Le Journal de Physique IV 03 (1993) C5-119-C5-122
Photoluminescence from Si/Si0.87Ge0.13 multiple quantum well wiresY.S. TANG1, C.M. SOTOMAYOR TORRES1, C.D.W. WILKINSON1, D.W SMITH2, T.E. WHALL2 and E.H.C. PARKER2
1 Nanoelectronics Research Centre, Department of Electronics and Electrical Engineering, University of Glasgow, Glasgow G12 8QQ, U.K.
2 Department of Physics, University of Warwick, Coventry CV4 7AL, U.K.
This paper reports a low temperature photoluminescence study of the optical properties of a series of dry etched free standing strained layer Si/Si0.87Ge0.13 multiple quantum well wires with lateral dimensions between 40nm and 500nm. The results show that dry etching induces partial strain relaxation. An enhanced electron-hole droplets emission from the Si layers with reducing wire width was observed due to both the extra surface roughness introduced during the etching process, which accelerates the nucleation of the droplets formation, and the effect of lateral confinement. A new feature at 1.131eV at 4K related to unknown impurity states located at the heterointerfaces was also detected.
© EDP Sciences 1993