JPH10259475A - Sputtering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the scattering of adhesives, an earth shield, the side face of a target or the like and to prevent the generation of defects in a thin coating by cooling a target fixed to an electrode by adhesives by a cooling mechanism capable of sufficiently cooling the position to form the vicinity of the outer peripheric part of the target in a target fixing member. SOLUTION: In a vacuum vessel, a target 2 is fixed to a backing plate fixed to a supporting stand 32 of an electrode by adhesives 23 made of indium series or the like, and the other electrode fixing a substrate is arranged oppositely thereto. While the target 2 is cooled via a channel 7A provided in the baking plate 31A, sputtering is executed, thin coating is formed on the substrate. The channel 7A is arranged at the side outer than the position in the vicinity of the outer peripheral part of the target or the position of the outer shape line thereof. Preferably, the amt. of cooling water to be fed to the channel 7A is controlled and the position in the vicinity of the outer peripheral part of the target of the backing plate 31A is cooled to a prescribed temp. in accordance with the m.p. of the adhesives 23.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sputtering apparatus in which an electrode for fixing a target with an adhesive and an electrode for fixing a substrate are opposed to each other in a vacuum vessel and provided with a cooling mechanism for cooling the target.

[0002]

2. Description of the Related Art Optical information recording media have attracted attention because of their high density and large capacity, and have been used in various applications. For example, a read-only optical disk includes a compact disk and a CD-ROM dedicated to data reproduction, and is widely used in the music field, computer field, game field, and the like. In addition, write-once optical discs that can be recorded only once are used in document filing systems, data filing systems, and the like, particularly in fields where data security is important.

Further, a rewritable optical disk capable of erasing and re-recording recorded information is expected to contribute to expanding the use of the optical disk because it is capable of restoring and updating data and can be used repeatedly by rewriting. Is done. As such rewritable optical disks, magneto-optical disks and phase-change optical disks have been put to practical use, and are used for data files and the like.

In the process of manufacturing such an optical disk, the work of forming a thin film such as a recording layer is usually performed by depositing a thin film forming material on a signal recording surface of a substrate by sputtering using a dedicated sputtering apparatus. Have been done.

As a conventional sputtering apparatus, for example, there is a magnetron sputtering apparatus using a flat target as shown in FIG. FIG. 5 is an enlarged view showing the vicinity of the target in FIG.

The apparatus comprises an electrode 3 for fixing a target 2 with an adhesive 23 in a housing 1 forming a vacuum vessel.
And an electrode 5 for fixing the substrate 4 are opposed to each other.
The backing plate 3 to which the target 3 is directly adhered by the adhesive 23 is used as the electrode 3 on the side where the target 2 is fixed.
1 and a support table 32 for supporting the same.
The outer edge of the backing plate 31 is
2 is attached with bolts 33. On the lower side of the backing plate 31, the cross section is separated by a predetermined distance and the N pole −S
A magnet member 6 having a structure of pole-N pole is arranged.

A water passage 7 is integrally formed below the backing plate 31 so as to protrude into a gap between the adjacent N pole and S pole of the magnet member 6. This waterway 7
Constitutes a water cooling mechanism for cooling the target, and has conventionally been provided along a position (erosion portion) 21 of the target 2 where sputtering is most intense.

Reference numeral 8 denotes a ring-shaped earth shield provided so as to prevent the electrode portions other than the target 2 from being sputtered, and is disposed at a predetermined distance from the target 2. Reference numeral 9 denotes an introduction pipe for introducing argon gas (Ar) into the housing 1, reference numeral 10 denotes an exhaust pump for evacuating the housing 1 to a vacuum, and reference numeral 11 denotes an exhaust pump via the support 32. This is a power supply for supplying electricity to the backing plate 31.

Therefore, the substrate 4 is fixed to the electrode 5, the target 2 is fixed to the backing plate 31 using an indium-based adhesive 23, and argon gas is injected into the housing 1 with the housing 1 evacuated. By introducing and energizing the backing plate 31, atoms in the target 2 are sputtered and adhere to the substrate 4. At this time, since the plasma generated by the action of the magnet is confined in the vicinity of the target 2, sputtering is efficiently performed.

Another example of a conventional magnetron sputtering apparatus is shown in FIG. This device cools the backing plate through a water channel that is not integral with the backing plate.

That is, as shown in FIG. 7, which is an enlarged view of the vicinity of the target of this apparatus, a cooling plate 35 is provided between a support 32 and a backing plate 34 to form a water passage 7 in the support 32. ing. This waterway 7
The cooling range of the target 2 is set inside the outline of the target 2.

[0012]

However, in such a conventional sputtering apparatus, in particular, when the film forming rate is high, indium in the adhesive layer is melted and scattered by heat generated at the time of sputtering. There is a problem that the indium adheres to the substrate to cause a defect.

The scattered indium causes an abnormal discharge (arcing) between the adhesive layer and the earth shield to increase the scatter of the indium. Further, a vicious cycle is caused in which the earth shield is melted and scattered, and the side surface of the target is melted and scattered, thereby increasing defects on the substrate.

In order to prevent this, Japanese Patent Application Laid-Open No. 7-292
No. 465 proposes to cover the outer periphery of the target so that the end face of the adhesive layer such as indium is not exposed, but the effect of this method is not sufficient.

If the film formation rate cannot be increased, the productivity is greatly reduced in the case of forming a thick layer, which is a serious problem. The present invention has been made in view of such problems of the prior art, and prevents the adhesive (indium or the like) fixing the target to the backing plate from being melted, causing the adhesive to be scattered or the earth shield to be scattered. It is an object of the present invention to provide a sputtering apparatus capable of preventing the generation of defects in a thin film due to scattering due to arcing and scattering on the side surface of a target.

[0016]

Means for Solving the Problems In order to solve the above problems, the present inventors have conducted intensive studies and as a result, the portion where the temperature rise of the backing plate is the largest is not the erosion portion but the mounting of the backing plate on the support base. Part (bolt attachment position). That is, this portion is a portion where the electric resistance is the largest in the circuit for applying power to the target, and is a central portion of heat generation. Furthermore, it has been found that the heat generated in this portion is transmitted to the adhesive (indium) layer through the backing plate, thereby causing the indium to melt and scatter.

Based on this finding, the invention according to claim 1 is directed to a sputtering method in which an electrode for fixing a target with an adhesive and an electrode for fixing a substrate are opposed to each other in a vacuum vessel and provided with a cooling mechanism for cooling the target. In the apparatus, the cooling mechanism is configured to sufficiently cool a position of the member to which the target is bonded, which is near the outer edge of the target, and provides the sputtering apparatus.

According to a second aspect of the present invention, an electrode for fixing a target with an adhesive and an electrode for fixing a substrate are disposed opposite to each other in a vacuum vessel, and a water cooling mechanism for cooling the target is provided. In a sputtering apparatus integrally formed with a backing plate to which a target is adhered, while arranging the water channel at a position near the target outer edge of the backing plate,
A sputtering apparatus provided with cooling water supply means for controlling the amount of cooling water supplied to the water channel to an amount capable of cooling the position of the backing plate to a predetermined temperature corresponding to the melting point of the adhesive for fixing the target. I will provide a.

According to a third aspect of the present invention, an electrode for fixing a target with an adhesive and an electrode for fixing a substrate are disposed opposite to each other in a vacuum vessel, and a water cooling mechanism for cooling the target is provided. In a sputtering apparatus formed separately from the backing plate to which the target is adhered, the water channel is arranged at a position outside the outline of the target, and the amount of cooling water supplied to the water channel is controlled by the backing plate. A cooling water supply means for controlling an outer edge of the cooling water to an amount capable of being cooled to a predetermined temperature corresponding to a melting point of an adhesive for fixing a target.

The predetermined temperature in claims 2 and 3 indicates a temperature at which the above-mentioned melting and scattering reduction does not occur in accordance with the melting point of the adhesive for fixing the target. When pure indium having a temperature of 0.6 ° C. is used as the adhesive for fixing the target, the temperature is set to 120 ° C. or lower, preferably 40 ° C. or lower.

[0021]

Embodiments of the present invention will be described below. (First Embodiment) Instead of the backing plate 31 of the sputtering apparatus shown in FIG. 4, a sputtering apparatus having the backing plate 31A shown in FIG. Produced.

The backing plate 31A is provided with a water passage 7A for circulating the cooling water, at a position L1 (near the outer edge of the target), which is an end face of the target 2 when the target 2 is bonded, that is, a mounting bolt to the support base 32. 33
It is located just inside the receiving position. This waterway 7A
Was supplied with water at 20 ° C. at a rate of 4 liters / minute.

A target 2 having a size of 200 mm.times.446 mm and a predetermined thickness is adhered to the backing plate 31A with an adhesive (pure indium) 23, and a polycarbonate substrate 4 having a groove having an outer diameter of 120 mm and a thickness of 1.2 mm. Was fixed to the electrode 5. And the housing 1
After the inside of the chamber was evacuated to a high vacuum of 1 × 10 ⁻⁴ Pa or less, Ar gas was introduced, and power having a magnitude corresponding to the type of the target 2 was supplied while the Ar gas concentration was 2 Pa.

On the substrate 4, first, a ZnS—SiO ₂ sintered plate is used as a target 2, and a high-frequency power of 5 kW is supplied, so that a ZnS—SiO 2
₂ Protective layer, then SbTeGe alloy plate to target 2
, And a SbTeGe recording layer having a thickness of 30 nm was laminated by supplying a DC power of 0.2 KW. Next, using a ZnS-SiO ₂ sintered plate as the target 2 and supplying high-frequency power of 3 KW,
A 50 nm thick Al alloy reflective layer was laminated by supplying a ZnS-SiO ₂ protective layer of 0 nm and an alloy plate containing Al as a main component as a target 2 and supplying a DC power of 2 KW.

Thereafter, the surface of the reflection layer was coated with an ultraviolet curable resin. In this way, the phase change optical disk
When the byte error rates in all the regions of the obtained phase change optical disks were measured, the error rates of all the disks were less than 2 × 10 ⁻⁵ . In addition, no indium was detected in the thin film even when the defective portion of the disk was analyzed. The temperature of the portion where the backing plate 31A was attached to the support 32 was 40 ° C. or less.

On the other hand, an error rate of a phase change optical disk manufactured under exactly the same conditions as described above except that the sputtering apparatus shown in FIG. 4 to which the backing plate 31 of FIG. 5 is attached is used has an error rate of 5 × 10 ^{−. The} yield was low because there were twelve sheets that were ⁵ or more. Then, when a defect of the disk having a low error rate was analyzed, indium was detected in the thin film. The temperature of the portion where the backing plate 31 was attached to the support 32 was 125 ° C. (2nd Embodiment) Backing plate 31B shown in FIG.
A phase-change optical disc was manufactured in the same manner as in the first embodiment except that the above was used.

That is, the backing plate 31B
In addition to the water channel 7 for cooling the erosion portion as shown in FIG. 5, the water channel 7A has the same water channel 7A as the first embodiment (a water channel disposed just inside the position for receiving the mounting bolt 33).

Thus, the phase-change optical disk 100
When the byte error rates in all the regions of the obtained phase change optical disks were measured, the error rates of all the disks were less than 2 × 10 ⁻⁵ . In addition, no indium was detected in the thin film even when the defective portion of the disk was analyzed.

Further, when the temperature of the cooling water during the formation of the first layer ZnS—SiO ₂ was measured,
In the channel 7, the cooling water supplied at 20 ° C. returned to 21 ° C., but in the channel 7A, the cooling water supplied at 20 ° C. returned to 38 ° C. From this result, the temperature rise of the backing plate 31B is more likely to occur at the outer edge 2 than at the position below the erosion portion 21 of the target 2.
It can be seen that the position below 2 is larger. (Third Embodiment) Instead of the backing plate 34, the cooling plate 35, and the water channel 71 of the sputtering apparatus shown in FIG. 6, the backing plate 34 shown in FIG.
A, except that a sputtering apparatus equipped with a cooling plate 35A and a water passage 71A was used.
A phase change optical disk was manufactured by performing sputtering in the same manner as in the embodiment.

That is, the thickness of the backing plate 34A is made smaller than before, the area of the cooling plate 35A is made larger than that of the backing plate 34A, and the thickness of the cooling plate 35A on which the backing plate 34A is placed is made thinner. Further, the cooling range of the target 2 by the water channel 71A for circulating the cooling water is
The target 2 was set outside the outline position L1.

The cooling plate 35A is placed in a vacuum, and the cooling plate 35A is fixed to the support base 32A by the O-ring 36 and the bolt 37. The cooling plate 35A has a vertical portion (a portion extending in the vertical direction) 7 of the water passage 71A.
1B is disposed between the bolt 37 and the backing plate 34A in a plan view.

In this way, the phase-change optical disk 100
When the byte error rates in all the regions of the obtained phase change optical disks were measured, the error rates of all the disks were less than 2 × 10 ⁻⁵ . In addition, no indium was detected in the thin film even when the defective portion of the disk was analyzed.

On the other hand, a phase-change optical disk manufactured under exactly the same conditions as described above except that the sputtering apparatus of FIG. 6 provided with the backing plate 34, the cooling plate 35, and the water channel 71 of FIG. There were 10 sheets with an error rate of 5 × 10 ⁻⁵ or more, and the yield was low. Then, when a defect of the disk having a low error rate was analyzed, indium was detected in the thin film.

[0034]

As described above, according to the sputtering apparatus of the present invention, the melting of the adhesive (indium or the like) fixing the target to the backing plate is prevented, and the scattering of the adhesive and the arcing of the earth shield are prevented. And the generation of defects in the thin film due to scattering of the target side surface. As a result, the quality of the thin film can be maintained even if the deposition rate is increased,
The productivity when the film thickness is large can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing the vicinity of a target (including a water channel) of a sputtering apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic sectional view showing the vicinity of a target (including a water channel) of a sputtering apparatus according to an embodiment of the present invention.

FIG. 3 is a schematic sectional view showing the vicinity of a target (including a water channel) of a sputtering apparatus according to an embodiment of the present invention.

FIG. 4 is a schematic configuration diagram illustrating an example of a conventional sputtering apparatus.

FIG. 5 is a schematic sectional view showing an arrangement of a water channel in a backing plate conventionally installed in the sputtering apparatus of FIG.

FIG. 6 is a schematic configuration diagram illustrating an example of a conventional sputtering apparatus.

FIG. 7 is a schematic sectional view showing the arrangement of a backing plate, a cooling plate, and a water channel conventionally installed in the sputtering apparatus of FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 housing 2 target 3 target-side electrode 4 substrate 5 substrate-side electrode 6 magnet member 7 water path 7A water path 8 earth shield 9 Ar gas introduction pipe 10 exhaust pump 11 power supply 21 erosion section 22 target outer edge 23 adhesive 31 backing plate Reference Signs List 31A backing plate 31B backing plate 32 support stand 33 backing plate mounting bolt 35 cooling plate 35A cooling plate 37 cooling plate mounting bolt 36 O-ring 71 water channel 71A water channel 71B vertical portion of water channel L1 target end face position L2 target outline Line position

Claims (3)

[Claims] An electrode for fixing a target with an adhesive and an electrode for fixing a substrate are opposed to each other in a vacuum vessel and provided with a cooling mechanism for cooling the target. A sputtering apparatus characterized in that the position of the member to be formed near the outer edge of the target is sufficiently cooled. 2. An electrode for fixing a target with an adhesive and an electrode for fixing a substrate are disposed in a vacuum vessel so as to face each other, and a water cooling mechanism for cooling the target is provided. In the sputtering apparatus formed integrally with the backing plate, the water channel is arranged at a position near the outer peripheral portion of the target of the backing plate, and the amount of cooling water supplied to the water channel is set at the position of the backing plate for fixing the target. A cooling water supply means for controlling an amount of cooling to a predetermined temperature according to a melting point of the adhesive. 3. An electrode for fixing a target with an adhesive and an electrode for fixing a substrate are disposed in a vacuum vessel so as to face each other, and a water cooling mechanism for cooling the target is provided. In the sputtering apparatus formed separately from the backing plate, the water channel is arranged at a position outside the outline of the target, the amount of cooling water supplied to the water channel, and the outer edge of the backing plate is fixed to the target. A cooling water supply means for controlling an amount of cooling to a predetermined temperature corresponding to a melting point of the adhesive for use.