Effect of the surface recombination and the depletion region on the electron beam induced current at a Schottky nanocontact

An analysis of the depletion region that is induced in a semiconductor by a circular nano Schottky contact perpendicular to the electron beam is presented. The electron beam induced current (EBIC) collection efficiency η was calculated using a Monte Carlo simulation (MCS) approach. The nano Schottky of radius r_c is surrounded by a zero or an infinite surface recombination velocity (v_s = 0 or v_s = ∞). The depletion region of the contact has a hemispherical form of radius z _D. The EBIC was obtained by simulating the random diffusion and collection of the minority carriers that are generated at point-like sources S_i randomly distributed within the generation volume. The profile of the EBIC collection efficiency versus the distance to the nanocontact is obtained. The results show that the values obtained for v_s = 0 are greater than those obtained for v_s = ∞ and increase with the increase of z_D.