Study on the microstructures, electrical resistance and mechanical properties of sputtering chromium target by HP, HIP and canning-HIP processes

摘要

In recent years, pure chromium (Cr) targets have been commonly used in metal surface coating treatment and flat-panel displays. In the traditional production of a pure Cr-target, there is a greater use of casting methods; however, the metal ingot frequently suffers from ingredient segregation, porosity and nonuniform microstructure defects. Powder metallurgy (PM) is a good method for fabricating high melting materials with better microstructure and properties. This study produced Cr targets using hot pressing (HP), hot isostatic pressing (HIP) and canning-HIP of PM technology. The experimental results showed that the Cr targets made by HP-HIP can further improve the density and mechanical properties. The relative density increases from 98.8% to 99.3%. Canning-HIP of the Cr target in particular, can provide smaller grain size (50 μm), lower porosity about 0.3%, and increased relative density to 99.7%, with a TRS of up to 58 MPa. The canning-HIP process also shows the optimal electrical resistivity (8.003 x 10~5 Ω-cm), which suits for applications in the sputtering process.