INTENSE PHOTOLUMINESCENCE OBSERVED IN MODULATION-DOPED SI SIGE QUANTUM-WELL STRUCTURES/

p-type modulation doped wide Si/SiGe quantum well (QW) structures have been grown using a solid-source molecular beam epitaxy system. Very i ntense SiGe-related photoluminescence (PL) peaks, more than an order o f magnitude stronger than for undoped SiGe QW structures, were observe d from these samples. The increased PL intensity is believed to be due to the electron confinement in the vicinity of the QW, which enhances its excitonic recombination process in the Sice layer, and it also in dicates high crystalline quality of tile grown materials with low inco rporation of non-radiative defects. The luminescence properties of the se modulation doped SiGe well structures have been studied under vario us excitation and measurement temperature conditions. Differences in P L spectra from MBE and some CVD grown Si/SiGe samples are discussed.