4 'provided on the front surface of 1' and sputter out. The sputtered particles act on the surface of the sample 31 as it is or in a state of chemically reacting with the process gas component. With this configuration, the density distribution of the process plasma 22 formed in the process chamber 2 becomes more uniform, and a more uniform thin film can be formed on the large-area substrate 31.

[0060]

As described in detail above, in the plasma sputtering apparatus of the present invention, a target is provided in or near the process chamber of the electron beam excited plasma apparatus, and rare gas ions in the process plasma collide with the target. Then, the particles are made to bounce off and act on the sample surface as sputtered particles. Therefore, the surface treatment can be performed by combining the conventional chemical vapor deposition and sputtering. With the apparatus of the present invention, a high quality material can be obtained by efficiently performing the surface treatment of the material.

[Brief description of the drawings]

FIG. 1 is a sectional view of a first embodiment of the plasma sputtering apparatus of the present invention.

FIG. 2 is a sectional view showing an example of a target holder structure used in the first embodiment.

FIG. 3 is a cross-sectional view illustrating an example of a discharge unit structure used in the first embodiment.

FIG. 4 is a sectional view of a second embodiment of the plasma sputtering apparatus of the present invention.

FIG. 5 is an exploded view illustrating an example of a target shutter mechanism used in the second embodiment.

FIG. 6 is a cross-sectional view showing various modes of combining a target with a discharge electrode.

FIG. 7 is a cross-sectional view showing an embodiment of a target independent of a discharge electrode.

FIG. 8 is a cross-sectional view illustrating an example of a method for adjusting the working area of the target and the plasma.

FIG. 9 is a configuration diagram showing an example in which a porous discharge electrode is also used as a target in the second embodiment.

FIG. 10 shows a third example in which a plurality of targets are used.
It is sectional drawing of the discharge electrode part which shows Example of (a).

FIG. 11 is a perspective view showing an example in which a target is a composite.

FIG. 12 shows a fourth example of the plasma sputtering apparatus of the present invention.
It is sectional drawing of an Example.

FIG. 13 is a sectional view showing an example of a discharge unit used in the fourth embodiment.

FIG. 14 is a cross-sectional view showing another example of the discharge unit used in the fourth embodiment.

FIG. 15 is a cross-sectional view showing still another example of the discharge unit used in the fourth embodiment.

FIG. 16 is a sectional view showing an example of the arrangement of targets in a fourth embodiment.

FIG. 17 shows a fifth example of the plasma sputtering apparatus of the present invention.
It is a lineblock diagram of an example.

FIG. 18 is a drawing for explaining a sixth embodiment of the plasma sputtering apparatus provided with a plurality of target holders.

FIG. 19 shows a seventh embodiment of the plasma sputtering apparatus according to the present invention.
It is a lineblock diagram of an example.

[Explanation of symbols]

1, 1 'Discharge chamber / electron beam gun 11 Cathode 12 Intermediate electrode 13 Discharge electrode 14 RF coil 15 Projection 16, 17, RF coil 19 Argon gas plasma generation area 20 Quartz wall 2 Process chamber 21, 24, 24' Acceleration electrode 22 Process Plasma 23 Process chamber wall 25 Gas shower pipe 3 Sample holder 31 Sample 32 Heater 33 RF power supply 34 Sample cover 4, 4 'Target holder 41 Target 42 Cooling cavity 43, 43' RF power supply 44 Target cover 45 Header space 46 Fixed disk 47,49 Opening 48 Rotating disk 51,52,56,59,60,63,64 Target 53 Ceramic liner 55 Ceramic plate 58 Switch 57 Target cover 61,62 Coil 65 Insulator 66 RF power supply 71 Microwave source 72 center conductor 73 the outer conductor 74 short 75 discharge chamber 76 partition wall 77 target 78 partition wall 81 auxiliary electrode 82 target

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4K029 AA01 AA24 BA34 BA56 CA06 DC03 DC13 DC16 DC32 DC34 DC35 5F045 AA08 AA09 AA14 AA19 AB06 AB07 AC01 AF10 BB14 DA52 EB15 EE07 EF18 EH09 EH11 EH18 5F103 AA09 ABB DD BB RR05

Claims (22)

[Claims] 1. A discharge chamber filled with discharge plasma formed from a rare gas, and a process chamber formed adjacent to the discharge chamber through a bottleneck, and an acceleration electrode and a sample are placed in the process chamber. A sample stage is provided, and electrons are extracted from the discharge plasma in the discharge chamber into the process chamber through the bottleneck by the accelerating electrode, accelerated, and the gas in the process chamber is turned into a reactive plasma to act on the sample surface. A plasma sputtering apparatus, wherein a target for performing sputtering by reacting a reaction plasma in the process chamber is provided in the process chamber. 2. The plasma sputtering apparatus according to claim 1, wherein said discharge plasma is generated by a DC discharge. 3. The electron beam according to claim 2, wherein the discharge chamber includes a cathode, an intermediate electrode, and a discharge electrode, and the discharge plasma is generated by a discharge generated between the cathode and the discharge electrode. Excited plasma generator. 4. The plasma sputtering apparatus according to claim 1, wherein said discharge plasma is generated by high frequency or microwave. 5. The plasma sputtering method according to claim 1, wherein the target is disposed adjacent to a surface of the discharge electrode on a process chamber side, and is connected to a DC or high-frequency power supply. apparatus. 6. The device according to claim 1, wherein the target is disposed adjacent to a surface of the discharge electrode on the process chamber side, and is placed at the same potential as the discharge electrode. Plasma sputtering equipment. 7. The plasma sputtering apparatus according to claim 1, wherein the target has an annular shape, and the plasma accelerated in the inside diameter passes therethrough. 8. The plasma sputtering apparatus according to claim 1, wherein the discharge electrode is formed of a sputtering material and also serves as the target, instead of the target being provided in the process chamber. Plasma sputtering equipment. 9. The plasma sputtering apparatus according to claim 1, wherein the target is installed at a position facing a sample in the process chamber. 10. The plasma sputtering apparatus according to claim 1, further comprising a mechanism for changing an area on which the target and the reaction plasma act. 11. The plasma sputtering apparatus according to claim 10, wherein said mechanism comprises an electromagnetic coil provided around said target. 12. The plasma sputtering apparatus according to claim 1, wherein the target is made of a plurality of materials. 13. The plasma sputtering apparatus according to claim 1, wherein a plurality of said targets are provided. 14. The plasma sputtering apparatus according to claim 1, wherein a plurality of said discharge chambers are provided. 15. A plasma sputtering apparatus comprising a process chamber, a target for performing sputtering installed in the process chamber, and introduction of a reactive gas into the process chamber to form plasma and act on the target. A rare gas film is formed on the front surface of the plasma sputtering apparatus. 16. The plasma sputtering apparatus according to claim 15, wherein the target has a porous or porous structure, and is configured to blow out a rare gas from the inside. 17. The method according to claim 1, wherein said reactive gas is turned into plasma by an accelerated electron beam.
17. The plasma sputtering apparatus according to 5 or 16. 18. The plasma sputtering apparatus according to claim 1, wherein the rare gas is an argon gas. 19. The plasma sputtering apparatus according to claim 1, wherein said reactive gas is a film forming gas. 20. The plasma sputtering apparatus according to claim 19, wherein said film forming gas is a hydrocarbon gas. 21. The hydrocarbon gas is methane, ethane,
21. The plasma sputtering apparatus according to claim 20, wherein the apparatus is any of propane, butane, acetylene, and benzene. 22. The plasma sputtering apparatus according to claim 20, wherein the target is silicon.