Model for the linear electro-optic reflectance-difference spectrum of gaas(001) around (formula presented) and (formula presented)

We developed a model to describe the linear electro-optic (LEO) component of the reflectance-difference (RD) spectrum of zinc-blende semiconductors for energies around the (Formula presented) and (Formula presented) critical points. The model is based on a piezoelectric effect due to the semiconductor surface electric field and predicts a LEO line shape given by the superposition of two terms, a first one proportional to the energy derivative of the reflectance spectrum and a second one associated with the undifferentiated reflectance spectrum. We compared the predictions of the model to experimental LEO line shapes for molecular-beam epitaxy GaAs(001) layers doped with (Formula presented) Si donors and found an excellent agreement. The results reported in this paper help develop the LEO RD spectroscopy as a characterization tool for zinc-blende semiconductors. © 1999 The American Physical Society.

VIVO