Resistivity and structural defects of reactively sputtered TiN and HfN films

TiN and HfN thin films have been deposited by reactive r.f.-sputtering in an Ar-N(2) gas mixture under different condition of total gas pressure (P(T)) from 0.7 Pa to 5.3 Pa. Thin him X-ray diffraction studies show that the structure of the TiN films is gradually changed from TiN f.c.c. structure to amorphous with increasing P(T). On the other hand, HfN f.c.c. structure with a strong (111)-preferred orientation is formed for all HfN films prepared with various P(T) The resistivity of the films at room temperature (rho(RT)) increased with increasing P(T) in different ways between TiN and HfN. The films with rho(RT) less than or equal to 0.3 m Omega m show root T dependence in conductivity at low temperature. HfN films with rho(RT) = 1.6 m Omega m, the largest one measured, show an insulating behavior. The magnetoconductance Delta sigma(H) measurements showed that the spinorbit coupling of HfN is found to be stronger than that of TIN. (C) 1999 Elsevier Science S.A. All rights reserved.