LAUSR

Abstract Usually, the conductivity of semiconductor can be increased after phosphorus (P) doping but the electron mobility will be obviously reduced due to the strong impurity scattering. Here, we report a novel phenomenon that the carrier mobility in Si nano-crystals is significantly enhanced after nanoscale P doping. It is found that the electron mobility reaches to 30.3 cm 2 /V s, which is improved by one order of magnitude compared with that of un-doped one (1.6 cm 2 /V s), while the room temperature conductivity is as high as 1.5 × 10 3  S/cm by appropriately P doping. The clear experimental evidences are present to demonstrate that both the reduction of barrier height of grain boundaries and the surface defects states due to P doping improve the corresponding electron mobility in nano-crystalline Si films.