Münster 1997 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

HL: Halbleiterphysik

HL 40: Poster III

HL 40.13: Poster

Freitag, 21. März 1997, 11:00–14:00, Z

Photoluminescence studies of pseudomorphic Si_1−yC_y/Si MQW structures at low temperature and high pressure — •Z.X. Liu, A.R. Goñi, K. Manz, K. Syassen, K. Brunner, and K. Eberl — Max-Planck-Institut für Festkörperforschung, Heisenbergstr. 1, 70569 Stuttgart, Germany

We have measured photoluminescence (PL) spectra of pseudomorphic Si_1−yC_y/Si (y=0.45, 1.05, and 1.62%) multiple quantum well (MQW) structures under hydrostatic pressure (0-8 GPa) and at low temperatures (10-70 K). The MQW-related emission at energies below the Si band gap consists of free and bound exciton no-phonon lines and related Si-Si TO phonon replicas. All MQW-related PL peaks shift to lower energy with increasing pressure. The dependence of PL-peak intensities and energies on excitation density, temperature, and pressure are consistent with type-I band alignment in which both electrons and light holes are localized in the Si_1−yC_y layers. This alignment is independent of sample composition and applied pressure. Results for PL energies are compared to model calculations which take into account the effects of alloying as well as lattice mismatch.