INSITU STRESS MEASUREMENT OF CHEMICAL VAPOR-DEPOSITED TUNGSTEN SILICIDES

Peeling is a serious problem in chemical vapor deposited (CVD) tungsten silicide (WSi(x)). In situ stress measurement during annealing is performed for sputtered and CVD WSi(x) films at temperatures of 25-900-degrees-C. In monosilane reduced CVD WSi(x), intrinsic stress increases abruptly at 400-degrees-C and reaches a maximum of 7.8 x 10(8) Pa at 450-degrees-C. However, such abrupt stress changes are not found at low temperatures in sputtered and dichlorosilane reduced CVD films. Abrupt stress change appeared in monosilane WSi(x) at 400-450-degrees-C, which is a cause of peeling during annealing, may be due to the grain growth of hexagonal and tetragonal WSi2 grains.