Recombination losses of the photocurrent in Schottky barriers

In the present paper, the influence of recombination at the metal-semiconductor interface, in the space-charge region, and in the quasi-neutral volume on the Schottky-barrier photocurrent is analyzed within the framework of a thermionic-diffusion theory. A general expression for the photocurrent is derived, making allowance for the separation of the fluxes at the interface into recombination fluxes and diffusion to the metal. In the limiting case, this expression reduces to Gaertner's (1959) expression. The role of some sources of photocurrent losses in Au-GaAs Schottky barriers, with and without exposure to fast electrons, is studied experimentally.