Temperature Dependency of Schottky Barrier Parameters of Ti Schottky Contacts to Si-on-Insulator

Abstract

We have investigated the temperature-dependent current–voltage (I–V) characteristics of Ti Schottky structure on the Si-on-insulator (SOI) in the temperature range of 175–375 K by steps of 25 K. As decreasing temperature, the barrier height and ideality factor of Ti/SOI Schottky contact were found to be decreased and increased, respectively, indicating a considerable deviation from the ideal thermionic emission model in its current conduction mechanism. From the linear relationship between the barrier heights and ideality factors, the homogeneous barrier height was calculated to be 0.76 eV. The mean barrier height of 0.87 eV and the modified Richardson constant value of 30.63 A·cm⁻²·K⁻² were obtained using modified Richardson plot. On the basis of a thermionic emission mechanism with a Gaussian distribution of the barrier heights, the temperature-dependent I–V behavior of Ti/SOI Schottky contact was explained in terms of barrier height inhomogeneities at the interface between Ti and SOI.