Morphology Changes of Platinum and Tungsten Carbide by He Plasma Irradiation

Fuzz nanostructure formation on metal by helium plasma irradiation has potential in industrial application due to the increasing in surface area. We have investigated the influence on the surfaces of platinum and tungsten carbide by helium plasma irradiation. On tungsten carbide, fuzz nanostructure was formed when the surface temperature was higher than 1000 K. However, when helium irradiation was conducted at the surface temperature of 940 K or higher, tungsten carbide changed to W possibly because of radiation enhanced sublimation. On platinum, fuzz nanostructure was formed when the surface temperature was in the range of 800 - 1000 K and the fluence was on the order of 1026 m−2. The nanostructure formation mechanism of platinum should be similar to that of tungsten, but incubation fluence of platinum was higher and the growth rate of fuzzy layer was likely to be lower than those of tungsten.