Low-energy method for fabrication of large-area sputtering targets

1. A method of forming a large-area sputtering target, the method comprising:

providing a plurality of sputtering targets each comprising a backing plate and a refractory metal layer disposed thereon; and

spray depositing a refractory metal powder on an interface between the sputtering targets, the refractory metal powder consisting essentially of the same metal as each refractory metal layer, thereby joining the refractory metal layers of the sputtering targets and forming the large-area sputtering target.

2. The method of claim 1 , wherein each backing plate comprises copper, aluminum, or an alloy of beryllium with at least one of copper or aluminum.

3. The method of claim 1 , wherein the refractory metal powder comprises at least one of niobium, tantalum, tungsten, molybdenum, zirconium, or titanium.

4. The method of claim 1 , wherein the refractory metal powder is deposited by cold spraying.

5. The method of claim 1 , wherein, during the spray depositing of the refractory metal powder, neither the refractory metal powder nor any portion of any backing plate melts.

6. The method of claim 1 , wherein an oxygen content of the refractory metal powder prior to spray depositing is substantially equal to an oxygen content of the refractory metal powder after spray depositing.

7. The method of claim 1 , further comprising inserting the large-area sputtering target into a sputtering tool without removing any backing plate.

8. The method of claim 1 , wherein, after spray deposition, the refractory metal powder is substantially free of preferred crystalline texture.

9. The method of claim 1 , wherein, after spray deposition, the refractory metal powder has an oxygen content less than 100 ppm.