Masking mechanism for film-forming device

Abstract

It comprises a mask (11) having a first, a second and a third action edge (11a, 11b, 11c), and a drive means for moving the mask (11) relative to a substrate (12) in a uniaxial direction (A) whereby moving the mask at a fixed rate of movement to cause the edges to successively act on an identical substrate region while successively applying different materials thereto forms thin films of three components successively with respective film thickness gradients oriented in three different directions mutually angularly spaced apart by an angle of 120° to allow these films to overlap, thereby forming a ternary phase diagrammatic thin film 13.

Description

TECHNICAL FIELD [0001] The present invention relates to a masking mechanism or device for a film forming apparatus for the purpose of making a thin film of compositions corresponding to a ternary phase diagram. BACKGROUND ART [0002] In recent years a number of new physical phenomena such as those of high temperature superconducting, giant magnetic resistance, high intensity fluorescence and catalysis have been discovered. Exploring a material and composition that develops such a physical phenomenon is carried out with a combinatorial film forming apparatus in order to reduce the time expended for material investigation. Using a combinatorial film forming apparatus allows forming a library of a group of materials possible of that developing on one substrate in one vacuum process and finding a new material and a new composition from the library or deriving a theoretical prediction from a specific character of the library. It is said that the use of a combinatorial film forming apparat...

AI Technical Summary

Benefits of technology

[0012] In view of the problems mentioned above it is an object of the present invention to provide a masking mechanism or device for a film forming apparatus that is capable of making a thin film of a ternary phase diagrammatic system without making the apparatus costly.

[0014] According to this device construction of the present invention, the first single action edge is positioned immediately ahead of a substrate region where a ternary phase diagrammatic thin film is to be formed. Then, the first single action edge may be moved at a selected rate of movement while the substrate region is vapor-deposited with a first material to produce a film thickness gradient of the first material. Next, the second single action edge is positioned immediately ahead of the substrate region to be formed with the ternary phase diagrammatic thin film. Then, the second single action edge may be moved at a selected rate of movement while the substrate region is vapor-deposited with a second material to produce a film thickness gradient of the second material. Next, the third single action edge is positioned immediately ahead of the substrate region to be formed with the ternary phase diagrammatic thin film. Then, the third single action edge may be moved at a selected rate of movement while the substrate region is vapor-deposited with a third material to produce a film thickness gradient of the third material. With the first, second and third action edges oriented by making 120° with one another, these film thickness gradients that then develop makes 120° with one another, thereby forming a thin film of the ternary phase diagrammatic system from component thin films. The masking mechanism for a film forming apparatus according to the present invention entails only a single mask and a means whereby the mask can only be moved in a single axial direction and hence requires a minimum of its volume and size. With the capability of forming a thin film of a ternary phase diagrammatic system, it no longer makes it necessary to raise the equipment cost.

[0020] According to this device construction of the present invention, the first single action edge is positioned immediately ahead of a region on a substrate where a ternary phase diagrammatic thin film is to be formed. Then, the first single action edge may be moved at a selected rate of movement while the substrate region is vapor-deposited with a first material to produce a film thickness gradient of the first material. Next, the second single action edge is positioned immediately ahead of the substrate region to be formed with the ternary phase diagrammatic thin film. Then, the second single action edge may be moved at a selected rate of movement while the substrate region is vapor-deposited with a second material to produce a film thickness gradient of the second material. Next, the triangular double action edge is positioned immediately ahead of the substrate region to be formed with the ternary phase diagrammatic thin film. Then, the triangular double action edge may be moved at a selected rate of movement while the substrate region is vapor-deposited with a third material to produce a film thickness gradient of the third material. In this case, the film thickness gradient produced by means of the triangular double action edge extends perpendicular to the direction in which the mask is moved and the film thickness gradients produced by means of the first and second single action edges make an angle of 120° with one another, thereby forming a thin film of the ternary phase diagrammatic system from component thin films. The masking mechanism for a film forming apparatus according to the second form of implementation of the present invention entails, here again, only a single mask and a means whereby the mask can only be moved in a single axial direction and hence requires a minimum of its volume and size. With the capability of forming a thin film of a ternary phase diagrammatic system, it does not make it necessary to raise the equipment cost.

[0022] The present invention also provides in a third form of implementation thereof a masking mechanism or device for a film forming apparatus, characterized in that: it comprises a single mask and a means for moving the mask relative to a substrate in a uniaxial direction; and the said mask has a triangular opening having a base side oriented in a said uniaxial direction, the said mask also having a side extending orthogonal to the said uniaxial direction; and the other two sides other than the base side of the said triangular opening and the said side orthogonal to the said uniaxial direction constitute a triple action edge, whereby selecting a rate of movement at which the said triangular opening is moved and a rate of movement at which the said side orthogonal to the said uniaxial direction allows a film thickness gradient to be produced in a particular direction determined by the rates of movement selected.

Problems solved by technology

In the prior method shown in FIG. 22(a), as the method requires the precise positioning among the substrate, the first mask 1 and second mask 2, however, this in turn requires spending considerable time, and in addition, as a result of which if an extremely large number of pixels are to be formed, then the film depositing conditions tend to change between the first and the last formed pixels.

Thus, for example, the substrate temperature distribution and atmospheric composition could change uncontrollably with the lapse of time, giving rise to the problem that reproducible data, or reliable data can no longer be obtained.

And, while in the prior method shown in FIG. 22(b) rotation makes it sufficient to position a given mask in less time-consuming, there the limitation in volume of the vacuum unit limits the number of masks that can be mounted and it is thus difficult to form an extremely large number of pixels with finely varied ratios of components.

It is extremely difficult, however, to include such a triaxially operating masking mechanism that must necessarily become considerably large in volume in an apparatus of this type used for material exploration, e.g., in a combinatorial film forming apparatus that makes it essential to be equipped with an ablation laser light lead-in unit, a target switching unit, a substrate heating laser unit and a reflection high-energy electron diffraction unit in a vacuum chamber.

This can be done, of course, by making the vacuum chamber in volume to an extent necessary to accommodate them, but so enlarging it requires augmenting the capacity of its vacuum pumping system correspondingly, thus making the apparatus highly costly.

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