JPH02243760A - Electrode structure - Google Patents

Abstract

PURPOSE:To effectively cool an electrode by introducing gas into the gap between the electrode and a holding member. CONSTITUTION:An electrode (target) 2 is held by a holding member 5 so that the electrode 2 can be cooled by introducing gas into the gap between the electrode 2 and the holding member 5 through a gas introducing pipe 20. The rear side of the electrode is stepped and at least two regions i.e. the periphery of the electrode and the stepped part are adhered to the opposite face of the holding member by thermal expansion. A clamping member for clamping the holding member at the rear side of the electrode is fitted. Heat exchange be tween the opposite faces of the electrode and the holding member can be effi ciently carried out.

Description

[Detailed description of the invention] [Object of the invention] (Industrial application field) The present invention is used as a target of a sputtering device, an electrode of an X-ray source, an ion source, a plasma source, etc., and cooling is essential during use. The present invention relates to an electrode structure.

(Prior art) In general, sputtering equipment uses an airtight container into which ionizing sputtering gas is introduced, and ions in the plasma collide with a target, which is a negative voltage electrode, to perform sputtering. A thin film is formed on the surface of a sample such as a wafer.

In this type of sputtering equipment, if the temperature of the target exceeds, for example, 150°C due to the temperature rise during plasma generation, although it also depends on the type of the base material of the target that is the electrode, various adverse effects will occur on the target etc. It was supposed to inhibit the formation of thin films. In particular, this has been a major obstacle when attempting to supply more power to the target in order to increase sputtering speed with the aim of improving productivity.

Therefore, conventionally, the target is set at a predetermined temperature, for example, 10
The target is cooled so that the temperature does not exceed 0°C.

Conventional cooling methods for this target include a direct cooling method in which a cooling medium is circulated along a holding member with good thermal conductivity that supports the target, and a cooling jacket placed on the side of the target with cold water pipes inside. There was an indirect cooling method with a

(Problems to be Solved by the Invention) A holding member is fastened to the target in the plasma erosion area.

In this fastened state, as the target is heated as sputtering progresses, the target may warp due to thermal expansion and the adhesion between the back surface of the target and the opposing surface of the holding member may deteriorate. there were. This deterioration in adhesion is due to the fact that heat cannot be efficiently radiated because the target is cooled using heat conduction with the holding member, and therefore the target cannot be effectively cooled.

This kind of problem is not limited to targets, which are electrodes in sputtering equipment, but especially the electrodes themselves are worn out, and the electrodes are supported removably on a holding member and are designed to suppress temperature rise during use. Similar problems have arisen with various types of electrodes in which cooling is performed via a holding member.

Therefore, an object of the present invention is to provide an electrode structure that can improve heat exchange between an electrode and a holding member that holds it, and can significantly reduce the temperature gradient inside the electrode. be.

[Structure of the Invention] (Means for Solving the Problems) The present invention is an electrode structure in which an electrode is coolably held by a holding member, and is characterized by the following structure.

That is, in the first invention, gas is introduced between the electrode and the holding member. In the second invention, a stepped portion is formed on the back side of the electrode, and at least two areas, the peripheral edge of this electrode and the peripheral edge of the stepped portion, are brought into close contact with the opposing surfaces of the holding member by thermal expansion. . A third aspect of the present invention is that a clamp member is provided to clamp the holding member on the back surface side of the central portion that is not exposed to the surface of the electrode.

(Function) In the first invention, a gas is introduced between the electrode and the holding member. For example, by introducing an inert gas, the space between them can be made to have a relatively high pressure.

In other words, since the degree of vacuum in the space between them can be lowered, by utilizing the thermal circulation of the gas, the heat generated within the electrode can be conducted to the holding member, and as a result, the heat between the electrode and the holding member is reduced. Exchange can be facilitated. Even if the electrode warps, it can be absorbed in space.

In a second aspect of the invention, at least two regions, the peripheral edge of the electrode and the peripheral edge of the stepped portion formed on the back side of the electrode, are brought into close contact with opposing surfaces of the holding member.

Moreover, since this adhesion is guaranteed by thermal expansion of the electrode or holding member, the adhesion can be maintained at all times during use due to the temperature rise during sputtering, and the adhesion can be maintained at all times through the above two areas. This can promote heat exchange between the electrode and the holding member. Furthermore, cooling of the outer edge of the electrode can be ensured by the close contact between the peripheral edge of the electrode and the holding member, while cooling of the inner part of the electrode can be ensured by the step on the back side of the electrode and the holding member. The temperature gradient from the center of the electrode to the outer edge can be reduced.

In the third aspect of the invention, clamping of the central part of the electrode where warping is likely to occur particularly when the temperature rises during sputtering is carried out on the back side of the central part of the electrode. Therefore, even if the temperature of the electrode itself increases, the central part of the electrode is held by the clamp member to the holding member, so no warping occurs and the adhesion of this area can always be ensured. Heat exchange with the holding member near the center of the electrode can be maintained.

(Example) Hereinafter, an example in which the first to third inventions are applied to a sputtering apparatus will be specifically described with reference to the drawings.

FIG. 1 shows a plate magnetron type sputtering apparatus as an example of a sputtering apparatus, in which a semiconductor wafer 1 and a target 2 are placed facing each other in a vacuum container (not shown). The semiconductor wafer 1 is supported by a sample stage 4 that includes a wafer heating mechanism 3.

The target 2 placed above the wafer 1 is
It is held by a holding member 5. This target 2
The base material is selected depending on the material to be formed on the wafer 1, such as aluminum.

Silicon, tungsten, titanium, molybdenum.

It is made of chromium, cobalt, nickel, etc., or an alloy made of these materials, and in some cases, a material with poor thermal conductivity such as sintered metal is also used. Its shape may also be a stepped cross-section, a disc, a cone, a square plate, a pyramid, or the like. A negative DC voltage is applied to this target 2, which constitutes a cathode electrode.

Further above the holding member 5, a base 6 is provided to support the holding member 5 and to rotatably support a magnet 10, which will be described later. A hollow cylindrical portion 6a is formed in the center of the base 6, and its lowermost end is in contact with the holding member 5. A bearing 7 is arranged around the cylindrical portion 6a, and a rotary disk 8 is rotatably supported by the bearing 7.

The magnet 10 is fixed to an eccentric position of the rotating disk 8. On the other hand, a magnet rotation motor 11 is fixed to the upper surface of the base 6.
A first gear 12 is fixed to the first output shaft. Further, a second gear 13 is fixed concentrically with the rotating disk 8, and the first and second gears 12 and 13 mesh with each other. As a result, the magnet rotation motor 11
By driving the magnet 10, this rotational output is transmitted to the rotating disk 8 via the first gear 12 and the second gear 13, and the magnet 10 can be rotationally driven.

The holding member 5 holds the target 2 in a coolable manner, and for this purpose, a plurality of cooling jackets 15 are arranged inside the holding member 5. By circulating a cooling medium, for example, cooling water, in this cooling jacket 15, the holding member 5 is cooled, and heat exchange between this holding member 5 and the target 2 suppresses the temperature rise of the target 2 when plasma is generated. It is supposed to be suppressed.

An anode electrode 17 is provided around the target 2 with an insulator 16 interposed therebetween, and a shutter 18 is further provided to block the gap between the wafer 1 and the target 2 as necessary. The shutter 18 can be driven by a shutter drive mechanism 19.

In order to carry out the first invention, in the present embodiment, the device penetrates the center of the cylindrical portion 6a of the base 6, and further penetrates the center of the holding member 5 to face the back side of the target 2. Alternatively, it has a plurality of gas introduction pipes 20, for example, one gas introduction pipe.

This gas introduction pipe 20 connects the holding member 5 and the target 2.
A sealed gap between the back surface and the back surface is set to a pressure of, for example, several 100 mTorr or more using an inert gas such as argon or helium.

Next, a configuration example for carrying out the first and second aspects of the invention with respect to the above-mentioned embodiment device will be described with reference to FIG. 2 as well.

The target 2 is formed in the shape of a stepped disc with one or more steps, for example, a large diameter portion 21 having a sputtering surface, and a small diameter portion protruding from the center of the back side of the large diameter portion 21. It is composed of a section 22. This small diameter portion 22
Although it is formed into a convex shape, it may be formed into a concave shape. Note that the diameter of the peripheral edge 21H of the large diameter portion 21 is 11, and the diameter of the inner peripheral surface 24H of the small diameter hole 22a is 12. On the other hand, the holding member 5 for holding the target 2 has a stepped hole shape, with a large diameter hole 24 corresponding to the large diameter part 21 of the target 2 and a small diameter hole 25 corresponding to the small diameter part 22. It has In addition, the diameter of the inner circumferential surface 24a of the large diameter hole 24 is 13
The diameter of the inner circumferential surface 25a of the small diameter hole 25 is 14.

Regarding the sizes of the target 2 and the holding member 5, the relationship ll-14 is as follows at room temperature.

! , <13.12<1!4 Here, the diametrical gap between the large diameter portion 21 and the large diameter hole 24 and the diametrical gap between the small diameter portion 22 and the small diameter hole 22 are set as follows. has been done.

That is, since the target 2 thermally expands due to temperature rise during plasma generation, the thermal expansion length of the large diameter portion 21 in the diametrical direction is greater than the length of the large diameter portion 21. The gap is approximately the same as the gap in the diametrical direction of the large diameter hole 24.

Similarly, the length of thermal expansion of the small diameter portion 22 due to thermal expansion of the target 2 is the length of the small diameter portion 22. The gap is approximately the same as the gap in the diameter direction of the small diameter hole 25.

Therefore, due to thermal expansion of the target 2, the large diameter portion 21
The peripheral edge portion 21a of the large diameter hole 24. and the peripheral edge portion 22a of the small diameter portion 22 expand, respectively. The inner circumferential surfaces 24a and 25a of the small diameter hole 25 are in close contact with substantially the same degree of sealing. Note that under the same temperature, the large diameter portion 21
Since the expansion length of the small diameter portion 22 is different from that of the small diameter portion 22, the inner peripheral surface 24 of the hole portion opposing these peripheral portions 21a and 22a and
The gap distances between a and 25 a are different.

Next, an example of a configuration for implementing the third invention using the apparatus of the embodiment described above will be described.

In this embodiment, the central rear surface side of the target 2, where the temperature rises rapidly, is clamped to the holding member 5. This clamp is, for example, a peripheral portion 2 of the small diameter portion 22 of the target
2H are formed with locking pins 23, 23 that project outward in the diametrical direction at opposing positions. The clamp may be a threaded connection as shown in FIG.

On the other hand, on the bottom surface 24b of the large diameter hole 24 of the holding member 5,
The locking pin 2 communicates with opposing positions of the small diameter hole 25.
3.23 insertion slit of a predetermined depth into which 26.
26 is provided, and this insertion slit 26.26
It has a locking groove 27° 27 formed of a lateral groove that communicates with the lower end side and extends in the same rotational direction. As a result,
The small diameter portion 22 of the target 2 is inserted into the small diameter hole 2 of the holding member 5.
5 so that the locking pin 23.23 is inserted into the insertion slit 26.26, and then the target 2 is rotated by a predetermined angle in a direction in which rotation is permitted. A locking pin 23.23 can be arranged at the end of the locking groove 27.27 of the retaining member 5.

Next, the effect will be explained.

In order to perform sputtering with this sputtering apparatus, the degree of vacuum in a vacuum chamber (not shown) in which the wafer 1 and target 2 are placed is adjusted to, for example, 10-1 to 10-3 Torr while supporting each wafer 1 and target 2. Pull. next,
The degree of vacuum in the vacuum container is 10-5 to 10-'Torr.
A high vacuum is applied to the table, and then a sputtering gas such as Ar gas is introduced into the vacuum container, and the inside of the vacuum container is
Set to O-3 Torr level. Here, when a negative voltage is applied to the target 2, plasma is formed on the sputtering surface side of the target 2, and furthermore, a plasma is formed on the sputtering surface side of the target 2.
By rotating the magnet 10 on the back side of the plasma ring 30, it is possible to form a plasma ring 30 in which this plasma is confined by a magnetic field. This plasma ring 30
The formation of the ionization rate improves the ionization rate, and sputtering is performed in a predetermined erosion area on the sputtering surface of the target 2.

Here, if the deposition rate on the wafer 1 is increased, the surface temperature of the target 2 will rise significantly, and if it exceeds a predetermined temperature, proper thin film formation will be hindered. Therefore, it is necessary to effectively cool the target 2, and by applying the first to third aspects of the present invention, the apparatus of this embodiment can effectively cool the target 2 by acting in three directions. It has become.

First, the operation of the gas introduction pipe 20, which is a configuration example of the first invention, will be explained.

The target 2 is cooled by dissipating heat through the holding member 5 to a cooling jacket 15 built into the holding member 5. It is preferable that the surface has the largest contact area and that this large contact area is used to radiate heat from the target toward the holding member 5 side. However, in order to secure almost the entire surface of the target 2 as an erosion area, it is difficult to adopt a fastening method that tightly adheres the above contact surfaces. It was difficult to use it as a surface.

Therefore, in this embodiment, an inert gas such as argon gas is supplied between the back surface of the target 2 and the opposing surface of the holding member 5 from the gas introduction pipe 20 facing between the back surface of the target 2 and the opposing surface of the holding member 5. It has been introduced. As a result, by filling the space formed between the two members with argon gas, the pressure within this space can be made relatively high. In other words, this means that the degree of vacuum in this internal space becomes low, and as a result, if there is a temperature difference between the two members, the heat of target 2 will be retained by the thermal circulation of the gas filled in this internal space. It becomes possible to efficiently transmit the information to the member 5.

In this way, the inert gas is introduced into the target 2. By filling the space of the holding member 5, efficient heat exchange can be carried out by utilizing the wide contact surface between the two, without having to ensure adhesion between the two, and the target 2 can be efficiently exchanged. It becomes possible to cool well.

Note that the introduction of such an inert gas can promote the cooling effect, especially when a high melting point material with poor thermal conductivity (for example, tungsten silicide, molybdenum silicide, tantalum silicide, titanium silicide, etc.) is used as the material of the target 2. It is also effective for

Next, a cooling effect according to a configuration example of the second invention will be explained.

The diameters 1, . 12 is a large-diameter hole 24. of the holding member 5 facing thereto. Although the diameters of the inner circumferential surfaces 24 a and 25 a of the small-diameter holes 25 are smaller than the diameter '3+14 at room temperature, the target 2 can be adjusted by applying a negative voltage to the target 2 and generating plasma.
When the temperature rises, the large diameter portion 21. The small diameter portion 22 thermally expands, and the respective peripheral edges 21a and 22a come into close contact with the opposing inner peripheral surfaces 24a and 25a of the holding member 5. The adhesion in this region is not impaired during sputtering because the temperature of the target 2 is maintained at a predetermined temperature or higher, and therefore the peripheral edges 21g, 22 of the target 2 are not deteriorated.
It becomes possible to carry out efficient heat exchange at the contact surface between g and the inner circumferential surfaces 24 a, 25 a of the holding member 5. Moreover, the region where the large diameter portion 21 of the target 2 contacts the holding member 5 is used to radiate heat from a region relatively close to the outer peripheral region of the target 2;
The contact portion of the small diameter portion 22 is used to radiate heat from the center region of the target 2 to the holding member 5. Therefore, the thermal gradient in the diametrical direction of the target 2 can be efficiently removed, and the heat in the center of the target 2, which has been difficult to dissipate in the past, can be efficiently dissipated.
It is possible to reliably prevent the occurrence of warpage in this portion.

Therefore, it is possible to maintain the flat part of the target 2 in contact with the holding member 5, and by also employing the configuration example of the first invention described above, more effective cooling of the target 2 can be expected. . In addition, as in the structure of the target 2 of this embodiment, forming a stepped portion has the effect of increasing the heat dissipation effect in the central region of the target 2, but in addition, compared to a conventional flat plate-shaped target, the stepped portion is Another advantage is that by ensuring a contact area around the periphery of the parts, a wider cooling surface can be secured.

Furthermore, by forming the target 2 into a stepped shape as described above, the following effects can be achieved. That is, the large diameter portion 21. of the target 2. By promoting cooling at the peripheral edges 21a and 22a of the small diameter portion 22, it is possible to reduce the thickness of the cooling region 5a (see FIG. 1) of the holding member 5 that contacts the back surface of the large diameter portion 21. can.

Therefore, without changing the distance between the target sputtering surface and the magnet 10, it is possible to ensure that the wall thickness of the large diameter portion 21 of the target 2 is thicker by the amount that the thickness of the cooling area 5a is thinner. It becomes possible to extend the life of the target 2.

Furthermore, as shown in FIG. 1, cooling can be effectively achieved by providing a cooling jacket at a location on the back side of the center of the target 2 and at a location corresponding to the peripheral edge of the target 2. Conventionally, it has been necessary to adopt a configuration in which a cooling medium is circulated over the entire back surface of the target and the magnet 10 is rotated in the cooling medium. In this embodiment, since it is only necessary to arrange the magnet 10 as shown in FIG. 1, it is possible to expose the magnet 10 close to the back surface of the target 2 and the structure for rotationally driving this magnet 10 to the atmosphere. Therefore, reliability can be improved without corrosion caused by cooling water or the like.

Next, a cooling effect according to a configuration example of the third invention will be explained.

In this embodiment, the above-mentioned adhesion is further ensured by clamping the center side of the back surface of the target 2 to the holding member 5. That is, when the locking pin 23° 23 formed on the small diameter portion 22 of the target 2 is locked in the locking groove 27.27 of the holding member 5, the target 2
This clamp can be maintained at all times unless it rotates in a predetermined direction. In this way, by constantly holding the center side of the back surface of the target 2 against the holding member 5, it is possible to mechanically prevent warping of the center part of the target 2, where the temperature rises particularly markedly, by using this clamp. . In particular, in the case of this embodiment, since the peripheral edge of the target 2 is configured to come into close contact with the opposing inner circumferential surface of the holding member 5 due to its thermal expansion, if the target 2 attempts to further expand due to heat, The only place for escape is the central part of the target 2, but by holding this part with the above-mentioned clamper, it is possible to prevent any deformation of the target 2 that would impair its adhesion with the holding member 5. Become.

Incidentally, since the damper means is not exposed on the sputtering surface side of the target 2, it is also excellent in that it does not reduce the erosion area on the target 2.

Although the cooling effect of the target 2 according to one configuration example of each invention has been individually explained above, it goes without saying that more effective cooling of the target 2 can be ensured by the synergistic effect of the configuration examples of each of these inventions. As a result of being able to effectively cool the target 2 in this way, it becomes possible to further improve the deposition rate of the target 2 even though the equipment has the same cooling capacity as the conventional equipment.

Next, replacement of the target 2 with the holding member 5 in the above embodiment apparatus will be explained.

This target 2 needs to be replaced when its life reaches the end due to sputtering. When the target 2 reaches a predetermined temperature or lower, the peripheral edges 21a and 22a of the target 2 will be separated from the opposing inner peripheral surfaces 24a and 25a of the holding member 5 due to thermal contraction. After that, when the target 2 is rotated, the locking pin 2 protrudes from the small diameter portion 22 of the target 2.
3.23 is stopped at a position facing the insertion slit 26.26 formed in the bottom surface 24b of the holding member 5. As a result, the target 2 can be easily removed from the holding member 5.

In this way, according to the configuration of this embodiment, while maintaining the cooling effect of the target 2, the target 2 can be easily attached and detached without employing a fastening method using screws or the like.

Note that the first to third inventions are not limited to the above embodiments, and various modifications can be made within the scope of the gist of each invention. Although the apparatus of the above embodiment has been described in which all of the first to third inventions are applied, it goes without saying that each of these inventions can be implemented independently.

When using a high melting point material as the target 2 attached to the holding member 5, it is preferable that this target has the structure shown in FIG.

That is, this target 2 is a sputtering material 4 with a high melting point.
1 and a backing plate material 42 made of, for example, aluminum, copper, etc., which has good thermal conductivity and good workability, are laminated in two layers and integrally formed. For joining the sputter material 41 and the backing plate material 42, for example, an undercut-shaped protrusion 41a is formed on the back side of the sputter material 41, and the protrusion 41a can be fitted into the packing plate material 42. An example is one in which a hole 42a is formed and the two are joined by fitting together. At this time, the backing plate material 42 is heated to a higher temperature than the temperature during sputtering, and the holes 42 are
a is expanded, the sputtering material 41 is fitted into the hole 42a in this state, and the two can be reliably bonded by subsequent thermal contraction. Note that bonding between the two may be performed using, for example, an indium layer or the like. By making the outer shape of the sputter material 41 and the backing plate material 42 similar to that of the above embodiment, the sputter material 41
1, efficient cooling can be carried out, and the work of attaching and detaching it is also extremely easy.

Next, to explain the third invention, in addition to the one in which the target 2 is arranged horizontally as in the above embodiment, there is another one in which the target 2 is placed vertically, which is called side sputtering. In this case, if the target 2 is only clamped at the center side, the perpendicularity may deteriorate due to the inclination of the target 2 or the like. If the target 2 is tilted, the positional relationship with the magnet will differ depending on the rotational position, making uniform sputtering impossible.

In order to reliably prevent this, it is preferable to provide a member for clamping between the end surface of the peripheral portion of the target 2 and the facing surface of the holding member 5, as shown in FIG. For this,
As shown in FIG. 6, four locking pins 23 are formed and fixed to the end surface of the peripheral edge of the target 2 at intervals of, for example, 90'' so as to protrude outward.

Then, in order to insert and lock this locking pin 23,
As shown in FIG.
An insertion slit 26 and a locking groove 27 are formed at the location.

In this way, by clamping the periphery of the target 2 at four locations, the target 2 can be clamped as shown in FIG.
Even when the magnet 10 is held vertically, it can maintain its verticality even if it expands due to heat, and the positional relationship with the magnet 10 can be maintained constant at each position during rotation. be able to. In particular, compared to the case where only the central portion of the target 2 is clamped, the effect of preventing the target from tilting is greater than when clamping the peripheral edge of the target 2, so that more uniform sputtering can be ensured.

Note that the above effect can be similarly achieved as long as the target 2 is clamped at three or more locations on the peripheral edge side.

Here, in the above embodiment, since the locking pin 24 is erected on the peripheral end face of the target 2, the wall thickness t1 of the peripheral edge of the target 2 is made thicker than the wall thickness t2 of the inner region (the (See Figure 5). Since the peripheral edge of the thick target 2 comes into close contact with the opposing surface of the holding member 5, a wider cooling surface can be ensured, which is also effective in improving cooling efficiency. Note that the reason why only the peripheral edge of the target 2 is made thicker as described above is because if the surface facing the moving magnet 10 is also made thicker, the magnetic field of the rotating magnet 10 must be made stronger. This is also because there is no need to increase the thickness of such a region. The configuration of increasing the thickness of the peripheral edge of the target 2 as described above is not necessarily applied to the third invention, but from the viewpoint of increasing the cooling effect, it is preferable to apply it to the second invention as well. .

More preferably, as shown by the broken line in FIG. 5, a notch 50 is provided in the center corner of the bottom surface of the large diameter hole 24 of the holding member 5 in a tapered shape, for example, over a predetermined area. Things are good. Then, when the target 2 thermally expands, the notch 50 acts as a relief part for the target 2, and the target 2 swells toward the side that comes into close contact with the holding member 5, so that deterioration of cooling efficiency can be prevented. I can do it.

Note that the electrode to which the present invention is applied is not limited to the target in the sputtering apparatus as in the above embodiment, but also various other electrodes that are coolably held by at least a holding member, such as a cathode target in an X-ray source, Target in an ion source.

It is also possible to apply the present invention to plasma etching electrodes, plasma equipment such as plasma CVD, and the like.

[Effects of the Invention] As explained above, according to the first invention, even if the adhesion between the electrode and the holding member is poor, by introducing gas between the electrodes and the holding member, it is possible to Heat exchange can be carried out efficiently. Further, according to the second invention, the thermal gradient from the center to the periphery of the electrode can be efficiently reduced by ensuring close contact between the peripheral edge of each stage formed on the electrode and the surface of the holding member opposing this through thermal expansion. It becomes possible to remove it. Furthermore, according to the third aspect of the invention, since the central part of the electrode where the temperature rises particularly significantly can be mechanically clamped with the holding member, the central part of the electrode can be prevented from warping.

Adhesion between the opposing surfaces of the holding member can be ensured, thereby ensuring the cooling effect of the electrodes. Furthermore, by performing this clamp on the back side of the central part of the electrode,
It becomes possible to ensure effective use of the surface side of the electrode.

As described above, the first to third inventions all make it possible to perform a more effective cooling effect on the electrode.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view showing an example of a sputtering apparatus to which the first to third inventions are applied, FIG. 2 is a schematic perspective view for explaining the structure of attachment of a target and a holding member, and FIG. 3 4 is a schematic explanatory diagram showing an example in which the target is integrated with a two-layer structure of a target material and a backing plate material, FIG. 4 is a schematic explanatory diagram for explaining a modification of the clamp member formed on the electrode, FIG. 5 is a schematic sectional view for explaining an embodiment in which the first to third inventions are applied to a cytosobatter device, and FIG. 6 is a back view of the target used in the device of FIG. , FIG. 7 is a schematic cross-sectional view of a holding member used in the apparatus of FIG. 5. 2... Electrode (target), 5... Holding member, 20... Gas introduction tube, 21...
Large diameter part, 21a... Peripheral part, 22... Small diameter part, 22
a...Peripheral portion, 23.26.27...Clamp member, 24...Large diameter hole, 25...Small diameter hole, 24a, 25
a...Inner peripheral surface, 50...Notch. Agent Patent attorney Inoue - (1 other person) Figure

Claims (5)

[Claims] (1) An electrode structure in which an electrode is coolably held by a holding member, characterized in that a gas is introduced between the electrode and the holding member. (2) In an electrode structure in which an electrode is coolably supported by a holding member, a stepped portion is formed on the back side of the electrode, and at least two areas, the peripheral edge of the electrode and the peripheral edge of the stepped portion, are held by thermal expansion. An electrode structure characterized by being brought into close contact with opposing surfaces of members. (3) An electrode structure in which an electrode is coolably held by a holding member, characterized in that a clamp member is provided for clamping the holding member on the back side of a central portion that is not exposed to the surface of the electrode. (4) The electrode structure according to claim 3, wherein clamp members are provided at at least three locations on the end face of the peripheral edge of the electrode for clamping between the opposing surface of the holding member. (5) The electrode structure according to any one of claims 2 to 4, wherein the peripheral edge of the electrode is thicker than the inner region.