JPH06299322A - Sputtering device - Google Patents

Abstract

PURPOSE:To provide a sputtering device where the temperature rise in a mask is restrained and accordingly the fusion of a substrate to the mask and the thermal deformation of it are prevented. CONSTITUTION:A mask reflector 20 made of a copper alloy is arranged above a mask 20. The mask reflector 20 consists of a ring part 21, a center part 22 and ribs 23 for joining the ring part 21 and the center part 22. The ring part 21 of the mask reflector 20 has the form of a flat ring and is abutted on the upper surface of an outer mask part 19 of the mask 12 and a device body 11 each. The center part 22 of the mask reflector 20 has the form of a cylinder which covers the upper end part of an inner mask part 15 of the mask 12 leaving a space. The ribs 23 of the mask reflector 20 have a rectangular cross section wider than that of ribs 16 of the mask 12 to be located just above the ribs 16 of the mask 12 leaving a space at the time of fitting.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sputtering apparatus, and more particularly to a sputtering apparatus capable of preventing deformation of a substrate and welding to a mask by suppressing a temperature rise of the mask.

[0002]

2. Description of the Related Art In a magnetron sputtering device,
Plasma discharge is performed in a space where the electric field and magnetic field are orthogonal to each other, and inert gas ions such as argon ions are made to collide with a target that is a cathode, and sputtered particles are deposited on the substrate facing each other. The film forming process is performed by utilizing the phenomenon.

FIG. 5 shows a main part of a planar magnetron sputtering apparatus. In the figure, a disk-shaped target 2 made of aluminum or gold is fixed to a lower portion of a backing plate 1 which is a cathode. A ring-shaped anode 3, which is an anode, is arranged around it. A disk-shaped magnet 5 is arranged above the backing plate 1. The magnet 5 is rotatably held by a drive shaft 4 which is concentric with the target 2, and the drive shaft 4 is rotationally driven by a motor 8 via gears 6 and 7. In the figure, 9 is a cylindrical protective cover for protecting the magnet 5. The axis C of the drive shaft 4 and the center O of the magnet 5 are offset, and when the drive shaft 4 rotates, the magnet 5 eccentrically rotates. As a result, the circular magnetic field is eccentrically rotated with respect to the target 2, and the target 2 is uniformly sputtered by the plasma discharge (indicated by P in FIG. 5) along the magnetic field.

A disk-shaped substrate 10 such as an optical disk is arranged below the target 2 so as to face it. The substrate 10 is in contact with the lower surface of the mask 12 fitted in the apparatus body 11, and is pressed toward the mask 12 by a pusher (not shown). The mask 12 is made of a copper alloy having a high thermal conductivity, and as shown in FIG. 6, the flange 1 that masks the outer peripheral portion of the substrate 10.
An outer mask portion 14 having 3 inside the lower end and a poppet-shaped inner mask portion 15 for masking the central portion of the substrate 10 are main constituent members. The inner mask parts 15 are arranged at 90 ° intervals.
It is supported by the outer mask portion 14 via book ribs 16. In the figure, 17 and 18 are cooling water passages formed in the backing plate 1 and the apparatus main body 11, respectively,
Cooling water circulates in the inside. Further, 19 is the apparatus main body 1
It is an adhesion-preventing plate that prevents adhesion of sputtered particles to No.

[0005]

In the above-described sputtering apparatus, sputtered particles emitted from the target 2 collide with and deposit on the substrate 10 to form a thin film. However, since the upper portion of the mask 12 located above the substrate 10 is exposed to the plasma P, not only sputtered particles but also a large amount of electrons in the plasma P collide with each other at a very high frequency. As a result, when sputtering is continuously performed, there is a problem that the temperature of the mask 12 gradually rises by absorbing electrons. Of the parts of the mask 12, the outer mask part 14 fitted to the apparatus body 11 is relatively well cooled by the cooling water circulating in the cooling water passage 18, but the inner mask part 15 is exposed to the plasma P. On the contrary, heat tends to flow from the ribs 16. On the other hand, if the positions of the ribs 16 and the upper end portions of the inner mask portion 15 are lowered and separated from the plasma P, the temperature rise can be reduced, but in this case, the ribs 16 serve as a shield and the film is formed on the substrate 10. There was a problem that could not be performed uniformly.

Then, for example, when the temperature of the inner mask portion 15 reaches about 100 ° C., the substrate 10 made of polycarbonate or the like is used as the inner mask portion 15
Could be welded to the bottom surface of the, or thermally deformed, such as warped. In order to reduce the temperature rise of the mask 12, the voltage applied between the backing plate 1 and the anode 3 may be lowered to reduce the plasma P generated below the target 2, but this method is used. However, there was a problem that the efficiency was significantly reduced and the productivity deteriorated.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to solve the above-mentioned problems of the prior art, to suppress the temperature rise of the mask, and to provide a sputtering apparatus in which the welding of the substrate to the mask and the thermal deformation are prevented. To do.

[0008]

In order to achieve the above object, the sputtering apparatus of the present invention comprises a desired portion of the target side surface of a substrate to be sputter processed, an outer mask portion and an inner mask portion, and In a sputtering device which is covered with a mask composed of ribs to be coupled so as not to partially form a sputtered film on the surface of the substrate, the mask is interposed between the target and the mask. It is characterized in that a mask reflector for shielding the surface on the target side is provided.

[0009]

According to the present invention, the electrons in the plasma collide with the mask reflector and are absorbed. Therefore, almost no electrons collide with the mask, and the temperature rise can be suppressed to an extremely low level.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a planar magnetron sputtering apparatus to which the present invention is applied will be described below with reference to the accompanying drawings. As shown in FIG. 1, also in this embodiment, as in the conventional device, the disk-shaped target 2 is fixed to the lower part of the backing plate 1 which is the cathode,
A ring-shaped anode 3 is arranged around it. A disk-shaped magnet 5 is arranged above the backing plate 1. The magnet 5 is held at a position eccentric to the drive shaft 4, and the drive shaft 4 is rotationally driven by the motor 8 via the gears 6 and 7, whereby the magnet 5 is eccentrically rotated. Also, below the target 2, below the substrate 1
0s are arranged so as to face each other and are pressed against the mask 12 side by a pusher (not shown).

In the sputtering apparatus of this embodiment, a mask reflector 20 made of copper alloy is arranged above the mask 12. As shown in FIG. 2, the mask reflector 2
0 indicates the ring portion 21, the center portion 22, and the ring portion 21.
And a rib 23 that connects the center portion 22 with the center portion 22. The ring portion 21 of the mask reflector 20 has a flat annular shape and abuts on the upper surfaces of the outer mask portion 14 of the mask 12 and the apparatus body 11, respectively, as shown in FIG.

The center portion 22 of the mask reflector 20 is
As shown in FIG. 3 (enlarged sectional view of portion A in FIG. 1), the inner mask portion 15 of the mask 12 has a cylindrical shape that covers the upper end portion with a gap t, and the rib 16 of the mask 12 is provided on the outer peripheral surface thereof. A notch 24 that fits is formed. Further, the rib 23 of the mask reflector 20 has a rectangular cross section wider than the rib 16 of the mask 12, and as shown in FIG.
When the mask 12 is mounted, a gap t is formed just above the rib 16 of the mask 12.
Be positioned with. In the figure, reference numeral 20 is a ring-shaped pressing ring interposed between the anode 3 and the mask reflector 20, and the mask reflector 20 is pressed and brought into close contact with the apparatus main body 1.

The operation of this embodiment will be described below. In the sputtering apparatus of this embodiment, plasma P is generated by applying a voltage between the backing plate 1 and the anode 3.
Occurs, sputtered particles are emitted from the target 2 and collide with and deposit on the substrate 10. At this time, as described above, a large amount of electrons fly in the plasma P, and the electrons are collided with the member exposed to the plasma P. However, in this embodiment, since the inner mask portion 15 and the rib 16 of the mask 12 are covered by the center portion 22 and the rib 23 of the mask reflector 20, most electrons are masked before colliding with the mask 12. I will collide with 20. As a result, the temperature rise of the mask 12 itself was suppressed to an extremely low level, and the substrate 10 in contact with the mask 12 was not welded to the mask 12 or thermally deformed. On the other hand, although the mask reflector 20 becomes high in temperature due to the collision of electrons, the center portion 22 and the ribs 23 thereof are not in contact with the mask 12, so that heat is conducted from the ring portion 21 to the apparatus main body 11 and the inside of the cooling passage 18 is cooled. It is carried outside by cooling water.

In the present embodiment, since the above-mentioned structure is adopted, when sputtering is performed with an output of 10 kw,
It was possible to lower the temperature of the mask 12 by 30 ° C. as compared with the conventional device. Further, when sputtering was performed with an output of 18 kw, the temperature of the mask 12 rose to 133 ° C. in the conventional apparatus, but in the present example, it was 80 ° C.
It became possible to suppress it to about C, and it became possible to secure high productivity.

The aspect of the present invention is not limited to these embodiments, and the material of the mask reflector may be aluminum or steel, for example. Further, the shape of the mask reflector can be variously changed according to the shape of the mask and the like.

[0016]

As is clear from the above description, according to the present invention, the mask reflector interposed between the target and the mask covers the surface of the mask on the target side. It is possible to prevent the substrate from being welded to the mask and thermally deformed. In addition, this makes it possible to increase the applied voltage of sputtering and improve the productivity.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a main part of an embodiment of a planar magnetron sputtering apparatus according to the present invention.

FIG. 2 is a perspective view of a mask reflector.

FIG. 3 is an enlarged view of part A in FIG.

FIG. 4 is a sectional view taken along line BB in FIG.

FIG. 5 is a vertical cross-sectional view showing a main part of a conventional planar magnetron sputtering apparatus.

FIG. 6 is a perspective view of a mask.

[Explanation of symbols]

 1 Backing Plate 2 Target 3 Anode 10 Substrate 12 Mask 14 Outer Mask Part 15 Inner Mask Part 16 Rib 18 Cooling Passage 20 Mask Reflector 21 Ring Part 22 Center Part 23 Rib

Claims (2)

[Claims] 1. A desired portion of a target-side surface of a substrate to be sputter processed is covered with a mask composed of an outer mask portion, an inner mask portion and ribs connecting these portions, and a sputtered film on the surface of the substrate. In a sputtering apparatus in which the formation of a mask is not partially performed, a sputtering apparatus is provided which is interposed between the target and the mask and shields a target side surface of the mask. . 2. The sputtering apparatus according to claim 1, wherein a gap is provided between the mask reflector and the inner mask portion and the rib.