US Patent 7718117 Tungsten sputtering target and method of manufacturing the target

A method of manufacturing a tungsten sputtering target includes pressing a high purity tungsten powder to form a pressed compact, first sintering the pressed compact at a temperature of 1450-1700° C. for one hour or longer after the pressed compact is heated at a heating-up rate of 2-5° C./min on the way to a maximum sintering temperature, second sintering the pressed compact to form a sintered body at a temperature of 1900° C. or higher for 5 hours or longer, working the sintered body to obtain a shape of a target, subjecting the target to a grinding work of at least one of rotary grinding and polishing, and subjecting the target to a finishing work of at least one of etching and reverse sputtering.