JP2000256839A - Target and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a target capable of securing an excellent grade of joining between a target member and a backing plate, and its manufacturing method. SOLUTION: A high temperature brazing filler metal 2 is disposed on the surface, to be opposed to a backing plate 4, of a target member 1 and the high temperature brazing filler metal is solidified, and then, a low temperature brazing filler metal 3 having a melting point lower than that of the high temperature brazing filler metal is disposed on the high temperature brazing filler metal at a temperature where the high temperature brazing filler metal does not completely become molten. On the other hand, a low temperature brazing filler metal having a melting point lower than that of the high temperature brazing filler metal is disposed on the surface, to be opposed to the target member, of the backing plate. Subsequently, the target member and the backing plate are joined. By this method, the target, having a new structure in which the target member and the backing plate are joined via the brazing filler metals and the high temperature brazing filler metal and the low temperature brazing filler metal having a melting point than that of the high temperature brazing filler metal are disposed in the order from the target member side, can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a target which can be used for a sputtering method and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, a sputtering method has been known as one technique for forming a thin film. The sputtering method is a method in which fine particles are beaten out from the surface of a target member that supplies all or some of the elements of the thin film by the impact of argon or the like, and the fine particles are attached to an opposing substrate to form a thin film. The target member used in this sputtering method is heated during the sputtering period because it receives the above-described impact of argon or the like.

[0003] Excessive heating of the target member may cause problems such as a change in sputtering characteristics and deformation of the target member. Therefore, the target member is usually cooled during the sputtering period. At this time, there is a method of directly cooling the target member. However, usually, the target member is often used by transferring the heat of the target member to the outside and joining a backing plate serving as a member for supporting the target member.

[0004] The joining between the target member and the backing plate is usually performed by brazing using a brazing material such as In brazing. And (4A, 5A, 6A, 7A, 8A) in the periodicity table especially represented by Cr
In some cases, a target member mainly composed of any element selected from the group is poor in wettability with a brazing material, and is often difficult to braze as it is. Therefore, as described in JP-A-62-222060 or JP-B-6-77805, a method of improving the wettability by forming a coating layer by plating or the like on the joining surface of the target member in advance is adopted. Have been.

[0005]

The above-described method of forming a coating layer on a target member is extremely advantageous in improving brazing properties. On the other hand, the formation of a coating layer by plating or the like has a problem that the production cost is greatly increased. Further, when a plurality of coating layers are formed, the cost is further increased. An object of the present invention is to provide a target and a method for manufacturing the same, which can ensure good bonding quality even with only a brazing material.

[0006]

Means for Solving the Problems The present inventor studied a method of joining a target member having poor wettability with a brazing material using only a brazing material, and arranged a high-temperature brazing material on the target member side.
Furthermore, it has been found that the problem of wettability between the target member and the brazing material can be solved by arranging a brazing material having a lower melting point than the high-temperature brazing material on the high-temperature brazing material.

That is, according to the manufacturing method of the present invention, after a high-temperature brazing material is arranged on a surface of a target member facing a backing plate, the high-temperature brazing is solidified, and then the high-temperature brazing is performed at a temperature at which the high-temperature brazing is not completely melted. A low-temperature brazing material having a lower melting point than the high-temperature brazing material is disposed on the surface of the backing plate facing the target member. Then, the target member and the backing plate are joined.

According to the manufacturing method of the present invention, a target is formed by joining a target member and a backing plate via a brazing material, and a high-temperature brazing material, and a low-temperature brazing material having a lower melting point than the high-temperature brazing material are provided from the target member side. A target of the present invention having a novel structure arranged in the order of the brazing material can be obtained.

[0009] Another manufacturing method of the present invention is a method for manufacturing a semiconductor device, comprising the steps of:
After placing the high temperature brazing material, the high temperature brazing is solidified,
After placing the high-temperature brazing material on the side of the backing plate facing the target member, the high-temperature brazing is solidified, and then the target member and the backing plate have a melting point higher than that of the high-temperature brazing at a temperature at which the respective high-temperature brazing is not completely melted. Low and low temperature brazing are arranged on the high temperature brazing, respectively, and then the target member and the backing plate are joined.

According to the above-described manufacturing method, a target in which a target member and a backing plate are joined via a brazing material, wherein a high-temperature brazing material and a low-temperature brazing material having a lower melting point than the high-temperature brazing material are provided from the target member side. A new target of the present invention can be obtained in which a material, a high-temperature brazing material, and a backing plate are arranged in this order.

[0011]

As described above, an important feature of the present invention is that a high-temperature brazing material, a brazing material having a lower melting point than the high-temperature brazing material are used, and a high-temperature brazing material is arranged on the target member side. It is in. The present inventor has studied to omit the step of forming a coating such as plating, and has studied in detail the wettability between the brazing material and the target member. Then, even though brazing at the test piece level was possible, a phenomenon was encountered that brazing could not be performed with a target member that actually secured a wide bonding surface of 0.01 m ² or more.

As a result of further study, it has been found that, in the case of a target member having poor wettability, in the molten state in which the brazing material is disposed on the surface, the flow of the brazing material is extremely easy during joining with the backing plate or during handling. It was found that an immobile body film was immediately formed on the surface where the brazing material was no longer present, leading to poor brazing.

As a result of various trials, the present inventor has:
First, by arranging a high-temperature brazing material on the target member side and solidifying, a brazing material that does not flow is secured on the surface to be joined of the target member, and further joined to the backing plate with a low-temperature brazing material, It has been found that joining quality can be ensured by joining a high-temperature solder and a low-temperature solder. Specifically, FIG. 1 shows an example of the configuration of the target of the present invention. That is, the high-temperature brazing material 2, the low-temperature brazing material 3, and the backing plate 4 are arranged in this order from the target member 1 side.

In the present invention, the low-temperature brazing is performed at a temperature at which the high-temperature brazing is not completely melted. If the high-temperature brazing is completely melted, the flow of the high-temperature brazing material is liable to occur. This is because it may be. Further, in the present invention, the low-temperature brazing material having a lower melting point than the high-temperature brazing material is disposed on the surface of the backing plate facing the target member, without disposing the brazing material on the backing plate side. This is because if only the low-temperature brazing on the side is used, the bonding tends to be defective.

The present invention provides a method capable of improving the poor wettability of the target member side, and it is possible to directly contact the high-temperature brazing to the target member having poor wettability to join the target member. Even those coated with plating or the like may be applied for the purpose of improving poor bonding caused by wettability. Further, when the backing plate is made of stainless steel having poor wettability, the backing plate side can be used in combination with the high-temperature brazing material and the low-temperature brazing similarly to the target member side.

In this case, for example, the high-temperature brazing material can be arranged by arranging the high-temperature brazing material on the surface of the target member facing the backing plate and then solidifying the high-temperature brazing material. On the other hand, on the backing plate,
After arranging the high-temperature brazing material on the surface facing the target member, the high-temperature brazing is solidified, so that the high-temperature brazing material can also be arranged on the backing plate side.

Then, a low-temperature wax having a melting point lower than that of the high-temperature wax at a temperature at which the high-temperature wax of each of the target member and the backing plate does not completely melt is disposed on the high-temperature wax, respectively. If the target member and the backing plate are both made of a material having poor wettability, high bonding strength can be obtained without plating. Thereby, as shown in FIG.
From the side, a target is arranged in the order of the high-temperature brazing material 2, the low-temperature brazing material 3 having a lower melting point than the high-temperature brazing material, the high-temperature brazing material 2, and the backing plate 4.

In the present invention, a flux generally used for brazing can be used. The flux removes an oxide film on a surface to be joined and improves wettability. The flux can be selected according to the applied temperature at the time of brazing the high-temperature brazing material and the low-temperature brazing material. High and low temperature waxes are
Although the target member side and the backing plate side may be different, the use of various kinds of brazing materials increases the cost, so that the same brazing materials are preferably used. In the present invention, the target member is preferably applied to a target member mainly containing any element selected from the group of (4A, 5A, 6A, 7A, 8A) in the periodic table. This is because if the target is a metal having good wettability such as Cu, it is not necessary to compensate for the poor wettability according to the present invention.

[0019]

Embodiments of the present invention will be described below. 170φ ×
A target member having a composition shown in Table 1 machined to 6.35 t (mm), a backing plate machined to 203 φ × 20 t (mm), a high-temperature brazing and a low-temperature brazing were prepared.

[0020]

[Table 1]

In the combinations shown in Table 2, a high-temperature brazing flux was applied to the brazing surface of the target member, a high-temperature brazing material was placed, and the brazing surface was heated with a heater. Then, after heating with a heater, the high-temperature brazing was melted and adapted to the target member to form a high-temperature brazing film, and then cooled and washed with hot water. The Cu backing plate was used without using a high-temperature brazing. In the case of a stainless steel backing plate, there is concern about deterioration of wettability. Therefore, similarly to the above-described target, a high-temperature brazing flux was applied, a high-temperature brazing material was placed, and the brazing surface was heated with a heater. Then, after heating by a heater, the high-temperature wax was melted and adapted to a backing plate to form a high-temperature wax film, and then cooled and washed with hot water.

When the high-temperature brazing is arranged on the target member or the backing plate, the brazing temperature according to the type of brazing material shown in Table 1 is applied. Next, a flux for low-temperature brazing was applied with the brazing surface of the backing plate and the brazing surface of the target member facing upward, and a low-temperature brazing was placed on the flux, and the heater was heated simultaneously. As the heating temperature of the low-temperature brazing, a brazing temperature according to the type of the brazing material shown in Table 1 was applied.

When the low-temperature brazing material has melted, the two brazing materials are adapted to each other, the target member is turned over, the superposed position is set on the backing plate, and a weight of 20 kg is placed on the target member from above and pressurized. And cooled. Table 2 shows the results of the measurement of the area ratio of the brazed joints of the obtained targets by the ultrasonic flaw detection method. As shown in Table 2, it was confirmed that all of the targets of the present invention had a bonding rate of 95% or more.

Further, a test piece was cut out from the obtained target and the bonding strength was measured by a tensile test. The results are shown in Table 2. As shown in Table 2, the target of the present invention has a sufficient bonding strength. Was confirmed. In addition, although joining was also attempted using only low-temperature brazing without using high-temperature brazing, any of the targets could only obtain a bonding strength enough to separate the backing plate by its own weight.

[0025]

[Table 2]

[0026]

According to the present invention, the equipment for plating and environmental problems required for the brazing of the material of the target member and the backing plate having low wettability to the low-temperature brazing, cost and processing time by the ion plating facility are provided. It is a technology that is indispensable for the practical use of the target brazing as the size of the target used for the sputtering method is increased and the quality can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an example of a bonding configuration of a target according to the present invention.

FIG. 2 is a diagram showing another example of the joining configuration of the target of the present invention.

[Explanation of symbols]

1. 1. target member; 2. high temperature brazing material; 3. low-temperature brazing material; Backing plate

Claims (4)

[Claims] 1. A target in which a target member and a backing plate are joined via a brazing material,
A target, wherein a high-temperature brazing material and a low-temperature brazing material having a lower melting point than the high-temperature brazing material are arranged in this order from the target member side. 2. A target in which a target member and a backing plate are joined via a brazing material,
A target, comprising: a high-temperature brazing material, a low-temperature brazing material having a lower melting point than the high-temperature brazing material, a high-temperature brazing material, and a backing plate in this order from the target member side. 3. A high-temperature brazing material is placed on the surface of the target member facing the backing plate, and then the high-temperature brazing is solidified. Then, at a temperature at which the high-temperature brazing is not completely melted, the melting point is lower than that of the high-temperature brazing. A low-temperature brazing material is disposed on the high-temperature brazing material, and a low-temperature brazing material having a lower melting point than the high-temperature brazing material is disposed on a surface of the backing plate facing the target member. A method for manufacturing a target, comprising joining a member and the backing plate. 4. A high-temperature brazing material is arranged on the surface of the target member facing the backing plate, and then the high-temperature brazing is solidified, while the high-temperature brazing material is arranged on the surface of the backing plate facing the target member. Thereafter, the high-temperature wax is solidified, and then a low-temperature wax having a lower melting point than the high-temperature wax at a temperature at which the high-temperature wax of each of the target member and the backing plate is not completely melted is placed on the high-temperature wax, and then the A method for manufacturing a target, comprising joining a target member and the backing plate.