GEOMETRICAL FACTOR IN MULTIINTERFACE HOMOSTRUCTURES

In an experimental investigation carried out on multilayer silicon hom ostructures (of the n+-n-n+ type) an electric interaction between the two homointerfaces through majority carriers as a function of the geom etrical factor has been shown. The two model homointerfaces were forme d in the same monocrystal (CVD epitaxy) by only an abrupt change in th e impurity doping level. Samples differing in the spacing of their par allel interfaces were characterized in the stationary and steady state s (static and quasi-static regimes) to reveal modifications in their m acroscopic transport. It has been demonstrated that the thermionic emi ssion current, normally taken into account in the barrier transport (w ith large potential barriers) dominates in only two of five characteri stic bias intervals. The two other phenomena, also related to the geom etrical factor, i.e. the diffusion-drift and tunneling currents, domin ate the conduction over practically the whole dc-bias range. These res ults allow the study of short and long range electrical interactions a s well as the free carrier micromovement of simple and complex semicon ductor interfaces of multilayer devices.