SURFACE PHOTOVOLTAGE SPECTROSCOPY OF QUANTUM-WELLS AND SUPERLATTICES

Surface photovoltage spectroscopy (SPS) has been employed to monitor o ptical transitions in quantum well and superlattice structures at room temperature. Excellent agreement is found between theoretical predict ions of heavy hole and electron energy level positions and the observe d transitions. The results show that using this technique, the complet e band diagram of the quantum structure may be constructed. SPS emerge s as a powerful tool capable of monitoring optical transitions above t he lowest one in a simple to interpret, contactless, and nondestructiv e way. (C) 1996 American Institute of Physics.