Chemical-mechanical polishing of bulk tungsten substrate

Bulk tungsten is very promising for packaging and micro-devices for its high strength, radiation resistance, high melting point and conductivity. In this paper, chemical mechanical polishing of bulk tungsten substrate was carried out. A 4 inch tungsten wafer was polished at the optimized condition with an average surface roughness of 4.63nm achieved. Bulk tungsten applications in packaging and micro-devices will be expanded.