SPECTROSCOPIC ELLIPSOMETRY STUDIES OF EXCITONIC FEATURES AND OPTICAL FUNCTIONS OF ALXGA1-XAS/GAAS MULTIPLE QUANTUM WELL STRUCTURES

Spectroscopic ellipsometry has been shown to provide a rapid, room-temperature, non-destructive assessment technique for quantum well structures ranging from a single well to 100-period structures. Barrier and well thicknesses and self-consistent quantised transition energies have been determined from a single measurement. Good agreement for the first three transition energies was obtained for a series of well widths, using a 65% conduction band offset. Modelling the spectra by using individual layer bulk dielectric functions and by effective layer approximations has been compared. The optical functions of a single 50Å well structure have been determined. © 1990 AIME.