JPH05339726A - Magnetron sputtering device - Google Patents

Abstract

PURPOSE:To improve the efficiency of utilizing a target as well as the- reproducibility of film characteristics, the uniformity of film thickness, step coverage property and film forming speed and to decrease particles. CONSTITUTION:This magnetron sputtering device has a vacuum chamber 8 which can maintain a vacuum state, a vacuum evacuation pump 9 which maintains a reduced pressure atmosphere in this vacuum chamber 8, a gas supply system 10 which supplies a sputtering gas into the vacuum chamber 8 while regulating its flow rate, a cathode 1 which is disposed with a magnet pair 3 and is fixed with the target 5, a substrate 7 which is disposed to face this cathode 1 and is formed with the film by sputtering and a power source 11 which generates plasma between the cathode 1 and the substrate 7 by applying a voltage to the cathode 1. The magnet pair 3 is constituted of a first magnetic pole 3a having a wave from rectangular wave shape and a second magnetic pole 35 having a part enclosing the first magnetic pole 3a and existing between the recessed parts thereof to generate the part where the plasma density is high, i.e., an erosion resin, over the entire surface of the target 5 and to erode the target 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetron sputtering device.

[0002]

2. Description of the Related Art In recent years, a magnetron sputtering apparatus has been widely used for forming a recording film of a magneto-optical disk, an optical disk, a video head.

An example of a conventional magnetron sputtering apparatus will be described below with reference to FIG. In FIG. 4, 21 is a cathode to which a magnet pair 23 that is concentric with the yoke 22 is fixed, 24 is a backing plate that fixes the target 25, and 26 is a cooling water pipe for cooling the magnet pair 23 and the target 25. Reference numeral 27 is a substrate which is arranged so as to face the target 25 and on which a film is deposited by sputtering. Reference numeral 29 is a vacuum exhaust pump for reducing the pressure inside the vacuum chamber 28, and 30 is a gas supply system for supplying a sputtering gas into the vacuum chamber 28. 31 applies a voltage to the cathode 21, and the target 2
5 is a power source for generating plasma on the surface.

The operation of the magnetron sputtering apparatus constructed as above will be described below. First, the inside of the vacuum chamber 28 is evacuated by the vacuum exhaust pump 29 to a degree of vacuum of the order of 10 ⁻⁶ Torr. After that, argon gas is introduced into the vacuum chamber 28 by the gas supply system 30, a vacuum degree of about 5 × 10 ⁻³ Torr is set, and a DC or high-frequency voltage is applied to the cathode 21 by the power supply 31 to make the vacuum chamber 28 A plasma is generated inside. As a result, argon ions are generated. Further, the magnetic field 32 of the magnet pair 23 generates a portion 33 having a high plasma density, and the argon ion target 2
The amount of collision with 5 increases. Then, the particles mainly scatter from the area, that is, the erosion area, and are deposited on the surface of the substrate 27 arranged facing each other to form a film. After that, the erosion area of the target 25 is removed as shown in FIG.

[0005]

However, in the above-described structure, the concentric magnet pair 23 forms a ring-shaped portion having a high magnetic field strength, and the portion of the surface of the target 25 having a high magnetic field strength, that is, the plasma density is high. The amount of collisions of argon ions increases in the high portion, and the scattering of particles increases in the annular erosion region. Therefore, target 2
The erosion of No. 5 is concentrated in the annular erosion region, the amount of the target 25 actually used by sputtering, that is, the utilization efficiency of the target 25 is as low as about 20%, and the replacement frequency of the target 25 becomes high in the case of mass production. Have a problem. Further, since the erosion of the target 25 is fast, there is a problem that the shape change of the target 25 and the change of the magnetic field strength become fast and the reproducibility of the characteristics of the film deteriorates.

Further, since the portion where the plasma density is high is a part of the target 25, the film forming rate is slow, the film quality uniformity and the step coverage are low, and the particles are increased due to the reattachment of the sputtered particles to the target. have.

In view of the above-mentioned conventional problems, the present invention improves target utilization efficiency and film characteristics by generating a portion having a high plasma density, that is, an erosion region, on the entire surface of the target and uniformly eroding the target. An object of the present invention is to provide a magnetron sputtering apparatus capable of improving reproducibility, film thickness uniformity, step coverage, film forming speed, and reducing particles.

[0008]

A magnetron sputtering apparatus according to the present invention comprises a vacuum chamber capable of maintaining a vacuum state, a vacuum exhaust pump for reducing the pressure inside the vacuum chamber, and a flow rate control of a sputtering gas in the vacuum chamber. While supplying a gas supply system, a cathode in which a magnet pair is arranged and a target is fixed, and a substrate which is arranged facing the cathode and is formed by sputtering,
In a magnetron sputtering apparatus equipped with a power source for applying a voltage to a cathode and generating plasma between a substrate, a magnet pair, a first magnetic pole having a waveform or rectangular wave shape, and a first magnetic pole surrounding the first magnetic pole. It is characterized in that it is constituted by a second magnetic pole having a portion located between the concave portions.

[0009]

According to the present invention, since the portion having a high plasma density, that is, the erosion region can be generated on the entire surface of the target by the above-described structure, the target is uniformly eroded, and the target utilization efficiency is improved. Further, since the erosion rate in the target thickness direction is reduced, the magnetic field strength change rate is reduced, and the reproducibility of the film characteristics is improved. Further, since the sputtered particles are scattered from the entire surface of the target, the film thickness uniformity, the step coverage property, and the film formation rate are improved. Furthermore, since reattachment of sputtered particles to the target does not occur, particles can be reduced.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A magnetron sputtering apparatus according to an embodiment of the present invention will be described below with reference to FIGS.

In FIG. 1, 1 is a cathode and 2 is a yoke. As shown in FIG. 2, reference numeral 3 denotes a magnet composed of a first magnetic pole 3a having a corrugated or rectangular wave shape and a second magnetic pole 3b surrounding the first magnetic pole and having a portion located between the recesses. It is a pair. 4 is a backing plate for fixing the target 5, and 6 is a cooling water pipe for cooling the magnet pair 3 and the target 5. A substrate 7 is arranged so as to face the target 5 and a film is deposited by sputtering. Reference numeral 9 is a vacuum exhaust pump for creating a reduced pressure atmosphere in the vacuum chamber 8, and 10 is a gas supply system for supplying the sputtering gas into the vacuum chamber 8 while adjusting the flow rate. 11
Is a power source for applying a voltage to the cathode body 1 to generate plasma on the surface of the target 5.

The operation of the magnetron sputtering apparatus constructed as above will be described below. First, the inside of the vacuum chamber 8 is evacuated by the vacuum exhaust pump 9 to a degree of vacuum of the order of 10 ⁻⁶ Torr. afterwards,
Argon gas is introduced into the vacuum chamber 8 by the gas supply system 10, and the degree of vacuum is set to about 5 × 10 ⁻³ Torr. Here, the target 5 is cooled by the cooling water from the cooling water pipe 6. Next, a direct-current or high-frequency voltage is applied to the cathode 1 by the power source 11 to generate plasma inside the vacuum chamber 8. Argon ions are generated by this plasma and collide with the target 5, so that sputtered particles are scattered from the colliding portion. At this time, the magnetic field 12 of the magnet pair 3 spreads the high plasma density portion 13 over the entire surface of the target 5. Then, the sputtered particles are scattered from the entire surface of the target 5 and are deposited on the surface of the substrate 7 arranged so as to be opposed to form a film. In this way, the entire surface of the target 5 is evenly ground as shown in FIG.

As described above, according to this embodiment, the magnet pair 3 is used.
Since the magnetic field 12 can generate a portion 13 having a high plasma density, that is, an erosion region on the entire surface of the target 5, as shown in FIG. 3, the entire surface of the target 5 is uniformly eroded.

Therefore, the target utilization efficiency can be improved up to 40%.

Further, since the erosion rate in the thickness direction of the target 5 is reduced, the magnetic field strength change rate is reduced, and the reproducibility of the film characteristics can be improved.

Further, since the sputtered particles scatter from the entire surface of the target 5, film thickness uniformity, step coverage,
The film forming speed can be improved.

Furthermore, since reattachment of sputtered particles to the target 5 does not occur, the number of particles can be reduced.

Although the magnet pair 3 is fixed in the above embodiment, it may be rotated, and the target utilization efficiency can be improved up to 60% by rotating it.

[0019]

According to the present invention, as described above, the magnet pair in the cathode is located between the first magnetic pole having the corrugated or rectangular wave shape and the recess surrounding the first magnetic pole. Since the second magnetic pole having the portion is formed, the erosion region can be generated on the entire surface of the target to improve the target utilization efficiency, and the erosion rate in the target thickness direction can be reduced to reduce the magnetic field strength change rate. The reproducibility of the film characteristics can be improved, and since the sputtered particles are scattered from the entire surface of the target, the film thickness uniformity, the step coverage, the film formation speed are improved, and the re-adhesion of the sputtered particles to the target does not occur. It has the effect of reducing particles.

[Brief description of drawings]

FIG. 1 is a sectional view of a magnetron sputtering apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view of a magnet pair in the embodiment.

FIG. 3 is a sectional view showing an eroded state of a target in the example.

FIG. 4 is a sectional view of a conventional magnetron sputtering apparatus.

FIG. 5 is a sectional view showing an eroded state of a target in a conventional example.

[Explanation of symbols]

 1 Cathode 3 Magnet Pair 3a First Magnetic Pole 3b Second Magnetic Pole 5 Target 7 Substrate 8 Vacuum Chamber 9 Vacuum Exhaust Pump 10 Gas Supply System 11 Power Supply

Claims (1)

[Claims] 1. A vacuum chamber capable of maintaining a vacuum state, a vacuum exhaust pump for creating a reduced pressure atmosphere in the vacuum chamber, a gas supply system for supplying a sputtering gas into the vacuum chamber while adjusting the flow rate, and a magnet pair. A cathode arranged and fixed with a target, and a substrate arranged facing the cathode and formed by sputtering,
In a magnetron sputtering apparatus equipped with a power source for applying a voltage to a cathode to generate plasma between a substrate, a magnet pair, a first magnetic pole having a waveform or rectangular wave shape, and a first magnetic pole surrounding the first magnetic pole. A magnetron sputtering apparatus comprising a second magnetic pole having a portion located between the recesses.