CROSS REFERENCE TO RELATED APPLICATIONS

This application claims benefit of priority to Japanese Patent Application 2018-219946 filed Nov. 26, 2018, the entire content of which is incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a sputtering target packaging structure and a method of packaging a sputtering target.

BACKGROUND

A sputtering method is known as a method of forming an inorganic thin film. Regarding a sputtering target, sputtering apparatuses performing the sputtering method include an apparatus using a flat-plate sputtering target and an apparatus using a cylindrical sputtering target.

Between them, the sputtering apparatus using a cylindrical sputtering target is configured to cool a target material from inside the cylindrical sputtering target and perform sputtering while rotating the cylindrical sputtering target. Therefore, in the sputtering apparatus using a cylindrical sputtering target, a usage efficiency of the target material is 70% or more. This use efficiency is very high as compared to the sputtering apparatus using a flat-plate sputtering target and is useful from the viewpoint of saving resources and reducing the economic burden.

On the other hand, when the sputtering targets are shipped or stored, both the cylindrical sputtering target and the flat-plate sputtering target are usually put in resin bags, and subsequently, the inside thereof is vacuum-sucked, or an inert gas is introduced therein. This is performed for preventing adhesion of dust or deterioration (e.g., oxidation) of the sputtering target. In a sputtering target packing apparatus described in WO2005/037649, at the time of vacuum suction of a hollow cathode type sputtering target having, for example, a U-shaped cross section covered with a resin bag, a space part of the sputtering target is vacuum-degassed through a through-hole disposed in a lid covering the space part of the sputtering target so that even a packing resin does not touch the space part of the sputtering target.

SUMMARY

Problem to be Solved by the Disclosure

From the viewpoint of saving resources and reducing the economic burden as described above, use of a cylindrical sputtering target is increasingly attracting attention. Particularly, considering stable installation in a sputtering apparatus, recently widely used cylindrical sputtering targets have a flange part disposed around an opening part at one end and an opening part at the other end sealed with a cap etc.

However, the present inventors found that a cylindrical sputtering target including such a flange part and a cap may cause many problems during vacuum suction and packaging for shipping or storage. First, since the cylindrical sputtering target is generally elongated and has a large inner volume, one end sealed with a cap causes a problem of difficulty in bringing the inside of the sputtering target into a sufficiently vacuum state at the time of packing. Second, if the cylindrical sputtering target has a flange part, a packing material is caught on an edge portion of the flange part even when vacuuming is directly performed, causing a problem that air inside and outside the sputtering target cannot successfully be evacuated.

FIG. 4is a schematic diagram showing a cross section of a cylindrical sputtering target brought into a vacuum-packed state by using a general method. As shown inFIG. 4, a cylindrical sputtering target10has a space12inside a cylinder part11with a flange part13disposed on an opening part at one end of the cylinder part11and a cap14disposed on an opening part at the other end of the cylinder part11. After covering the cylindrical sputtering target10with the packing material20for packing, vacuuming is performed from a (or b) inFIG. 4, i.e., a position at which vacuuming is usually performed. However, as described above, since the cylindrical sputtering target10is generally elongated and has a large inner volume of the space12inside the cylinder part11, and the packing material20is caught on a portion around the flange part13, the air in the space12inside the cylinder part11is not successfully evacuated. Ina state of packing by such a method, since the air remaining in the space12inside the cylinder part11gradually diffuses to the outside, and vacuum packing by the packing material20gradually loosens, the loosened packing material20and the cylindrical sputtering target10rub each other during transportation, so that the cylindrical sputtering target10may be scratched, or a surface of the cylindrical sputtering target10may be deteriorated (e.g., oxidized) by the air and moisture not completely evacuated.

An object of the present disclosure is to provide a packaging structure of a sputtering target and a method of packaging a sputtering target, capable of packaging a cylindrical sputtering target having a flange part at one end and the other end sealed in a sufficiently vacuum state on the outside and inside.

Solutions to the Problems

An embodiment of the present disclosure provides a sputtering target packaging structure comprising:

a sputtering target including a cylinder part, a flange part disposed on an opening part at one end of the cylinder part, and a cap disposed on an opening part at the other end of the cylinder part; and

a packing material made up of a sheet and covering an inner surface and an outer surface of the sputtering target in a close contact state, wherein

the packing material includes seal parts on both end sides of the sputtering target.

In an embodiment of the present disclosure, the seal parts may be located outside both ends of the sputtering target.

In an embodiment of the present disclosure, a vacuum state may be achieved between the packing material and the sputtering target.

In an embodiment of the present disclosure, a gap between the flange part of the sputtering target and the packing material of the packaging structure may be less than 10 mm after one week under atmospheric pressure at 20° C. from the time of packaging.

An embodiment of the present disclosure provides a sputtering target packaging structure comprising:

a sputtering target including a cylinder part, a flange part disposed on an opening part at one end of the cylinder part, and a cap disposed on an opening part at the other end of the cylinder part; and

a packing material made up of a sheet, wherein

a vacuum state is achieved between the sputtering target and the packing material and/or the sputtering target and the packing material are in a close contact state, and wherein

a gap between the flange part of the sputtering target and the packing material is less than 10 mm after one week under atmospheric pressure at 20° C. from the time of packaging.

In an embodiment of the present disclosure, the packing material may have a characteristic of hardly allowing permeation of oxygen and water.

In an embodiment of the present disclosure, the sputtering target may have a length of 1000 mm or more and 5000 mm or less in a longitudinal direction.

An embodiment of the present disclosure provides a method of packaging a sputtering target including a cylinder part, a flange part disposed on an opening part at one end of the cylinder part, and a cap disposed on an opening part at the other end of the cylinder part with a packing material, comprising the steps of:

covering an outside of the sputtering target with the packing material made up of a tubular sheet including opening parts at one end and the other end such that the flange part side of the sputtering target faces toward the one end of the packing material;

closing the opening part at one end of the packing material;

pushing into the inside of the sputtering target the one end of the packing material having the opening part closed on the flange part side of the sputtering target;

performing vacuuming from the opening part at the other end of the packing material on the cap side of the sputtering target and closing the opening part at the other end; and

opening a portion of the packing material on the flange part side of the sputtering target, performing vacuuming from an opening part in the portion, and closing the opening part in the portion.

An embodiment of the present disclosure provides a method of packaging a sputtering target including a cylinder part, a flange part disposed on an opening part at one end of the cylinder part, and a cap disposed on an opening part at the other end of the cylinder part with a packing material, comprising the steps of:

covering an outside of the sputtering target with the packing material made up of a bag-shaped sheet including a closing part at one end and an opening part at the other end such that the flange part side of the sputtering target faces toward the closing part of the packing material;

pushing into the inside of the sputtering target the one end of the closing part of the packing material on the flange part side of the sputtering target;

performing vacuuming from the opening part at the other end of the packing material on the cap side of the sputtering target and closing the opening part at the other end; and

opening a portion of the packing material on the flange part side of the sputtering target, performing vacuuming from an opening part in the portion, and closing the opening part in the portion.

In an embodiment of the present disclosure, the step of pushing the packing material into the inside of the sputtering target may include pushing the packing material into the inside of the sputtering target while inserting a core into the inside of the sputtering target.

In an embodiment of the present disclosure, at least one of the vacuuming from the opening part at the other end and the vacuuming from the opening part in the portion may be performed with the core inserted inside the sputtering target, and the method may include extracting the core after the vacuuming.

An embodiment of the present disclosure provides a method of packaging a sputtering target including a cylinder part, a flange part disposed on an opening part at one end of the cylinder part, and a cap disposed on an opening part at the other end of the cylinder part with a packing material, comprising the steps of:

covering an outside of the sputtering target with the packing material made up of a bag-shaped sheet including an opening part at one end and a closing part at the other end such that the flange part side of the sputtering target faces toward the opening part of the packing material;

closing the opening part at one end of the packing material;

opening a portion of the closing part of the packing material on the cap side of the sputtering target;

opening a portion of the packing material on the flange part side of the sputtering target;

pushing into the inside of the sputtering target the one end of the packing material having the opening part closed on the flange part side of the sputtering target;

performing vacuuming from the opening part in the portion on the cap side and closing the opening part in the portion on the cap side; and

performing vacuuming from the opening part in the portion on the flange part side and closing the opening part in the portion on the flange part side.

In an embodiment of the present disclosure, the step of pushing the packing material into the inside of the sputtering target may include pushing the packing material into the inside of the sputtering target while inserting a core into the inside of the sputtering target.

In an embodiment of the present disclosure, at least one of the vacuuming from the opening part in the portion on the cap side and the vacuuming from the opening part in the portion on the flange part side may be performed with the core inserted inside the sputtering target, and wherein the method may include extracting the core after the vacuuming.

In an embodiment of the present disclosure, the packing material may have a characteristic of hardly allowing permeation of oxygen and water.

In an embodiment of the present disclosure, the length of the packing material in the longitudinal direction may be twice or more the length of the sputtering target in the longitudinal direction.

In an embodiment of the present disclosure, the method may comprise sealing the packing material along the longitudinal direction of the packing material so as to reduce the inner diameter of the packing material after covering the outside of the sputtering target with the packing material.

Effect of the Disclosure

The packaging structure of a sputtering target and the method of packaging a sputtering target according to the present disclosure enable packaging of the cylindrical sputtering target having the flange part at one end and the other end sealed in a sufficiently vacuum state on the outside and inside.

