This research project is concerned with the innovative growth of new combinations of materials and creative methods for characterization and quality assessment of these new materials systems for use in ultra fast optoelectronic communication and switching systems. Cadmium telluride (CaTe) layers will be grown on gallium arsenide/silicon (GaAs/Si) substrates. The use of GaAs/Si substrates offers the possibility of exploiting the fast optoelectronic circuitry of BaAs and established silicon VLSI technology. Combinations of GaAs and mercury CaTe will be investigated in the creation of a monolithic infrared detector system. Photoluminescence (PL) which is a well known characterization technique will be combined with new ideas to characterize the film quality and to correlate defects with the film growth conditions. The approach centers around spatially controlling the area where the luminescence emanates from the sample. Photoluminescence is to be combined with electroluminescence and geometrical arrangements of pn junctions in order to confine and control carriers in areas of importance. The combination of luminescene techniques provides the injection of excess carrier from different parts of the sample and the pn junctions confine the carriers with built-in electric fields. Some new approaches to the characterization of thin layers from the combined used of photo and electroluminescence in unique ways can be anticipated.
