Effects of a linear arrangement of embedded Ge nanocrystals on an electron beam induced current

Abstract

We use a Monte Carlo algorithm to simulate the electron beam induced current collected from an n-doped silicon sample containing a linear arrangement of embedded Ge nanocrystals. These are described as spheres with a radius r and are assumed to have lower hole lifetime than the surrounding milieu. From a probabilistic point of view, the carrier trapping in each nanocrystal depends on its position referencing to the electron penetration volume. The collected current is studied as a function of the depth position of each nanocrystal and as a function of their density.The effects of the distance between successive nanocrystals is also studied. The results show that near a nanocrystal the collected current decreases with the decreasing of depth. This reduction is also controlled by the nanocrystal density and by the overlapping of the capture probability between nanocrystals. This overlapping is enhanced when the nanocrystals are close to each other.