The optimization of metal-semiconductor light detection by Schottky interface image force

The metal-semiconductor interface structure, which can convert photon energy into electrons by internal photon-emission effect, is utilized as one kind of photodetectors. In the Schottky device, the barrier limits the detectable wavelength and the detection response, so how to amplify the detection signal is an important issue. Here, we first quantify the effect of applied bias on the energy barrier reduction mechanism from a mathematical equation. Furthermore, we fabricate metal/semiconductor Schottky devices and experimentally demonstrate the optimization of optical response by image-force lowering effect. As a result, experiment showed a 21 times enhancement in responsivity after an image-force lowering effect was induced.