Conduction Mechanisms In Crystallized Silicon Films On Molybdenum Substrates

Abstract

ABSTRACTHydrogenated Amorphous silicon films deposited on molybdenum sheet metal substrates have been crystallized by thermal annealing at 850°C for 4 hours in a nitrogen atmosphere. X-ray diffraction and scanning electron microscopy results indicated that the average grain size in the crystallized films was approximately 200A. Palladium contacts were fabricated and the resulting Pd/Si/Mo structures were electrically characterized. Current-voltage-temperature measurements for phosphorus doped and undoped annealed samples resulted in a J “V characteristic consistent with space-charge-limited current. Using this data, Mobility as a function of temperature from 100K-300K was obtained. In phosphorus doped samples, the mobility appeared to be limited by energy barriers at the grain boundaries. In undoped samples, a σ “T’ exp (-b/T’) temperature dependence consistent with variable-range hopping conduction was observed.