JPH0342035Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a magnetron sputtering device that includes a frame-shaped shield member around a target surface facing a substrate.

[Prior art]

Magnetron sputtering equipment creates a magnetic field orthogonal to the electric field to confine the plasma generated in a vacuum in the space near the target, and can produce particles with larger and more uniform particle sizes than vacuum evaporation. It is possible to stably obtain various compositions by selecting the target material, it is possible to form films of silicide, refractory metal, etc., there is no impact on the substrate because the electrons are confined near the target, and Since the area is large and the energy of the sputtered atoms is large, sputtering atoms have advantages such as high mobility after adhesion to the surface and excellent step coverage, and various mass production devices have been developed and are now widely used.

By the way, in such a magnetron sputtering apparatus, a frame-shaped shield member is conventionally provided around the target surface facing the substrate to prevent sputter atoms from adhering and depositing on parts other than the substrate. . This shield member is
Usually made of stainless steel with a smooth surface,
Its ends are placed over the outer edges of the target surface. However, when sputtering is continued in such a configuration, sputter atoms are deposited on the vertical smooth end face of the shield member near the target surface, and are further peeled off and fall onto the target surface. This may cause impurities to be mixed in, sputtering may become unstable, or the scattered flakes may adhere to the substrate, causing pinholes in the film formed on the substrate.

[Summary of the idea]

The present invention was developed in view of the above circumstances, and its purpose is to prevent defects in film formation caused by the peeling off and scattering of deposits that occur at the ends of the shield member, and to An object of the present invention is to provide a magnetron sputtering device capable of stabilizing the characteristics of a film formed thereon.

In order to achieve this purpose, the present invention
The end of the shield member near the target surface is roughened and tapered, and the shield member is configured such that the non-erosion area at the outer edge of the target surface is covered by the shield member. The inner contour part is formed.

Hereinafter, the present invention will be explained in detail using the illustrated embodiments.

〔Example〕

FIG. 1 is a sectional view of a main part showing an embodiment of the present invention. This embodiment is a so-called planar type DC magnetron sputtering apparatus, in which a target 2 made of, for example, chromium is placed in the center of a vacuum chamber 1. In the illustrated example, the target 2 is placed on a base material 3 made of copper, but
If the target has a sufficient area, the base material 3 may be omitted. On the back side of the target 2, a columnar magnet 4a and a ring-shaped magnet 4b surrounding the columnar magnet 4a are arranged with the target 2 side as an S pole and an N pole, respectively. Further, a frame-shaped shield member 5 is arranged around the surface side of the target 2. The shield member 5 is arranged so that its end portion covers the outer edge of the target 2, and prevents spatter atoms from adhering to a substrate other than a substrate (not shown) arranged opposite to the target surface. In the embodiment, it also serves as an electrode, and a DC voltage is applied with the shield member 5 side being positive and the target 2 side being negative.

The target 2 has a rectangular flat plate shape as shown in FIG. 2, and on the outside of its surface, lines of magnetic force 11 are drawn in an arc shape, coming out from an annular magnetic pole arranged on the back surface and entering a columnar magnetic pole at the center. As a result, an orthogonal electromagnetic field space is created in the space between the pair of magnets, where the lines of magnetic force and the lines of electric force due to the DC voltage are perpendicular to each other, and the plasma generated in a vacuum is created by the arcuate magnetic lines of force in a donut-shaped region 12. to be confined in The electron's trajectory is 1
As shown by 3, the plasma undergoes cycloidal movement inside the plasma region 12 to promote the generation of argon ions, thereby increasing the density of the plasma and improving the sputtering efficiency. Therefore, target 2 has a third
As shown in the figure, an erosion region 21 corresponding to a sputter region and non-erosion regions 22 and 23 at the center and outer edges are formed.

Here, the shield member 5 is made of aluminum, and its surface is roughened. Therefore, compared to the smooth surface of conventional stainless steel, the spatter atoms adhere more firmly and do not easily peel off and fall onto the target, or scatter and adhere to the substrate. In particular, in the illustrated example, the end portion 5a of the shield member 5 close to the surface of the target 2 is formed into a tapered shape.
The attached deposits are structured to be more difficult to peel off. That is, in the conventional device having an end face perpendicular to the target surface as shown by the broken line in FIG. 1, a large amount of spatter atoms adhered to this end face and easily peeled off, whereas in this example, If this end face is sloped, it will adhere to the slope on average and will be difficult to peel off.

Further, in this embodiment, as shown in FIG. 4, the inner contour of the frame-shaped shield member 5 is oval, and is shaped to completely cover the non-erosion area 23 at the outer edge of the target 2. Conventionally, the boundary between the non-erosion area 23 and the erosion area 21 is oval, whereas the shield member 5 has a rectangular outline as shown by the broken line in FIG. 4. Although a non-erosion area 23a not covered by the shield member 5 as shown remains, such a non-erosion area 23a
The spatter atoms attached to the shield member 5 are similar to those once attached to the shield member 5, and when they fall into the erosion region 21 and are sputtered again, or are scattered and adhered to the substrate, they are originally removed from the erosion region 21. This degrades the properties of the film on the substrate that should be produced only with directly sputtered atoms.
Therefore, in this embodiment, as described above, by completely covering the non-erosion region 23 at the outer edge, spatter from the non-erosion region is reduced and the properties of the film are stabilized.

Although the above explanation has been made using a planar type DC magnetron sputtering device as an example, the present invention is not limited to this, but has a structure in which a frame-shaped shield member is provided around the target surface facing the substrate. If so, it goes without saying that the present invention can be similarly applied to other types of magnetron sputtering devices.

To roughen the aluminum surface, there are methods such as sandblasting, chemical etching, shot peening, etc. In this example, the sandblasting method is used, and the surface roughness is from several tens of μm to several hundred μm. Preferably within the range, in this example 50 μm ~
There is a mixture of about 500μm. In addition to aluminum, relatively soft metals such as copper and brass can be used when sandblasting is used as a surface roughening method, and iron and stainless steel can be used in addition to the above metals when chemical etching is used. Alternatively, a relatively hard metal such as a nickel alloy containing chromium, copper, iron, etc. can be used.

Soft metals are generally preferred for roughening and tapering, and aluminum used in this example has good conductivity and is inexpensive, making it a practical material for shielding members.

[Effect of idea]

As explained above, according to the present invention, at least the surface of the end portion of the shield member close to the target surface is roughened and this end portion is formed in a tapered shape, thereby preventing spatter adhering to the surface. Since the atoms do not easily peel off, it is possible to prevent deterioration of film properties caused by the peeled off deposits being attached to the substrate either directly or by being sputtered again.

Furthermore, by forming the inner contour of the shield member so that the non-erosion area at the outer edge of the target surface is covered by the shield member, spatter from the non-erosion area is reduced and the film formed on the substrate is Characteristics can be stabilized.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of essential parts showing an embodiment of the present invention;
FIG. 2 is a diagram for explaining the principle of sputtering, FIG. 3 is a diagram for explaining the erosion area and non-erosion area that occur on the target,
FIG. 4 is a diagram for explaining the contour shape of the shield member. 1... Chamber, 2... Target, 4a, 4
b... Magnet, 5... Shield member, 5a... End, 11... Lines of magnetic force, 12... Plasma region, 2
1... Erosion area, 22, 23, 23a...
...non-erosion area.

Claims (1)

[Scope of utility model registration request] In a magnetron sputtering device including a frame-shaped shield member around a target surface facing a substrate, at least the end of the shield member near the target surface is configured to have a rough surface, and this end is tapered. A magnetron sputtering apparatus characterized in that the inner contour of the shield member is formed such that a non-erosion region at the outer edge of the target surface is covered by the shield member.