The superconductor-semiconductor Schottky barrier diode detector

Abstract

The superconductor‐semiconductor contact diode, or super‐Schottky‐barrier‐diode, has been examined theoretically and experimentally as a video detector of high‐frequency radiation. The measured noise‐equivalent power (NEP) of the device is believed to be the smallest value ever reported in the literature for video detection. Moreover, the high reliability established for the ordinary Schottky barrier diode is in evidence for the proposed diode. The doping of the semiconductor is chosen large enough so that electron tunneling dominates the volt‐ampere behavior of the diode. As such, for T < T_c and V < Δ, the diode exhibits a high degree of nonlinearity in its volt‐ampere characteristic. It is this nonlinearity that the super‐Schottky‐diode exploits. Initial results with p‐type GaAs at 1 °K have yielded an NEP of 2 × 10⁻¹⁵ W/Hz^1/2 at 10 GHz.