Ultrafast and high-sensitivity photovoltaic effects in TiN/Si Schottky junction

Ultrafast photovoltaic effects with high sensitivity in both vertical and lateral directions have been observed in the TiN/Si Schottky junction. The open-circuit vertical photovoltage across the junction is 400 mV under irradiation of an HeNe laser with a power of 7 mW. The response speed is in the picosecond order. Furthermore, we found a large lateral photovoltage (LPV) parallel to the plane of the junction. The LPV between the two electrodes on the Si substrate of the junction depends linearly on the position of the incident laser spot. And the highest position sensitivity is 60 mV mm^-1 over the displacement of the laser spot. These characteristics indicate the potential applications of the TiN/Si junction in photodetectors and position sensitive detectors.