TWI426144B - Sputtering apparatus and sputtering film forming method - Google Patents

Description

Sputtering device and sputtering film forming method

The present invention relates to a sputtering apparatus, and more particularly to a sputtering apparatus and a sputtering film forming method capable of suppressing injection of hot electrons generated in sputtering into a workpiece (sputtered product).

Known as a technique for sputtering, there are films such as semiconductors, liquid crystals, plasma displays, and optical disks that require high-quality thin films in workpieces such as metals and plastics.

However, the hot electrons generated in the sputtering cause a temperature rise of the workpiece to be sputtered (Non-Patent Document 1), and in particular, when the workpiece is made of a material having low heat resistance such as plastic, it is in the sputtering. Problems such as workpiece deformation.

In order to suppress the injection of the hot electrons into the workpiece, a device for providing a hot electron attracting member to the groove wall of the vacuum chamber in the electromagnetic field compression type magnetron sputtering apparatus is known (Patent Document 1).

However, since the device is far from the workpiece and the hot electron attracting member, the effect of suppressing the injection of hot electrons into the workpiece is low.

[Non-Patent Document 1] "Thin film production and control technology based on sputtering in the field of optoelectronics", p58, Technical Information Association

[Patent Document 1] Japanese Patent Laid-Open No. Hei 10-96719

Therefore, the object of the present invention is to provide a method of suppressing the injection of hot electrons into a workpiece even when a film having a low heat resistance such as a plastic which is a workpiece is sputtered by sputtering, and the workpiece is not deformed by heat. A sputtering device that waits for the problem.

In order to solve the above problems, the inventors of the present invention have conducted intensive studies and found that the above problems can be solved by providing a member for trapping hot electrons generated during sputtering at a specific position, and the present invention has been completed.

That is, the present invention is a sputtering apparatus which is provided with a target in a vacuum chamber and a rotary table type workpiece holder which is disposed to face the target and has a rotating shaft, and is characterized in that: the rotary type The workpiece holder includes a workpiece holder support portion and a plurality of workpiece holding portions, and the workpiece holding portion is provided on an outer peripheral portion of the workpiece holder support portion, and the rotary type workpiece holder and/or the workpiece holding portion are It is arranged to be rotatable in an axis lying in the same plane perpendicular to the surface of the rotating shaft connecting the target and the rotary workpiece holder, and the thermal electron capture is disposed inside the rotary workpiece holder member.

Furthermore, the present invention is a sputtering film forming method, which is a method for performing film formation on a workpiece mounted on a rotary type workpiece holder that is disposed opposite to a target and is rotated by sputtering a target. , characterized in that the workpiece is rotated by an axis located in the same plane, and the same plane is suspended The surface of the rotating shaft of the above-mentioned target and the rotary-type workpiece holder is directly connected, and the hot electrons are captured by the thermal electron-trapping member provided inside the above-mentioned rotary-type workpiece holder.

According to the present invention, since the hot electrons generated in the sputtering are trapped by the hot electron capturing member, the injection of the hot electrons into the workpiece is suppressed. As a result, even if the material having low heat resistance such as plastic does not excessively increase the temperature of the workpiece, the film formation is performed by sputtering.

Furthermore, the first sputtering apparatus, especially when the workpiece of the three-dimensional shape is subjected to sputtering, in order to improve the throwing power, although magnetically controlled sputtering using an unbalanced magnetic field is used, the system is to improve the electrons in the vicinity of the workpiece. There are many cases where the density is increased for the purpose of increasing the density of the plasma. In this process, as described above, the electron density in the vicinity of the workpiece is increased, whereby the hot electrons easily flow into the workpiece side, and the temperature of the workpiece is further increased. However, according to the present invention, even in the sputtering using the unbalanced magnetic field, the temperature rise of the workpiece can be suppressed.

Further, the present invention has an effect even if it is provided with a mechanism for irradiating radio waves or microwaves with plasma generated by sputtering to increase plasma density (electron density).

Hereinafter, the present invention will be further described, and as one aspect of the present invention, A surface of a cylindrical magnetron sputtering device (hereinafter referred to as a "coaxial magnetron sputtering device") is used for the target.

Fig. 1 is a view schematically showing the main part of a coaxial magnetron sputtering apparatus. In the figure, reference numeral 1 denotes a coaxial magnetron sputtering apparatus, 2 denotes a vacuum chamber, 3 denotes a cylindrical target, 4 denotes a magnet housing portion, 5 denotes a target magnet, and 6 denotes a rotary table type workpiece. In the holder, 7 denotes a workpiece, 8 denotes an exhaust port, 9 denotes a gas introduction port, and 20 denotes a thermoelectron capture member.

Further, Fig. 2 is a cross-sectional view taken along line A-A' of Fig. 1. In the figure, 1 to 9 and 20 denote the same as above, 10 denotes a high voltage power source for plasma, 11 denotes a power source for bias voltage, and 12 denotes ground.

The vacuum chamber 2 is not particularly limited in size and shape if the target 3 and the rotary-type workpiece holder 6 are provided inside. Further, an exhaust port 8 is provided in the vacuum chamber 2. A vacuum pump (not shown) such as a rotary pump or a turbo molecular pump is connected to the exhaust port 8. Further, a gas introduction port 9 for introducing a gas used for the splashing is provided in the vacuum chamber 2. The gas to be used for the splashing is not particularly limited, and examples thereof include argon, nitrogen, oxygen, and the like.

The cylindrical target 3 is a cylindrical pipe having a lower end as a support portion, and the target is attached to a surface other than the support portion by a specific thickness by spraying or the like. Examples of the target include metals such as ruthenium, titanium, zirconium, gold, silver, copper, indium, tin, chromium, aluminum, and carbon, and these oxides or nitrides. Further, examples of the material of the piping include stainless steel, copper, aluminum, and the like. The cylindrical target 3 is configured to be long with the vacuum chamber 2 The side direction (the right angle direction of the paper in Fig. 1) is the same length. The cylindrical target 3 is electrically insulated from the vacuum chamber 2 and is connected to one end of a high voltage power supply. Furthermore, the other end of the high voltage power supply is connected to the vacuum chamber 2 (see Fig. 2).

The magnet housing portion 4 is provided inside the cylindrical target 3, and a target magnet 5 having a length corresponding to the cylindrical target 3 is provided inside. Cooling water for cooling the cylindrical target 3 is supplied between the cylindrical target 3 and the magnet housing portion 4. The target magnet 5 is composed of three magnets 5b, 5c, and 5d that are fixed to the magnet support rod 5a. In the magnets 5b and 5d, the magnet support rod side is set to the N pole, the target side is the S pole, and the magnet 5c is provided with the opposite magnetic pole (see Fig. 3). Further, the magnets 5b and 5d are connected to the lower end of the target magnet 5 to form a circuit (see Fig. 4). In order to generate a balanced magnetic field in the magnet 5, the magnetic force of the magnet 5c is equivalent to the magnetic force of the magnet composed of the magnets 5b and 5d. To generate an unbalanced magnetic field, the magnetic ratio of the magnet 5c is used. The magnet of the magnets 5c and 5d may have a weak magnetic force.

The turntable workpiece holder 6 is configured to face the target. As shown in Fig. 5, the turntable type workpiece holder 6 has a substantially cylindrical shape with the workpiece holder support portion 6a and a plurality of workpiece holding portions 6b, and the workpiece holding portion 6b is provided with a plurality of hooks for fixing the workpiece. Part 6c. The workpiece holding portion 6b is provided on the outer peripheral portion of the workpiece holder support portion 6a. The turntable workpiece holder 6 and/or the workpiece holding portion 6b are arranged to be rotatable in parallel axes located in the same plane, which is perpendicular to the coupled cylindrical target The axis of the material 3 and the surface of the rotating shaft of the rotary table type workpiece holder 6 are preferably arranged to be rotatable by a cylindrical target 3 parallel to the axis, and each independently or synchronously rotates (revolution, rotation) ). The turntable workpiece holder 6 is electrically insulated from the vacuum chamber 2.

Inside the rotary-type workpiece holder 6, a thermal electron-trapping member 20 for capturing hot electrons generated in sputtering is provided. The hot electron capturing member 20 is formed to have the same length as the workpiece holding portion 6b of the rotary type workpiece holder 6, and is composed of a cylindrical hot electron capturing portion 20a and its supporting portion 20b as shown in Fig. 6. . The thermo-electron trap portion 20a and the support portion 20b are preferably made of a material that can replenish hot electrons, such as a metal such as copper or aluminum, or an alloy such as stainless steel. Further, in particular, the hot electron trapping portion 20a is preferably made of a material having a hole through which a gas or a sputtering method is passed, and for example, a gold mesh, a mesh, a punched metal plate, or the like is preferable. Further, it is preferable that the hot electron capturing member 20 is biased, in which case the hot electron capturing member 20 is insulated from the vacuum chamber 2 and the rotary disk holder 6, and this is connected to one end of the bias power source 11, and It is preferable to set the other end of the bias power source 11 to be grounded. When the bias voltage is applied to the hot electron capturing member 20, it is preferably 0 to +200 V. However, when the voltage of the bias voltage is too high, damage is caused to the film formation, so that it is preferably about +50 V.

Further, as another aspect of the turntable type workpiece holder used in the present invention, as shown in Fig. 7, it is exemplified that a small turntable type workpiece holding is mounted on the turntable type workpiece holder support portion 6a. With 15 people. The small-sized rotary-type workpiece holder 15 is the same as the rotary-type workpiece holder 6 and is composed of a workpiece holder support portion and a workpiece holding portion, and the workpiece holding portion has a plurality of Number hooks. The small turntable workpiece holder 15 and its workpiece holder support portion are arranged to be rotatable in parallel axes located in the same plane, which is perpendicular to the axis of the cylindrical target 3 and the rotary disc type The surface of the rotating shaft of the workpiece holder 6 is preferably provided so as to be rotatable by a cylindrical target 3 parallel to the axis, and independently or synchronously rotated (revolved, rotated). At this time, the hot electron capture member 20 is disposed inside the turntable type workpiece holder 6 and/or the small turn type workpiece holder 15.

In the above-described apparatus, in order to perform sputtering, first, after the vacuum chamber 2 is exhausted, a sputtering gas is supplied. Next, power is supplied from the high-voltage power source 10 connected to the target 3 and the vacuum chamber 2 (when the DC power source is used, the target 3 is set as the cathode), and glow discharge is started, and sputtering can be started.

In the above apparatus, although hot electrons are generated simultaneously with the start of sputtering, the hot electrons are absorbed by the hot electron trapping member 20 provided inside the turntable type workpiece holder 6, and reach the ground. As a result, the injection of hot electrons into the workpiece is suppressed. Furthermore, by applying a positive bias to the hot electron capture member 20, the capture rate of hot electrons can be increased.

According to the coaxial magnetron sputtering apparatus of the present invention described above, the workpiece is formed under the following conditions, and since the injection of the hot electrons into the workpiece is suppressed, the workpiece after the film formation is free from deformation or the like.

"film formation conditions"

Workpiece: ABS resin

Sputtering gas: argon

Target: Titanium

Magnetic field: unbalanced

In-chamber vacuum: 10 ^-3 ~10 ^-4 Torr

Input power: 10kW

Power mode: DC

Recovering the components of hot electrons: copper mesh

Bias applied to components that replenish hot electrons: +50V

Time; 20~30 minutes

Further, in the above description, although a coaxial type magnetron sputtering apparatus using a cylindrical target as a target is described, the present invention provides hot electron capture on the inside of the rotary type workpiece holder. The member is characterized in that it does not affect the type of the target, and the like, for example, can be carried out even for a magnetron sputtering device using a flat-plate target as a target, a sputtering device not using a target magnet, and the like.

[Industry use feasibility]

Since the present invention can effectively suppress the hot electrons generated by sputtering, it can be applied to sputtering of materials having low heat resistance such as plastics. Therefore, it can be effectively utilized in the case of forming a thin film of a semiconductor, a liquid crystal, a plasma display, an optical disk, or the like which requires a high-quality film on a workpiece such as a metal or a plastic.

1‧‧‧ coaxial magnetron sputtering device

2‧‧‧vacuum chamber

3‧‧‧ Target

4‧‧‧Magnet storage unit

5‧‧‧Target magnet

5a‧‧‧Magnetic support rod

5b‧‧‧ magnet

5c‧‧‧ magnet

5b‧‧‧ magnet

6‧‧‧Rotary workpiece holder

6a‧‧‧Workpiece holder support

6b‧‧‧Working Holder

6c‧‧‧ hook

7‧‧‧Workpiece

8‧‧‧Exhaust port

9‧‧‧ gas inlet

10‧‧‧High voltage power supply for plasma

11‧‧‧Power supply for bias

12‧‧‧ Grounding

15‧‧‧Small turntable workpiece holder

20‧‧‧ Components for replenishing hot electrons

20a‧‧‧Thermal Electronic Capture Department

20b‧‧‧Support Department

Fig. 1 is a view showing a main part of a coaxial magnetron sputtering apparatus of the present invention.

Fig. 2 is a cross-sectional view taken along line A-A' of Fig. 1.

Fig. 3 is a view showing the structure of a magnet.

Fig. 4 is a view showing the structure of a magnet viewed from the B direction of Fig. 2;

Fig. 5 is a view showing the construction of a rotary type workpiece holder.

Fig. 6 is a view showing the configuration of a member for capturing hot electrons.

Fig. 7 is a view showing another configuration of a rotary type workpiece holder.

1‧‧‧ coaxial magnetron sputtering device

2‧‧‧vacuum chamber

3‧‧‧ Target

4‧‧‧Magnet storage unit

5‧‧‧Target magnet

6‧‧‧Rotary workpiece holder

7‧‧‧Workpiece

8‧‧‧Exhaust port

9‧‧‧ gas inlet

20‧‧‧ Components for replenishing hot electrons

Claims (8)

A sputtering device is provided with a target and a rotary table type workpiece holder disposed opposite to the target and having a rotating shaft in the vacuum chamber, wherein the rotary type workpiece holder has a workpiece holder support And a plurality of workpiece holding portions, wherein the workpiece holding portion is provided at an outer peripheral portion of the workpiece holder support portion, and the rotary type workpiece holder and/or the workpiece holding portion are disposed to be in the same plane The shaft rotates perpendicular to a surface of the rotating shaft connecting the target and the rotary workpiece holder, and a thermal electron capturing member is disposed inside the rotary workpiece holder. The sputtering apparatus according to claim 1, wherein the thermoelectron capturing member can apply a bias voltage. The sputtering apparatus according to claim 1, wherein the thermoelectron capturing member has a hole through which gas or sputtering particles pass. The sputtering apparatus according to the first aspect of the invention, further comprising a magnet for a target. The sputtering apparatus according to claim 1, wherein the target magnet generates an unbalanced magnetic field. The sputtering apparatus according to claim 4, wherein the target is a cylindrical type, and the target magnet is provided inside the target. A method for sputter deposition, which performs sputtering on a workpiece mounted on a rotary-type workpiece holder that is disposed opposite to a target and is rotated by sputtering a target, and is characterized in that: Rotating the workpiece in an axis in the same plane perpendicular to a surface of the rotating shaft connecting the target and the rotary workpiece holder, and disposed on the inner side of the rotary workpiece holder The hot electron capture member captures hot electrons. The sputtering film forming method according to claim 7, wherein the sputtering of the target is performed by magnetron sputtering.