PHOTOLUMINESCENCE FROM SIGE SI QUANTUM DOTS WITH WAVELENGTH IN THE VISIBLE RANGE/

Photoluminescence from Si0.7Ge0.3/Si quantum dots with a wavelength in the visible range is reported. The SiGe/Si quantum dots were fabricat ed by electron beam lithography and reactive ion etching of an SiGe/Si superlattice. A photoluminescence spectrum was obtained between 4.2 K and room temperature. As the temperature increased, the photoluminesc ence intensity decreased, with the peak position shifting slightly to a higher energy. The photoluminescence persisted up to room temperatur e with its intensity similar to 40% of that at 4.2 K.