Dopant redistribution during the formation of tungsten disilicide by rapid thermal processing

Abstract

We studied arsenic redistribution with annealing time in the SiW system during the formation of WSi2 by rapid thermal processing at 850 °C. The silicon was arsenic doped and the tungsten was deposited by sputtering. A significant amount of arsenic diffuses back and segregates at the WSi2Si interface, the remainder is incorporated in the disilicide. This behavior is quite different from that of boron, which diffuses simultaneously to the silicon through the disilicide layer.