THIN OXIDE INTERFACE LAYERS IN A-SI-H MIS STRUCTURES

Pd-metal/insulator/semiconductor based on hydrogenated amorphous silic on were produced by plasma enhanced chemical vapour deposition with tw o different oxidised surfaces: thermal in ambient air and chemical wit h hydrogen peroxide. The diode characteristics have been investigated using dark and light current as f(upsilon) measurements in the tempera ture range from 300 K to 380 K, from which it was possible to infer th e electron barrier height. The data obtained show that the incorporati on of a thin insulator layer between the semiconductor and the metal i mproves the performances of the devices by preventing the formation of silicides at the interface. Apart from that we also show that the MIS structures with the thermal oxide presents 'better' performances than the ones with the chemical oxide due to the type of interface states and of the oxide charges associated with the interface between the ins ulator and the semiconductor. (C) 1998 Elsevier Science B.V. All right s reserved.