JPH07157877A - Sputtering device - Google Patents

Abstract

PURPOSE:To provide a sputtering device capable of forming a thin film on a substrate in a uniform thickness. CONSTITUTION:This sputtering device is provided with an ion source 2 for injecting an ion beam A into a vacuum chamber 1, a target 3 irradiated with the ion beam and emitting a film forming particle B and a substrate 4 receiving the particle B to form a thin film on it. The target 3 is turned by a servomotor 8C, the servomotor 8C is driven by a random position signal to change the flying direction of the particle B randomly, and the thickness of the thin film is uniformized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sputtering apparatus used for depositing a dielectric optical multilayer film on a substrate or the like.

[0002]

2. Description of the Related Art FIG. 4 shows a schematic plan structure of a conventional sputtering apparatus. In the figure, 1 is a vacuum chamber, 2 is an ion source for irradiating the interior of the vacuum chamber 1 with ions, and 3 is an ion source 2 for irradiating an ion beam A such as argon ions to form film forming material particles B. Indicates a target that emits. The film-forming material particles B emitted from the target 3 are emitted with a main axis in the normal direction corresponding to a half angle between the incident angle θ ₁ and the reflection angle θ ₂ of the ion beam A. It is attached to the surface of the substrate 4 supported by 5. The substrate holder 5 is rotated by the rotation driving means 6 at a speed of about 6 to 12 rotations per minute while keeping the plate surfaces parallel.

Generally, a thin film is formed on the substrate 4 by the sputtering apparatus having the structure shown in FIG. 4. However, when the area of the substrate 4 becomes large, there is a drawback that the film thickness of the thin film 4A has a distribution as shown in FIG. is there. As one method of solving this drawback, as shown in FIG. 6, the area of the ion emission surface of the ion generation source 2 is increased so that the target 3 is irradiated with the ion beam A over a wide range, or As shown in FIG. 7, a structure is provided in which a rotation driving means 6 for rotating the substrate holder 5 and a linear driving means 7 for moving the rotation center position are provided, and the rotation center position is moved along the straight line by the linear driving means 7. Can be considered.

[0004]

When the structure shown in FIG. 6 is adopted, there is a disadvantage that the ion generating source 2 becomes large and expensive. Further, in the case of adopting the structure shown in FIG. 7, since the rotation driving means 6 and the linear driving means 7 have to be provided, the structure becomes complicated, and there is a drawback that the cost is increased in this respect. Further, it was found that the film thickness cannot be made uniform even by controlling the linear driving means 7 only by moving the rotation center position of the substrate 4 in a constant cycle.

[0005]

In the present invention, a random driving means for randomly changing the direction of the target is provided in the sputtering apparatus, and the deposition position of the film-forming material particles is randomly changed for a substrate having a larger area. Is also configured to make the film thickness of the formed thin film uniform.

According to the structure of the present invention, since only the random driving means for randomly changing the direction of the target is provided, the cost is slightly increased, and a thin film having a uniform film thickness on a large-area substrate. It is possible to inexpensively make a sputtering apparatus capable of forming a film.

[0007]

1 and 2 show a structure of a sputtering apparatus according to the present invention. FIG. 1 is a plan view of the sputtering apparatus viewed from above, and FIG. 2 is a side view. In the figure, 1 is a vacuum chamber,
2 is an ion generation source, 3 is a target, 4 is a substrate on which a thin film is to be deposited, 5 is a substrate holder, and 6 is a rotary drive device, which is the same as in the conventional art.

The present invention is characterized by a structure provided with a random driving means 8 for randomly changing the direction of the target 3 (direction of the normal line X toward the substrate 4). The random driving means 8 includes a random position signal generator 8A, a servo motor controller 8B, a servo motor 8C, and a position detector 8D such as a potentiometer for detecting the direction of the target 3 driven by the servo motor 8C. , And an analog adder 8E provided on the input side of the servo motor controller 8B.

The random position signal generator 8A is composed of a voltage generator whose voltage changes randomly. The random voltage signal output from the random position signal generator 8A is input to the analog adder 8E and added to the voltage generated by the position detector 8D, so that the addition result always converges to zero. Is driven. Target 3
Of the ion beam A irradiated on the target 3
At the irradiation point (preferably this irradiation point is on the axis of the rotation axis of the target 3) is within the range from the end of the substrate 4 to the end thereof. The rotation speed of the rotation drive means 6 is about 6 to 12 rotations per minute. An example of the voltage generated by the random position signal generator 8A is shown in FIG. By giving this voltage signal to the analog adder 8E, when a value is generated in the addition result of the analog adder 8E, the servo motor 8C is driven in the direction in which the value becomes zero, and the addition result of the analog adder 8E becomes zero. Then, the servo motor 8C stops rotating. In this state, the target 3 stops at the new rotation angle position. Therefore, the random position signal generator 8A
As shown in FIG. 3, the voltage value output from the target 3 randomly changes the direction of the target 3 relative to the substrate 4, and the deposition position of the film-forming material particles B can be changed randomly. .

[0010]

As described above, according to the present invention, by changing the direction of the target 3 at random with respect to the substrate 4, the flight direction of the film-forming material particles B flying from the target 3 toward the substrate 4 is changed. It changes at random, whereby the attachment position on the substrate 4 changes at random.

As a result, it is possible to prevent the film thickness distribution as shown in FIG. 5 from being concentrated in the center. In particular, even if the area of the substrate 4 is large, it is possible to form a thin film having a uniform thickness.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

FIG. 2 is a side view of FIG.

FIG. 3 is a waveform diagram for explaining the operation of the present invention.

FIG. 4 is a plan view for explaining a conventional technique.

FIG. 5 is a cross-sectional view for explaining a defect of the conventional technique.

FIG. 6 is a plan view showing a conventional example for solving the drawback described in FIG.

FIG. 7 is a plan view similar to FIG.

[Explanation of symbols]

 1 Vacuum Chamber 2 Ion Source 3 Target 4 Substrate 5 Substrate Holder 6 Rotation Driving Means 8 Random Driving Means 8A Random Position Signal Generator 8B Servo Motor Controller 8C Servo Motor 8D Position Detector 8E Analog Adder

Claims (1)

[Claims] 1. A. An ion generation source that irradiates an ion beam into the vacuum chamber, a target that is irradiated by the ion beam emitted from this ion source and emits film-forming material particles, and the film-forming material particles emitted from this target on the surface A sputtering apparatus configured to include a substrate holder supporting a substrate to be attached, B. Rotation driving means for rotating the substrate holder, C.I. Random driving means for randomly changing the radiation direction of the film-forming material particles of the target with respect to the surface of the substrate, the sputtering apparatus.