JPH1192924A - Sputtering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the content volume of a vacuum tank while plural target blocks are housed in the vacuum tank and to simplify a feeder circuit for discharge and piping for cooling. SOLUTION: A target house 15 is connectedly provided with a flat box type vacuum tank 2 in the lower direction of the vacuum tank 2. In the target house 15, four target blocks 22a, 22b, 22c and 22d are arranged so as to be switched to turret systems. By the rotation of a turret board, one target block 22a can be moved to the using position confronting with the ratary face of a substrate holder 5. Only to the target block 22a moved to the using position, the feed of power for discharge and the feed of cooling water are executed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sputtering apparatus containing a plurality of target blocks.

[0002]

2. Description of the Related Art Sputtering is performed when forming various thin films such as an optical thin film and a conductive thin film. In sputtering, cations generated by glow discharge are electrically accelerated so as to collide with a target material, and atoms struck out thereby are deposited on a base substrate, thereby forming a film. An inert gas such as an argon gas is introduced into the vacuum chamber for glow discharge, but a reactive gas such as an oxygen gas or a nitrogen gas is also introduced when performing the chemically reactive sputtering.

[0003] A thin film formed by sputtering has a disadvantage that it takes more time to form a film than a thin film formed by a vacuum deposition method represented by a resistance heating method or an electron beam heating method, but the film structure is dense. Thus, there is an advantage that a physically and chemically stable product can be obtained, and a thin film having a strong adhesive force to a substrate can be obtained.

[0004] The sputtering apparatus is constituted by accommodating a substrate holder holding a base substrate in a vacuum chamber and a target block, and further comprises a vacuum exhaust device for evacuating the vacuum chamber, a substrate holder, An electrical system for generating glow discharge between the target block and a device for supplying an inert gas or a reactive gas is provided.

The target block is formed by fixing a target material to a target holder serving as a negative electrode during film formation, and is disposed inside a vacuum chamber so as to face the underlying substrate. If the temperature of the target block becomes high due to glow discharge during film formation, the electric resistance of the target holder increases, suppressing the discharge current and making it difficult to keep the glow discharge stable. It is customary to provide piping for use.

On the other hand, a sputtering apparatus suitable for mass production of a thin film has a plurality of target blocks arranged inside a vacuum chamber as described in, for example, Japanese Patent Application Laid-Open No. 7-70748. By mounting the same target material on each of the target blocks, and simultaneously performing film formation while rotating the substrate holder, the film formation time can be reduced. It is also possible to use a plurality of target blocks with different types of target materials mounted thereon, and this makes it possible to form a multilayer film combining different types of thin films by a single evacuation.

[0007]

As described above, when a plurality of target blocks are arranged in a vacuum chamber, a single-layer film,
Efficient film formation can be achieved with any of the multi-layer films, but it is inevitable that the internal volume of the vacuum chamber will increase to secure the installation space for the target block, and the time required for one evacuation Becomes longer. In addition, a water cooling pipe is required for each target block, and a shutter mechanism for controlling the start and stop of film formation must be provided for each target block. Easy to convert.

The present invention has been made in view of the above background, and an object of the present invention is to arrange a plurality of target blocks in a vacuum chamber without increasing the internal volume of the vacuum chamber so much, and to sequentially arrange these target blocks. By using
It is an object of the present invention to provide a sputtering apparatus capable of forming a film with a sufficient film thickness after one evacuation or forming a multilayer film.

[0009]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention has a plurality of target blocks which can be switched and used in a turret type. A plurality of target blocks are held on a rotatable turret plate. By switching and rotating the turret plate, one of the plurality of target blocks can be moved to a position facing the rotation surface of the substrate holder.

The target block is composed of a cylindrical target holder and a cylindrical target material fixed to an outer peripheral surface of the target block. Both ends of the target block are held between a pair of turret plates, and the turret plate is rotated. By switching the target block, the turret structure does not need to be complicated. Furthermore, by supplying power for discharging and supplying cooling water only to the target block that has been moved to the use position, power supply wiring and cooling water piping are simplified, The miniaturization and low cost of the device are achieved.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1 and 2 show the appearance and a cross section of a main part of a sputtering apparatus to which the present invention is applied. An openable and closable door 3 is provided on the rear side of the flat box-shaped vacuum chamber 2. By opening the door 3, the substrate holder 5 can be taken in and out of the vacuum chamber 2. Substrate holder 5
Is formed in a conical dome shape, and its peripheral surface is formed with an opening corresponding to the outer diameter of the underlying substrate. As shown in FIG. The substrate 6 can be placed. The base substrate 6 is a target for forming a thin film by sputtering.
Glass lens, plastic lens, glass plate,
Various objects such as plastic plates can be targeted.

A gear 7 is fixed to the top of the substrate holder 5. As shown in FIG. 2, the gear 7 has a larger diameter than the top of the substrate holder 5 and can be supported by a guide rail 8 fixed to a top plate of the vacuum chamber 2. Therefore, the substrate holder 5 can be accommodated in the vacuum chamber 2 while sliding the lower surface of the gear 7 on the guide rail 8. Then, when the substrate holder 5 is sent to a predetermined position, the drive gear 10 provided on the top plate of the vacuum chamber 2 meshes with the gear 7 of the substrate holder 5.

In a predetermined storage position, the lower surface of the gear 7 is rotatably held by rotation supporting means such as rollers and bearings. Therefore, when the drive gear 10 is rotated by the motor 11, the substrate holder 5 Rotate in horizontal position. The vacuum chamber 2 is provided with an appropriate vacuum exhaust device 12 such as an oil diffusion pump, a molecular turbo pump, or a scroll-type dry vacuum pump. The inside can be made a high vacuum of 10 ^-6 Torr or less. A target house 15 is provided between the pair of legs 14 supporting the vacuum chamber 2. As shown in FIG. 2, the target house 15 is spatially connected to the vacuum chamber 2, and is evacuated by the vacuum exhaust device 12 in the same manner as the vacuum chamber 2.

As schematically shown in FIG. 3, a pair of turret plates 16 and 17 are provided inside the target house 15, and one of the turret plates 16 is integrally connected to a rotating shaft 19 by bolts 18. The other turret plate 17
Is rotatably fitted to the fixed support shaft 20. Between the turret plates 16 and 17, there are four target blocks 22a, 22b, 22c and 2 each having a cylindrical shape.
2d is fixed, and four partition plates 23 are fixed so as to partition between the respective target blocks (in FIG. 3, the partition plates 23 are not shown).

A gear 24 is fixed to the rotating shaft 19 and can be rotated by driving a motor 25 fixed outside the target house 15. The turret plate 16 rotates with the rotation of the rotation shaft 19, and the other turret plate 17 connected by the target block and the partition plate 23 also rotates around the support shaft 20 in the same direction. In addition,
Reference numeral 21 denotes a rotary shutter.

Both ends of the target block protrude from the outer surfaces of the turret plates 16 and 17 and solenoids 26 and 27
When the electrodes 26a and 27a come into contact with each other, power is supplied. Solenoids 26 and 27 and electrode 2
Reference numerals 6a and 27a denote target blocks which have been moved to a portion communicating with the vacuum chamber 2, that is, a use position facing the rotating surface of the substrate holder 5 among the four target blocks held by the turret plates 16 and 17 (FIG. 3 are provided only at positions facing both ends of the target block 22a).

Water is supplied only for cooling the target block 22a to the target block 22a that has moved to the use position. This is because, as indicated by the broken line in FIG. 3, the cooling water from the water supply pipe inserted inside the rotating shaft 19 is supplied only to the target block 22a through the water supply passage formed inside the turret plate 16. Achieved by: After passing through the target block 22a, the cooling water is drained through a water supply passage of the other turret plate 17 through a drain pipe provided inside the spindle 20.

FIG. 4 shows a cross section of a main part of the turret plate 16 side. The rotating shaft 19 is hermetically and rotatably supported on an outer peripheral surface of a water supply pipe 30 fixed to an outer wall of the target house 15, and the rotating shaft 19 is rotatable around the water supply pipe 30. Of course, the space between the outer peripheral surface of the rotating shaft 19 and the outer wall of the target house 15 is also hermetically sealed. A plug 31 for fitting the cooling water that has passed through the inside of the water supply pipe 30 only upward is fitted into the tip of the water supply pipe 30.

The turret plate 16 is fixed to the rotating shaft 19 with bolts 18. Inside the turret plate 16, four water supply channels 33 are provided radially for each of the mounting positions of the target blocks 22a to 22d. However, as described above, the stopper 31 sends water only upward,
In FIG. 4, water is supplied only to the target block 22a.

A spindle 20 is provided on the inner surface of the turret plate 16.
Is fixed. In this embodiment, since the support shaft 20 is fixedly used, when the turret plate 16 rotates, the tip of the support shaft 20 also acts as a bearing. The support shaft 20 can be used in a rotary manner by making the support shaft 20 engage with the turret plate 16 in the rotation direction. In this case, the other end of the support shaft 20 is connected to the other turret. What is necessary is just to engage with the board 17 in the rotation direction.

The target block 22a comprises a target material 36, a target holder 37, and a magnet block 38. The target material 36 is obtained by forming a thin film material to be deposited on the base substrate 6 into a cylindrical shape, and is fixed to the outer peripheral surface of a cylindrical target holder 37 made of a good conductor such as copper. The magnet block 38 includes a permanent magnet 3 on a substrate 38a made of soft iron.
8b and 38c are fixed, and the target holder 37
In the hollow part of

The permanent magnet 38b has a longitudinal direction coinciding with the target holder 37, and the magnetic pole at the tip facing the inner wall of the target holder 37 is an N pole. The permanent magnet 38c is
The permanent magnet 38b is disposed so as to surround the permanent magnet 38b in a rectangular shape, and the magnetic pole at the tip facing the inner wall of the target holder 37 is an S pole. As a result, magnetic lines of force are generated in a direction perpendicular to the generatrix on the outer surface of the target material 36, and the sputtering efficiency can be improved.

Electrode members 40 are fixed to both ends of the target holder 37 by fitting, and the tips protrude outward from the turret plate 16. This electrode member 40
It is electrically insulated from the turret plate 16 by Teflon or the like. When the solenoid 26 fixed to the outer wall of the target house 15 is driven, the electrode 26a projects and comes into contact with the electrode member 40. This structure is the same on the other side of the target block 22a. Thus, by setting both ends to the same potential, stable sputtering can be performed.

When the electrode 26a comes into contact with the electrode member 40 of the target holder 37, the target block 37 becomes electrically active and serves as a negative electrode for discharging. As is well known, the substrate holder 5 functions as an anode during discharge.
Since a water supply hole for passing cooling water is formed in the electrode member 40, the cooling water sent from the water supply pipe 30 flows through a path shown by a broken line in the figure, and flows through the target block 22a during sputtering. cool. Also on the other turret plate 17 side, the cooling water that has passed through the target holder 37 passes through a drain passage formed inside the turret plate 17, and is further drained through a drain pipe provided inside the spindle 20. You.

When performing sputtering, first, the vacuum chamber 2 and the target house 15 are
High vacuum inside. Next, an inert gas such as an argon gas is introduced until an appropriate degree of vacuum is obtained. The motor 25 is moved so that the target material 22a to be used first comes to the use position.
To rotate the turret plates 16 and 17.

Cooling water is supplied from the water supply pipe 30 to cool the target block 22a. Next, solenoid 2
6 and 27 are driven to bring the respective electrodes 26a and 27a into contact with both ends of the target block 22a. With the shutter 21 closed, the target block 22a is
A high voltage is applied so that the substrate holder 5 becomes a positive electrode.
Thus, glow discharge is started, but sputtering is not yet performed because the shutter 21 is closed.

When the shutter 21 is opened, the sputtering is started, and the atoms scattered from the target material 36 are deposited on the base substrate 6. At this time, the substrate holder 5 is slowly rotating. Therefore,
The atoms scattered from the target material 36 adhere to all of the underlying substrates 6 held by the substrate holder 5. The deposited film thickness can be monitored by a film thickness monitoring device 44 attached to the top plate of the vacuum chamber 2 located almost directly above the target house 15.

When it is confirmed by the film thickness monitoring device 44 that a thin film having a predetermined film thickness is formed on the base substrate 6 by sputtering using the target block 22a, the shutter 21 is closed. Next, solenoids 26 and 27
Is turned off, and the electrodes 26a and 27a are separated from both ends of the target block 22a. This stops the discharge,
Further, by temporarily stopping the supply of the cooling water, the sputtering by the target block 22a ends.

Subsequently, in order to perform sputtering in the target block 22b, the turret plates 16 and 17 are rotated by 90 ° by driving the motor 25. The stopper 31 fixed to the tip of the water supply pipe 30 allows the target block 2
A water supply channel for 2b is formed. An electromagnetic valve may be provided in front of the water supply pipe 30 so that the water supply is automatically cut off while the turret plates 16 and 17 are rotating, and the opening and closing of the electromagnetic valve may be automatically controlled.

After the target block 22b is moved to the use position, sputtering is performed by supplying cooling water, driving the solenoids 26 and 27, and opening the shutter 21 in the same manner as in the sputtering process using the target block 22a. Can be. Thereafter, sputtering can be continuously performed using the target blocks 22c and 22d in the same procedure.

When the same target material is used for the target blocks 22a to 22d, four times of sputtering can be performed while changing the target material anew, so that a sufficient vacuum can be formed by one evacuation. Becomes possible. If the type of the target material is changed for each target block, a multilayer film can be formed by sputtering with a single evacuation.

When the target material is exchanged, the turret plates 16 and 1 are removed together with the target block by pulling out the support shaft 20 and removing the bolt 18.
7 is taken out of the target house 15. Thereafter, the target block can be freely exchanged outside the target house 15 by removing a bolt fixing the electrode member 40 to the turret plate 16 or the like.

FIG. 5 schematically shows another embodiment of the present invention. In this embodiment, a cylindrical substrate holder 51 is accommodated in a rectangular tube-shaped vacuum chamber 50, and an underlying substrate is held on the outer peripheral surface of the substrate holder 51. A target house 52 is connected to one side wall of the vacuum chamber 50, and a target mechanism portion 53 including the turret plates 16 and 17 used in the above-described embodiment is rotatably arranged around a vertical axis. Also in this embodiment, the same effect can be obtained by switching the target blocks by rotating the turret plates 16 and 17 by 90 °.

[0034]

As described above, according to the sputtering apparatus of the present invention, the turret plate holding a plurality of target blocks is rotated so that the target blocks can be switched and used. The target mechanism part including the turret plate can be collectively collected at a location, and the inner volume of the vacuum chamber can be increased compared to the case where multiple target blocks are arranged at various locations in the vacuum chamber. In addition, the power supply circuit for discharge and the piping equipment for cooling are simplified, which greatly contributes to the reduction in size and cost of the sputtering apparatus.

[Brief description of the drawings]

FIG. 1 is an external view of a sputtering apparatus using the present invention.

FIG. 2 is a schematic sectional view of a principal part of the sputtering apparatus shown in FIG.

FIG. 3 is a schematic sectional view of a target house part of the sputtering apparatus shown in FIG.

FIG. 4 is a sectional view of a main part of a turret mechanism.

FIG. 5 is a schematic view showing another embodiment of the present invention.

[Explanation of symbols]

 2 Vacuum tank 5 Substrate holder 6 Base substrate 15 Target house 16, 17 Turret plate 19 Rotating shaft 20 Support shaft 22a Target block 26, 27 Solenoid 26a, 27a Electrode 36 Target material 37 Target holder 38 Magnet block 40 Electrode member

Claims (4)

[Claims] 1. A substrate holder rotatably accommodated in a vacuum chamber and holding an underlying substrate on which a thin film is to be deposited, and a substrate holder arranged to face a rotating surface of the substrate holder and facing the underlying substrate by discharge. A target block that scatters a thin film material by holding a plurality of target blocks on a rotatable turret plate, and switching and rotating the turret plate to convert one of the plurality of target blocks to a substrate. A sputtering apparatus characterized in that it can be moved to a position facing a rotating surface of a holder. 2. The method according to claim 1, wherein the target block comprises a cylindrical target holder and a cylindrical target material fixed to an outer peripheral surface of the target block, and both ends of the target block are held between a pair of turret plates. The sputtering device according to claim 1. 3. The discharge power is supplied from both ends of only the target block moved to a position facing the rotation surface of the substrate holder.
The sputtering apparatus as described in the above. 4. The sputtering apparatus according to claim 1, wherein cooling water is supplied only to the target block moved to a position facing the rotation surface of the substrate holder.