Copper alloy sputtering target and method for manufacturing same
Provided is a copper alloy sputtering target, wherein, based on charged particle activation analysis, the copper alloy sputtering target has an oxygen content of 0.6 wtppm or less, or an oxygen content of 2 wtppm or less and a carbon content of 0.6 wtppm or less. Additionally provided is a method for manufacturing a copper alloy sputtering target, wherein a copper raw material is melted in a vacuum or an inert gas atmosphere, a reducing gas is thereafter introduced into the melting atmosphere, an alloy element is subsequently added to a molten metal for alloying, and an obtained ingot is processed into a target shape. The present invention aims to provide a copper alloy sputtering target that generates few particles during sputtering, and a method for manufacturing such a sputtering target.
1. A method for manufacturing a copper alloy sputtering target, wherein a copper raw material is melted in a water-cooled copper crucible or hearth under a vacuum or an inert gas atmosphere to obtain a molten copper, a reducing gas is thereafter introduced directly into the melting atmosphere to reduce oxygen content of the molten copper, thereafter the molten copper is translocated into another water-cooled copper crucible or hearth and an alloying element is subsequently added to the molten copper to obtain a molten copper alloy, and the molten copper alloy is cast to form a copper alloy ingot, which is then processed into a target shape to produce the copper alloy sputtering target having a purity of 99.999 wt % (5N) or higher and a total content of metal impurities of 1 wtppm or less and containing, as the alloying element, 0.1-15 at % of Al or 0.1-30 at % of Mn or both.
2. The method for manufacturing a copper alloy sputtering target according to claim 1 , wherein the reducing gas is hydrogen gas or carbon monoxide gas.
3. The method for manufacturing a copper alloy sputtering target according to claim 2 , wherein the melting of the copper raw material and the adding of the alloying element to the molten copper is performed using plasma arc melting, electron beam melting, or induction melting.
4. The method for manufacturing a copper alloy sputtering target according to claim 3 , wherein the water-cooled copper crucible or hearth for melting the copper raw material is different from the water-cooled copper crucible or hearth in which the alloying element is added to the molten copper.
5. The method for manufacturing a copper alloy sputtering target according to claim 4 , wherein the melting of the copper raw material and the adding of the alloying element to the molten copper are performed using plasma arc melting, and the processing of the copper alloy ingot includes steps of forging, rolling, and heat treatment to prepare a sputtering target material, which is machine-processed to form the target shape.
6. The method for manufacturing a copper alloy sputtering target according to claim 1 , wherein the melting of the copper raw material and the adding of the alloying element to the molten copper is performed using plasma arc melting, electron beam melting, or induction melting.
7. The method for manufacturing a copper alloy sputtering target according to claim 1 , wherein the water-cooled copper crucible or hearth for melting the copper raw material is different from the water-cooled copper crucible or hearth in which the alloying element is added to the molten copper.
8. The method for manufacturing a copper alloy sputtering target according to claim 1 , wherein the melting of the copper raw material and the adding of the alloying element to the molten copper are performed using plasma arc melting and the processing of the copper alloy ingot includes steps of forging, rolling, and heat treatment to prepare a sputtering target material, which is machine-processed to form the target shape.