Diffusion-bonded sputter target assembly and method of manufacturing

Abstract

A method of making a diffusion bonded sputter target assembly is provided. A target blank comprising a first metal or alloy has a first surface defining a sputtering surface and a second surface. A second metal or alloy is placed around the target blank. A backing plate is provided adjacent the second metal or alloy that is positioned alongside of the second target surface. This assembly is then diffusion bonded, and a portion of the second metal overlying the sputtering surface of the target is removed to expose the target sputtering surface. W target or W alloy target/Ti or Ti alloy backing plate assemblies are provided with an Al interlayer positioned intermediate the W or W alloy target and backing plate. The assembly has a bond strength exceeding 50 MPa.

1 . A diffusion bonded target/backing plate assembly wherein said target is composed of a target material consisting of W or W alloy, said assembly further comprising an interlayer positioned intermediate said W target and said backing plate, said backing plate comprising Ti or Ti alloy and said interlayer comprising Al or Al alloy, said assembly having a bond strength exceeding 50 MPa, wherein said assembly comprises a sidewall portion having exposed Al or Al alloy and exposed Ti or Ti alloy surfaces, said assembly having a plasma coating overlying said sidewall, wherein said plasma coating consists of said target material. 
     
     
         2 . A diffusion bonded W target/backing plate assembly as recited in  claim 1  wherein said bond strength exceeds 68.94 MPa (10 ksi). 
     
     
         3 . A diffusion bonded W target/backing plate assembly as recited in  claim 1  wherein said W target has a density in excess of 99.7%, a grain size of less than 100 microns, oxygen content of less than 100 ppm, carbon content of less than 30 ppm, and W metallic purity of 99.999% and greater. 
     
     
         4 . A diffusion bonded W target/backing plate assembly as recited in  claim 1  wherein said plasma coating has a thickness of about 0.001-0.020 inches. 
     
     
         5 . A diffusion bonded W target/backing plate assembly as recited in  claim 1  wherein said interlayer is Al 6061 and said bond strength exceeds 60 MPa.