JPH1143767A - High frequency ion bombarding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a high frequency ion bombarding device high in the evaporat ing rate of evaporating material, furthermore giving sufficient ion bombarding action to the face to be vapor-deposited, moreover feeding stable high frequency electric power even to the body to be treated having a complicated shape and capable of forming dense vapor-deposited film. SOLUTION: The inside of a vacuum tank 1 is separated into an evaporating space at the inside and a plasma space part at the outside by a discharge shielding and vapor deposition correcting mask 12, so that the increase of the vapor depositing rate and the improvement of plasma density are made consistent with. As for the body 9 to be treated, by its rotation, vapor deposition and ion bombardment are repeatedly executed, but, by adjusting the width of the opening part, the ion bombarding time to the vapor-depositing time can longly be taken. Furthermore, the opening of the discharge shielding and vapor deposition correcting mask 12 functions as a vapor deposition correcting board.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ion generating and impacting device in a vacuum, and more particularly to an ion generating and impacting device suitable as an ion plating device for applying high frequency power.

[0002]

2. Description of the Related Art Conventionally, in an ion plating apparatus or the like using a vacuum vessel into which an active gas or an inert gas, or a mixed gas thereof is introduced, an evaporation source of a deposition material and an object to be processed are placed in the same vacuum vessel. It is common to arrange them together. However, in such a configuration, if the degree of vacuum in the container is increased, the evaporation rate of the deposition material can be kept high, but a sufficient ion bombardment effect cannot be obtained due to a decrease in the number of ions generated by high-frequency discharge. . Also, the chemical reaction between the evaporating substance and the atmospheric gas becomes insufficient, for example,
Oxygen atmosphere makes it difficult to form a metal oxide film. Conversely, if the gas pressure in the vacuum vessel is increased, the plasma density will increase and the ion bombardment effect will increase,
It reduces the evaporation rate of the deposition material and lowers the productivity.

Further, when a substrate having a large effective area is rotated for uniform processing, it is difficult to supply power due to poor contact due to the rotation, and it has been difficult to maintain stable plasma. On the other hand, even if the discharge electrode serving also as the substrate support is made to perform a movement such as rotation, it is possible to supply a stable high-frequency power without interruption and to give an effective ion bombardment effect to the substrate. It has been proposed to provide an auxiliary electrode for supplying high-frequency power in the same vacuum vessel (Japanese Patent Publication No. 5-20857).
issue). However, this case has been developed for the case where a flat substrate, a convex or concave lens, or various curved reflectors revolve or revolve on a horizontal orbit. Also in the present invention, the evaporation source and the substrate to be deposited are arranged in the same vacuum vessel, and the advantages and disadvantages due to the degree of vacuum in the vessel are the same as described above.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a high-frequency ion bombardment apparatus capable of exerting a sufficient ion bombardment action on a surface to be deposited while always keeping the evaporation rate of a deposition substance high. Things. Furthermore, even for a workpiece having a complicated shape such as a cylinder, a sphere, and a spheroid, a stable high-frequency power is supplied, and a dense vapor deposition film can be formed. It aims at obtaining an ion bombardment device.

[0005]

According to the high frequency ion bombardment apparatus of the present invention, the inside of the vacuum chamber is substantially divided into an evaporation chamber and an ion bombardment chamber. The processing body, its support, and an auxiliary electrode for applying high-frequency power to the support are arranged, and an atmospheric gas is introduced from the ion bombardment chamber into the vacuum chamber. Substantially dividing the inside of the vacuum chamber into an evaporation chamber and an ion bombardment chamber is a discharge shielding plate disposed between the evaporation source and the object to be processed,
It is desirable that this discharge shielding plate also serves as a correction plate for vapor deposition.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 2 shows a basic structure of a high-frequency ion bombardment apparatus according to the present invention. An evaporation source 26 and an object to be processed 29 are arranged in the vacuum chamber 21, and the object to be processed 29 is cylindrical in the illustrated example, and rotates around a shaft 30. The high-frequency power passes from a high-frequency power supply 23 through a matching circuit 24, via a coiled auxiliary electrode 25 in the vacuum chamber 21,
Is applied to In the present invention, the inside of the vacuum chamber 21 is substantially divided into an evaporation chamber 34 and an ion bomb chamber 35 by a grounded discharge shielding plate 32, and the plasma generated by the coiled auxiliary electrode 25 fills the ion bomb chamber 35 completely. Although it spreads, it does not spread to the evaporation chamber 34. For example, an atmosphere gas such as an active gas such as oxygen, an inert gas such as argon, or a mixed gas thereof is introduced into the ion bomb chamber 35 through the adjustment valve 22. 36 is an adjusting member for adjusting the width of the opening 37 of the shielding plate 32, and 38 is an exhaust port.

In the high-frequency ion bombardment apparatus having such a configuration, when an atmosphere gas is introduced through the adjustment valve 22 while evacuating from the exhaust port 38, the atmosphere gas pressure in the ion bombardment chamber 35 is reduced by the opening 37 of the discharge shielding plate 32. Due to the small size, the pressure in the evaporation chamber 34 is kept higher.
When the evaporation source 26 is heated while rotating the processing target 29, the evaporation substance is deposited on the surface of the processing target 29 through the opening 37 of the discharge shielding plate 32, but is deposited only at the position facing the opening, and is oblique. Is cut off by the shield plate, so that the shield plate 32 simultaneously acts as a vapor deposition correction plate. Here, the coil-shaped auxiliary electrode 2 is
When high-frequency power is applied via 5, the plasma spreads in the ion bombardment chamber 35, the object 29 is negatively charged, and the entire surface thereof is bombarded by ions. Workpiece 2
The surface of the substrate 9 is vapor-deposited when facing the opening 37. If the surface of the substrate 9 deviates from the opening position by rotation, it is subjected to ion bombardment while returning to the opening position again. In the meantime, the film is oxidized and becomes more dense at the same time. And the evaporation chamber with low atmospheric gas pressure not only facilitates the evaporation from the evaporation source, but also reduces the energy loss of the evaporated steam, and as a result,
A decrease in hardness and density of the film can be prevented. On the other hand, in the ion bombardment chamber 35, the plasma density can be increased by the relatively high atmospheric gas pressure, and the ion bombardment effect can be enhanced.

The high-frequency ion bombardment device having the above-described basic configuration can be implemented in various modes. That is, the processing target 29 may have a flat processing target surface extending in parallel with the discharge shielding plate 32, and move relatively parallel to the opening 37. Further, as shown in the embodiment, a reciprocating support, a cylindrical object to be rotated, or an object to be processed having a shape in which film formation is effectively performed by rotating, may be disposed together with the discharge shielding plate, Alternatively, various embodiments can be adopted, such as rotating a flat plate having a surface to be processed extending in the circumferential direction of the support base outside the fixed discharge shielding plate.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, as an embodiment of the present invention, an object to be processed having a complicated shape such as a cylinder, a sphere, a spheroid and the like, made of quartz, glass, ceramics, metal or the like, which has been difficult in the past, will be described. On the other hand, a high-frequency ion bombardment apparatus that enables stable processing to be performed on a plurality of objects to be processed is shown. FIG.
, 1 is a vacuum chamber, 2 is an atmosphere gas introduction adjusting valve, 3 is a high frequency power supply, 4 is a matching circuit, 5 is an auxiliary electrode, 6
Denotes an evaporation source, and a support 10 that rotates by each axis is provided on a support 8 of the object to be processed that is rotated by a shaft 11.
A large number of objects to be processed 9 are fixed to the substrate. A discharge shielding plate and a vapor deposition correction mask 12 are fixed to the support base 8 via an insulator 7.
Revolves with the support 8. Reference numeral 13 denotes a quartz film thickness gauge.

While the inside of the vacuum chamber 1 is evacuated by a vacuum pump (not shown), an appropriate pressure is maintained by appropriately introducing atmospheric gas from an atmospheric gas introduction adjusting valve 2. On the other hand, high-frequency power is applied by mechanical contact from the high-frequency power supply 3 to the holding member 10 on the rotating support base 8 via the matching circuit 4 and the auxiliary electrode 5. A plasma of the introduced gas is generated, and an induced negative bias voltage is generated in the holder 10. The discharge shielding plate and evaporation correction mask 12 is electrically grounded, and has a function of shielding plasma generated by high-frequency discharge from the inside of the shielding plate. Further, the introduced gas is also introduced into the plasma portion, and the flow of the gas is different between the inside and outside of the discharge shielding plate and the evaporation correction mask 12 having a small opening amount, and a pressure difference is generated. Therefore, increasing the plasma density in the plasma space and increasing the ion bombardment effect without reducing the evaporation rate of the evaporation source is as described with reference to FIG. In addition, the opening of the discharge shielding plate and the evaporation correction mask 12 functions as an evaporation correction plate by limiting the incident angle of the evaporated vapor incident on the processing target 9.

The film deposited on the object 9 is
With this rotation, the ion beam moves from the front of the opening, and receives only ion impact continuously until it returns to the front of the opening once. For this reason, the deposition-ion bombardment-deposition-ion bombardment is repeatedly performed on the surface to be processed. However, the ratio of the bombardment time to the ion bombardment time is determined by the width of the opening. It is easy to take as large as 5 to 10 times the time. Therefore, for example, when the deposition rate is so high that the ordinary oxidation is not easy, or when it is desired to increase the film density, it becomes easy to receive sufficient plasma and its ion bombardment in an oxygen gas atmosphere.

In the above embodiment, the object to be processed has a complicated rotating body shape, but it may be a flat substrate having a surface to be processed in the circumferential direction of the support 8. In that case, the flat substrate does not rotate, and only one of the vapor deposition correction mask and the discharge shielding plate or the support base needs to rotate, and the surface to be processed receives ion bombardment while moving behind the discharge shielding plate. It will be. Further, in this embodiment, all the rotation axes 10 are kept parallel,
Although the case of revolving around the axis is shown, it may be a non-parallel axis having an inclination according to the shape of the object to be processed. Further, various design changes are possible, such as making the auxiliary electrode a shape other than the coil shape, and maintaining plasma discharge instead of directly connecting to the object holder and applying high frequency power.

[0013]

According to the high-frequency ion bombardment apparatus of the present invention, the above-mentioned configuration can realize the contradictory conditions of a high evaporation rate and a high plasma density, and it is difficult to treat cylindrical, spherical and elliptical bodies. When vacuum deposition is performed on an object to be processed, the ion bombardment effect by plasma can be made uniform and higher efficiency can be obtained, which is an industrially superior effect.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing the structure of an embodiment of a high-frequency ion bombardment device of the present invention.

FIG. 2 is an explanatory view of the principle of the high-frequency ion bombardment device of the present invention.

[Explanation of symbols]

1 vacuum chamber 2 gas introduction adjustment valve 3
High frequency power supply 4 Matching circuit 5 Auxiliary electrode 6
Evaporation source 7 Insulator 8 Support 9
Object to be processed 10 Holder 11 Rotation axis 12 Discharge shielding plate and evaporation correction mask 1
3 Quartz film pressure gauge 21 Vacuum chamber 22 Adjustment valve 2
3 High frequency power supply 24 Matching circuit 25 Coiled auxiliary electrode 2
6 Evaporation source 29 Object to be processed 30 Rotating axis 3
2 Discharge shield plate 34 Evaporation chamber 35 Ion impact chamber 3
6 Opening width adjusting member 37 Shield plate opening 38 Exhaust port

Claims (6)

[Claims] A vacuum chamber is substantially divided into an evaporation chamber and an ion bombardment chamber. An evaporation source is provided in the evaporation chamber, an object to be processed and a support thereof are provided in the ion bombardment chamber, and a high-frequency wave is provided to the support. A high-frequency ion bombardment device comprising an auxiliary electrode for applying electric power, and introducing an atmospheric gas from the ion bombardment chamber into the vacuum chamber. 2. A discharge shielding plate disposed between the evaporation source and the object to be processed substantially divides the inside of the vacuum chamber into an evaporation chamber and an ion bombardment chamber. The high frequency ion bombardment device according to claim 1. 3. The high frequency ion bombardment device according to claim 2, wherein said discharge shielding plate functions as a vapor deposition correction mask. 4. A holding member for rotating a plurality of objects to be processed is held on a revolving support stand in a vacuum chamber, and a discharge shield plate and a vapor deposition correction disposed inside the support stand. 4. The high-frequency ion bombardment device according to claim 1, wherein the inside of the vacuum chamber is substantially separated into an internal evaporation chamber and an external plasma chamber by a mask. 5. The plasma chamber is provided with an atmosphere gas introduction adjustment valve and an auxiliary electrode for applying high-frequency power to a rotating object to be processed.
High frequency ion bombardment equipment 6. The high-frequency ion bombardment device according to claim 4, wherein a discharge shielding plate and a vapor deposition correction mask are fixed to the revolving support base and rotate together with the support base.