Reduced energy-angle dispersion of output electrons from a nanocrystalline Si emitter with a monolayergraphene surface electrode

Abstract

It is shown that the angle dispersions of output electrons of nanocrystalline silicon (nc-Si) quasiballistic electron emitter are significantly reduced by using a monolayer graphene as the surface electrode. This is closely linked with a remarkable enhancement in the emission efficiency and a suppression of the electron energy dispersion. The angle distribution curves become more directional at lower temperatures. These results are attributed to high transparency of monolayer graphene for quasiballistic electrons generated in the nc-Si layer. The intrinsic multi-tunneling cascade mode through nc-Si dots can be utilized most effectively by monolayer graphene surface electrode.