Modification of the donor-acceptor-pair luminescence in doped multi-thin film structures

A single crystal multi-thin film structure consisting of films with both donor and acceptor doping to almost compensation, and separated by intrinsic semiconductor layers of a thickness governed by the Bohr radius of the donor electron, is analyzed with respect to a possible modification of the Donor-Acceptor-Pair (DAP) luminescence band.Pronounced jumps in the DAP-distribution curve and consequently in the luminescence intensity band with spacings of the intrinsic layer thickness are manifested, which are the result of Coulomb interaction between donors of the one and acceptors of the neighbouring doped films. This photoluminescence property, not yet documented in the literature, can advantageously be used for the analysis of doped superlattice films. Doping layers of the described kind may even be introduced as probes in order to study the initial steps of diffusion or migration of impurity atoms into the bulk in luminescence active semiconductor materials.