Abstract
Thin, perfectly strained quantum wells of indirect band gap between GaP on (111)B-oriented substrates have been grown by metal-organic vapor phase epitaxy. The layers were characterized by low-temperature photoluminescence and by electroreflectance. The evolution of the transition energies of the X and Γ conduction-band minima to the valence-band maxima was investigated, as a function of arsenic concentration up to 36% arsenic and compared to a model that treats strain as well as quantum confinement effects. Since the samples are grown in the [111] direction, strain-induced piezoelectric fields are expected to be present. The influence of this field on the experimental transition energies is discussed. Evidence of the ionization of neutral donors by the piezoelectric field is presented. The layers are concluded to be type I. The photoluminescence emission is very similar to bulk and includes the emission.
- Received 17 July 1992
DOI:https://doi.org/10.1103/PhysRevB.47.6408
©1993 American Physical Society