Electric field effect in amorphous semiconductor films assembled from transition-metal-encapsulating Si clusters

ABSTRACTWe synthesized amorphous semiconductor films composed of Mo-encapsulating Si clusters (MoSin : n∼10) on solid substrates. The MoSi10 films had Si networks similar to hydrogenated amorphous Si and an optical gap of 1.5 eV. Electron spin resonance signals were not observed in the films indicating that dangling bonds of Si were terminated by Mo atoms. We fabricated thin-film-transistors using the MoSi10 film as a channel material. The electric field effect of the film was clearly observed. This suggests that the density of mid-gap states in the film is low enough for the field effect to occur.