JP2685779B2 - Sputtering device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a sputtering device, and particularly to a gas flow adjustment for sputtering that is suitable for performing uniform plasma discharge over a large area.

[Conventional technology]

The sputtering device is used in various product fields as a thin film forming means of various materials. However, since the conventional sputtering device is configured to supply the sputtering gas into the processing space from the periphery of the processing space between the electrodes and exhaust the gas from one side thereof, the film thickness gradually increases in the gas flow direction. Has a tendency to become thin, and when forming a comparatively thick protective film or insulating film of several tens of microns, the film thickness distribution becomes a problem, so it is difficult to form a large area film.

Although it is a plasma CVD apparatus, it is possible to improve the gas flow by symmetrically providing a gas supply port and an exhaust port with respect to the film-forming substrate in order to make the film thickness distribution uniform.
No., published in Japanese Unexamined Patent Publication No. However, it has been found that in the sputtering device, even if the exhaust ports are provided on both sides, the size of the device is increased and the film thickness distribution cannot be sufficiently improved. That is, it was found that the film thickness distribution was bilaterally symmetric but was not entirely uniform.

[Problems to be solved by the invention]

As described above, in the conventional sputtering device, when the electrodes facing each other are enlarged to obtain a large film formation area in order to increase the productivity of the film formation operation, the gas density becomes non-uniform and the film thickness distribution becomes large. However, there was a problem that the variation of was beyond the allowable range. When the gas density is made uniform, the size of the apparatus is increased, but the film thickness distribution is not improved.

Therefore, an object of the present invention is to increase the size of the device without increasing the size of the device.
It is an object of the present invention to provide a sputtering apparatus having a shutter that moves in and out of a processing space, which can obtain a relatively uniform film formation distribution over a large area.

[Means for solving the problem]

In order to achieve this object, the present invention holds a target plate made of a film-forming material, holds a target electrode as a cathode at the time of film formation, and a film-forming substrate opposite to the target plate in the processing space. A substrate holder that serves as an anode during film formation, a gas pipe that supplies a gas for sputtering to the processing space, a vacuum container that houses these, and an exhaust that is connected to the exhaust port of the vacuum container and exhausts the inside of the vacuum container. In a spattering apparatus including an apparatus and a shutter that moves in and out of the processing space from an exhaust port side, the sputtering device is arranged so as to be vertically movable between the substrate holder and the exhaust port, and rises during film formation and exhausts from the gas pipe. It is characterized in that a flow path adjusting plate is provided for adjusting the flow path resistance so that the gas for sputtering which flows toward the mouth uniformly flows in the processing space.

[Action]

The gas for spatula supplied from the gas pipe to the processing space flows toward the exhaust port in this processing space, but this gas flow for spatula is adjusted by the raised flow path adjusting plate to make it uniform in the processing space. Therefore, uniform plasma discharge occurs in the processing space, and uniform film formation is performed.

Further, the vertically movable gas flow path adjusting plate descends to provide a shutter movement space when the shutter is inserted into the processing space.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to the drawings in comparison with a conventional device.

FIG. 1 is a cross-sectional plan view of a sputtering device according to the present invention, and FIG. 2 is a vertical side view thereof.

In the vacuum container 1, the target plate 2 is held and the target electrode 3 serving as a cathode when performing the sputtering discharge, the earth shield 4a, and the substrate 5 which is opposed to these via the processing space 26 and is formed into a film, and the sputtering discharge is performed. Substrate holder 6, which serves as an anode when performing the above, the earth shield 4b, and the processing space.
A shutter 9 that goes in and out of the processing space 26 and divides the processing space 26 into two parts, a target electrode 3 side and a substrate holder 6 side, is accommodated. Gas for spatter is from gas cylinder 20 to gas pipe 8
Is supplied to the processing space 26 by means of the exhaust port 27 and the gate valve 18
It is exhausted by the cryopump 19 via the. The gas flow path adjusting plate 10 is disposed between the substrate holder 6 and the exhaust port 27 and in proximity to the substrate holder 6, and the gas flow path adjusting plate 10 is connected to the exhaust port 27 from the gas pipe 8.
The flow path resistance is adjusted so that the gas for sputtering that flows toward the inside of the processing space 26 flows uniformly in the processing space 26. The gas flow path adjusting plate 10 is supported by a drive device 11 so as to be movable up and down. .. The target electrode 3 and the substrate holder 6 are made of an insulating material, respectively.
It is insulated from the vacuum vessel 1 by 12, 13 and the high frequency power source 1 through the impedance matching boxes 14, 15.
Powered by 6,17.

In the above structure, the sputtering gas supplied from the gas pipe 8 to the processing space 26 during film formation is drawn by the cryopump 19 and flows in the processing space 26 toward the exhaust port 27.

The gas flow for spatter at this time is as shown by reference numerals 20a and 20b in FIG. 3 (a) in the sputtering device having no gas flow path adjusting plate 10, and the film thickness distribution is shown in FIG. 3 (b). ) Has a characteristic that the thickness gradually decreases along the direction of the gas flow for spattering as indicated by reference numeral 22a. However, in the case of the sputtering device provided with the gas flow path adjusting plate 10, the gas flow for spattering is as shown by reference numerals 20c and 20d in FIG. 4 (a), and the film thickness distribution is also shown in FIG. 4 (b). It is a significant improvement as indicated by reference numeral 22b.

On the other hand, as shown in FIG. 5, when exhaust ports 27a and 27b are provided on both sides of the processing space 26 and the cryopump 19 is used to exhaust gas through the gate valves 18a and 18b, the exhaust direction is The gas flow for spatters flowing in the processing space 26 in the directions indicated by arrows 21a and 21b in FIG. 6 (a) is indicated by reference numerals 20e to 20h.
It was found that the gas flow for spattering in the processing space 26 was not uniform and the film thickness distribution was not uniform as indicated by reference numeral 22c in FIG. Therefore, in the sputtering device of this type, the gas flow improving method such as the plasma CVD device described above cannot improve the film thickness distribution but only increase the size of the device.

The gas flow path adjusting plate is not limited to the one shown in the figure,
It is possible to employ those having various shapes and structures, for example, those having notches or through holes, those having a plurality of adjusting plates appropriately arranged in the gas flow path, and the like.

〔The invention's effect〕

As described above, the device of the present invention has a simple configuration in which the gas flow path adjusting plate is provided between the processing space and the exhaust port,
A relatively uniform film formation distribution can be obtained over a large area without increasing the size of the device, and the gas flow path adjusting plate can be moved up and down, so a shutter for entering and exiting the processing space is provided. The gas flow path adjustment can be realized in the sputtering apparatus.

[Brief description of the drawings]

FIG. 1 is a cross-sectional plan view of a sputtering device showing an embodiment of the present invention, FIG. 2 is a longitudinal side view thereof, and FIG. 3 (a) is an explanatory view of a gas flow for spattering of a conventional device, and FIG. 3 (b). ) Is its film thickness distribution chart, FIG. 4 (a) is an explanatory view of the gas flow for the sputtering of the sputtering device according to the present invention, FIG. 4 (b) is its film thickness distribution chart, and FIG. FIG. 6A is a vertical side view of the conventional apparatus, FIG. 6A is an explanatory view of the gas flow for the sputter, and FIG. 6B is a film thickness distribution view thereof. 1 ... Vacuum container, 2 ... Target plate, 3 ... Target electrode, 5 ... Substrate, 6 ... Substrate holder, 8 ... Gas pipe, 9 ... Shutter, 10 ... Gas flow path adjusting plate, 11 ...... Drive device, 19 …… Cryopump, 26 …… Process space, 27 ・ ・ ・
…exhaust port.

Claims (1)

(57) [Claims] 1. A target plate made of a film-forming material is held,
When the film is formed, the target electrode serving as a cathode and the target plate are opposed to each other with a processing space therebetween to hold the film formation base material,
A substrate holder that serves as an anode during film formation, a gas pipe that supplies a sputtering gas to the processing space, a vacuum container that houses these, and an exhaust device that is connected to the exhaust port of the vacuum container and exhausts the inside of the vacuum container. And a shutter that moves in and out of the processing space from the exhaust port side, the sputtering device is arranged so as to be vertically movable between the substrate holder and the exhaust port, and rises during film formation to exhaust from the gas pipe. The sputtering apparatus is provided with a flow path adjusting plate that adjusts the flow path resistance so that the sputtering gas that flows toward the chamber uniformly flows in the processing space.