Influence of nitrogen partial pressure on morphology, structure and transport properties of reactive sputtered polycrystalline TiN films

摘要

The surface morphology, structure and electrical transport properties of the polycrystalline TiN films fabricated using reactive sputtering at different N_2 partial pressures (P_(N_2) have been investigated systematically. The films grow with the preferred (200) orientation. The room-temperature resistivity first deceases, then slightly increases with the increase of P_(n2). The minimum room-temperature resistivity is about 1.7 x 10~(-3) Q cm at P_(n2) = 0.5 Pa. The low temperature conductance mechanism turns from tunneling across the grain boundaries to variable-range hopping as P_(n2) increases. The decreased density of states at E_F with the increase of N vacancies should be the reason for the increased resistivity of the films fabricated at different P_(N2).