JPS62222063A - Sputtering device - Google Patents

Abstract

PURPOSE:To prevent the heating of a substrate and a long-sized body and to prevent a decrease in the film forming velocity by providing an anode to surround the substrate when a thin film is formed on the substrate or the whole periphery of the long-sized body by the titled coaxial reverse magnetron-type sputtering device. CONSTITUTION:The periphery of the thin film forming substrate 1 is covered with the anode 2 consisting of a wire mesh made of stainless steel in the coaxial reverse magnetron-type sputtering device, and the assembly is arranged in the axial direction of a cylindrical target 3. Or the thin film forming long-sized body 11 is set in the axial direction of a cylindrical target 13, a water-cooled spiral Cu anode 12 is furnished around the body, or a long-sized body 21 to be coated with a film is arranged in the axial direction of a cylindrical target 22, and at least three water-cooled anodes 23 are arranged around the body. In this case, when a plane surrounding the periphery of the substrate is supposed, the ratio of the anode clearance area in the plane to the anode area is controlled to >=90%. The thin film of a target material is formed while preventing the heating of the substrate and the long-sized material and maintaining the film forming velocity at more than a specified value.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a sputtering device, and in particular, a sputtering device that applies a magnetic field in the axial direction of a cylindrical target and places a substrate or a long body near the central axis of the target. to discharge the
The present invention relates to a coaxial inverted magnetron type sputtering apparatus that forms a thin film on the substrate or elongated body by sputtering.

[Prior Art] and [Problems to be Solved by the Invention] In the process of improving sputtering technology, a classical coaxial magnetron type sputtering apparatus as conceptually shown in FIG. 5 has been developed. A classic coaxial inverted magnetron sputtering device is a classic coaxial magnetron sputtering device with the polarity reversed. In these classical magnetron-type sputtering devices,
Electrons can be moved in a circular direction perpendicular to the magnetic field, but they cannot be moved in a direction parallel to the magnetic field. Therefore, the ionization efficiency of the atmospheric gas cannot be reduced so much, and the film formation rate is slow.

In order to improve this drawback, a built-in magnet type sputtering apparatus and a shaded 4fA end plate type sputtering apparatus aSf were proposed as conceptually shown in FIGS. 6 and 7, respectively. These sputtering apparatuses can improve the ionization efficiency, but on the other hand, there is a problem in that the substrate generates a large amount of heat due to the impact of γ electrons. When the substrate generates heat, a problem arises in that the thin film formed thereon diffuses into the substrate. This is undesirable, for example for electronic devices. Furthermore, the substrate material p may become soft due to heat generation, and for example, elongation may occur in a long body under tension.

Therefore, today, planar magnetron type sputtering V apparatuses as conceptually shown in FIG. 8 are mostly used as sputtering apparatuses.

Although this device solves the above-mentioned problems, there are limitations on the substrate material that can be used. That is, this planar magnetron type sputtering apparatus is effective when continuous sputtering is to be performed on a film or the like. However, when attempting to uniformly form a thin film on the outer peripheral surface of a cylindrical or rod-shaped material, it becomes necessary to rotate the sample if a planar magnetron sputtering device is used. Therefore, a considerable amount of time is required to obtain a coating of a predetermined thickness over the entire surface of the sample.

Furthermore, even if a separate collector for gamma electrons is provided, the film thickness may become uneven in the area shaded by the collector, or the substrate may be heated by thermal radiation from the collector that generates heat, or radiation from the plasma may The light and heat may be large. Therefore, it has been impossible to perform continuous sputtering on materials with low heat resistance or thin wires.

Therefore, an object of the present invention is to form an iI film on the entire outer periphery of a substrate or an elongated body, to prevent heat generation of the substrate or elongated body, and to increase the film formation rate to a predetermined level or higher. It is an object of the present invention to provide a sputtering device that can be maintained at a high temperature.

[Means for Solving the Problems] and [Operations and Effects] A sputtering apparatus according to the present invention applies a magnetic field in the axial direction of a cylindrical target, places a substrate near the central axis of the target, and performs discharge processing. The present invention is a coaxial inverted magnetron type sputtering apparatus for forming fljl on the substrate by sputtering, and is characterized in that an anode is provided so as to surround the periphery of the substrate.

In addition, another sputtering apparatus according to the present invention applies a magnetic field in the axial direction of a cylindrical target, continuously supplies a long body near the central axis of the target to cause discharge, and records IVI by sputtering. This is a coaxial inverted magnetron type sputtering apparatus for forming a thin film on a long body, and is characterized in that an anode is provided to surround the long body.

Since the anode is provided so as to surround the substrate or the elongated body, γ electrons are absorbed by the anode, and the number of γ electrons colliding with the substrate or the elongated body is reduced. Therefore, it is possible to prevent a significant temperature rise or damage to the substrate or the elongated body due to the impact of γ electrons.

When considering a plane that passes through the anode and extends in a direction parallel to the central axis of the cylindrical target and surrounds the substrate or elongated body, the [inter-anode gap plane VJ/anode area] in this plane The larger the ratio, the greater the degree of heating of the substrate or elongated body, and the faster the film formation rate.

In order to prevent the upper temperature limit of the substrate or elongated body, the ratio of "inter-anode gap area/anode area" may be reduced, but this will slow down the film formation rate.However, the inventor of the present application , found the following.That is, although the film formation rate increases with the ratio of "gap area between anodes/anode area", the amount of heat incident on the substrate or elongated object is larger than the surrounding area of the substrate or elongated object. Even if the above ratio is a large value, it will be reduced if there is an anode surrounding it.In order to prevent heating of the substrate or elongated body and maintain the film formation rate above a predetermined level. For this purpose, it is preferable to set the above-mentioned "gap area between anodes/anode area" to 90% or more.In this way, the film forming rate can be equivalent to that of a normal coaxial inverted magnetron type sputtering system. can be obtained.

Atoms and molecules sputtered from a cylindrical target are scattered in many directions, so even if the anode is provided to surround the substrate or elongated object, a uniform film will not be formed on the outer peripheral surface of the substrate or elongated object. thickness can be obtained.

Various types of anode can be considered as the anode that surrounds the substrate or the elongated body. For example, as shown in FIG. 1, the periphery of the substrate 1 may be covered with an anode 2 made of stainless steel wire mesh.

In addition, in the figure, 3 is a target and 4 is a *ra stone.

Further, as another embodiment, a cylindrical anode that is approximately concentric with the cylindrical target and has a large number of small holes is also considered. However, the inventor of the present application has discovered that when a wire mesh anode or a cylindrical anode is used, there is a risk that the anode itself may be heated significantly. In that case, not only is the anode significantly damaged, but there is also the risk that the substrate or elongated body may be heated by the radiant heat from the heated anode.

Therefore, it is preferable to provide an anode having a cooling function. FIG. 2 shows such a preferred anode.

In the figure, 11 is a continuous elongated body, 13 is a target, and 14 is an electromagnet. As an anode, a spiral copper tube 12 extends spirally in the direction of the central axis of the cylindrical target 13 and has cooling water passed inside.
is used.

FIG. 3 also shows an example of an anode in a preferred embodiment. In the figure, 21 is an elongated body that is continuously supplied, and 22 is a cylindrical target.

Three pipes 23 that extend linearly parallel to the central axis of the cylindrical target 22 and allow cooling water to pass therethrough are used as anodes surrounding the elongated body 21. These three pipes are positioned in a circular orbit 24 centered on the central axis of the cylindrical target 22 so as to surround the elongated body 21. Even if the number of pipes 23 is one or two, it is possible to reduce the temperature rise of the elongated body 21 to some extent, but this is insufficient. Therefore, if an anode of the embodiment shown in FIG. 3 is used, at least 63 pipes would be required.

As described above, the present invention is a coaxial inverted magnetron type sputtering apparatus, and is characterized in that an anode is provided so as to surround the periphery of the substrate. The film formation rate can be maintained at a predetermined level or higher.

The present invention, which has such effects, can be effectively used for sputtering electronic devices, materials that soften due to high heat, and elongated bodies such as wires and strips that are supplied under tension.

[Example] 1192 Sputtering was performed using the apparatus shown in FIG.

A TI4 wire was used as the elongated body 11, and the temperature at the center was measured with a thermocouple. As target 13, 99.
Made of 99% nickel, inner diameter 1001φ, outer diameter 11
A cylinder with a diameter of 01IIlφ and a length of 500II1m was used. A 99.99% nickel cathode plate is attached to each end of the cylindrical target. The anode 12 is made from a steel pipe with an outer diameter of 5 mm and an inner diameter of 3 II 1 m, and has a diameter of 6011 mm.
A spiral steel pipe of IIlφ was used. The magnetic field is set at 260°C at the center of the cylindrical target using an externally wound coil.
The voltage was applied so that the voltage was ersted.

Then, the film formation rate and the temperature of the elongated body were measured while varying the ratio of "anode gap area/anode area".

Note that the sputtering conditions were as follows.

Ultimate vacuum: 2X 10-' Torr gas pressure:
The results obtained using lX10-'' Torr input power: 400 Watt D are shown in FIG. As is clear from FIG. 4, if the ratio of "anode gap surface M/anode gap surface" is set to 90% or more, temperature rise of the elongated body can be prevented and the film formation rate can be kept above a specified level. It is recognized that it can be maintained.

Yo1"LL The outer surface of a cylindrical target made of copper with an inner diameter of 300 mmφ is water-cooled, and inside it is 10 mm + x 100 mm x 1 f.
Sputtering was performed by installing an aluminum plate having a thickness of flI11. A coil was provided around the outer circumference of the target, and a magnetic field was applied to the center of the target at 400 oersteds.

Note that the sputtering conditions are as follows.

Ultimate vacuum: 2X 10-' Torr Gas pressure: l
X10-'' Torr Input power: 600 Watt When the above operation was performed for 10 minutes, the substrate was heated to 350°C.

Two rod-shaped I! parallel to the central axis of the cylindrical target. l
When the same operation was performed with a pole installed, the upper temperature limit of the substrate was up to 320°C.

Next, when we installed three rod-shaped anodes to surround the substrate and repeated the same operation, the temperature of the substrate increased by 200°C.
Until now.

[Brief explanation of drawings]

FIG. 1 is a diagram conceptually showing an embodiment of the present invention. FIG. 2 is a diagram conceptually showing another embodiment of the invention. FIG. 3 is a diagram conceptually showing still another embodiment of the present invention. Figure 4 shows the growth IIQ speed and substrate (
FIG. 3 is a diagram showing the relationship between the elongated body)'fiA degree and "anode gap area/anode space". FIG. 5 is a diagram conceptually showing a classical coaxial magnetron type sputtering apparatus. FIG. 6 is a diagram conceptually showing a built-in magnet type sputtering apparatus. FIG. 7 is a diagram conceptually showing a cathode plate type sputtering apparatus. FIG. 8 is a diagram conceptually showing a planar magnetron type sputtering apparatus. In the figure, 1 is a substrate, 2 is an anode made of stainless steel wire mesh, 3 is a target, 4 is an electromagnet, 11 is a long body, 1
2 is spiral copper? ! An anode, 13 a target, 14 an N11 stone, 21 a long body, 22 a target, 23 a pipe as an anode, and 24 a circular orbit. ,

Claims (8)

[Claims] (1) Applying a magnetic field in the axial direction of a cylindrical target and disposing a substrate near the central axis of the target to cause discharge;
A coaxial inverted magnetron type sputtering apparatus for forming a thin film on the substrate by sputtering, characterized in that an anode is provided so as to surround the periphery of the substrate.
Sputtering equipment. (2) the anode extends spirally in the direction of the central axis;
The sputtering apparatus according to claim 1, which is a spiral tube through which cooling water is passed. (3) the anode extends linearly parallel to the central axis;
and at least three pipes through which cooling water passes, each of the pipes being positioned in a circular orbit around the central axis so as to surround the substrate. The sputtering device described in . (4) When considering a plane that passes through the anode, extends in a direction parallel to the central axis, and surrounds the periphery of the substrate, "anode gap area/anode area" in this plane is 90% or more. A sputtering apparatus according to any one of claims 1 to 3. (5) A coaxial inverted magnetron that applies a magnetic field in the axial direction of a cylindrical target, continuously supplies a long body near the central axis of the target to cause discharge, and forms a thin film on the long body by sputtering. A sputtering apparatus characterized in that an anode is provided so as to surround the elongated body. (6) the anode extends spirally in the direction of the central axis;
The sputtering apparatus according to claim 5, which is a spiral tube through which cooling water is passed. (7) the anode extends linearly parallel to the central axis;
and at least three pipes through which cooling water passes, each of the pipes being positioned in a circular orbit around the central axis so as to surround the elongated body. The sputtering apparatus according to item 5. (8) When considering a plane that passes through the anode and extends in a direction parallel to the central axis and surrounds the elongated body, the "inter-anode gap area/anode area" in this plane is 90%.
The sputtering apparatus according to any one of claims 5 to 7, which is the above.