Study of hole miniband transport in GexSi1-x/Si superlattice

Summary form only given. The authors report the observation of hole-miniband transport in symmetrically strained Ge_xSi_1-x/Si superlattices. Two different kinds of superlattice sample were grown and fabricated. The first kind of sample consists of a single superlattice layer grown on an unstrained Ge_x2/ Si_1-x2//Si buffer layer. The second kind of sample is called BAS (band aligned superlattice) and consists of two superlattices having different minibands. Mesa diodes of 50-100 mu m in diameter were fabricated for electrical measurement. For the simple superlattice sample, current voltage (I-V) characteristics for forward and reverse biases are almost symmetric. For the BAS sample, asymmetric I-V characteristics similar to those of a p-n junction are observed. The use of Ge_xSi_1-x/Si superlattices for device applications in infrared detectors and infrared sources using optical transitions between minibands is suggested.