Room temperature electroluminescence from a nanocrystalline diamond/Si heterojunction

We report on the fabrication and characterization of the room temperature electroluminescence of heterojunction between nanocrystalline diamond film (NDF) and heavily doped n-type single crystalline silicon (n(+)-Si) substrate. The current-voltage characteristics (I-V) of the NDF/ n(+)-Si heterojunction show clear rectification properties. Importantly, with sufficiently high forward bias applied on the NDF/n(+)-Si heterojunction, fairly strong visible electroluminescence (EL) was obtained at room temperature. The EL occurred as the consequence of the electrons tunneling from the n(+)-Si into the NDF. An energy-band model has been proposed to understand the mechanism of the I-V characteristics and the EL for the NDF/n-(+)-Si heterojunction. (c) 2006 Elsevier B.V. All rights reserved.