Surface nano structures on W surface exposed to low-energy high flux D plasma

Abstract

The surface nano structures on W surface exposed to low-energy D plasma was studied by transmission electron microscopy. It was found that the surface nano structures on W surface induced by D plasma were mainly due to two reasons. First, the subsurface nano-sized bubbles will induce nano scale blistering of the surface, resulting in surface nano morphology. The nano scale blistering behaviour is most obvious on [1 1 1] surface at low temperature (500 K). Secondly, during the plasma exposure, oxide layer on W surface will be sputtered by low energy D particles, and the sputtering can also induce nano structures on some surfaces. At low temperature (500 K), the surface nano structures were formed due to the nano scale blistering behaviour and the sputtering of surface oxide layer. At high temperature (1000 K), the surface nano structures were mainly caused by the sputtering of surface oxide layer.