Double frequency absorption induced by Al-Si schottky barrier potential and mechanism of two-photon response

By observing two-photon response and anisotropy of the light-induced voltage in Si-Al Schottky barrier potential of the Si MSM (Metal-Semiconductor-Metal) planar structure two-photon response optical detector. It is certified from the experimental and theoretical analysis that the built-in electric field generated by the Schottky barrier potential will induce the phenomena of optical rectification in Si photodiode. Thus, it is deduced that there must be double-frequency absorption (DFA) caused by phase-mismatch in the mechanism of two-photon response of Si photodiode. If the intensity of the built-in electric field is strong enough, the DFA will be the main feature of the two-photon response.