Surface emission from the interface of n-Si/p-diamond heterojunction

High quality, boron-doped, chemical vapour deposited (CVD) diamond films we re grown by microwave CVD onto single-crystal nc-silicon with dopant concen trations ranging from 100 ppm to 1000 ppm. Electron emission results and co ntact resistance measurements were recorded by applying bias voltage across the n-p junction. The current-voltage data obtained were then curve fitted to a number of conduction formulae to establish whether there was a strong er correlation with conduction mechanisms other than the Fowler-Nordheim fo rmula. It was concluded that the data supported the possibility that conduc tion across the n-p junction by forward bias was attributable not to minori ty carriers but to stepwise tunnelling via interface states according to th e model proposed by Riben-Feucht. The stable and high current density surfa ce emission was also observed from the interface of the n-p junction under forward bias condition, which can be switched on with a bias voltage of aro und 1 V.