INVESTIGATION BY SYNCHROTRON RADIATION OF InGaAs LASING STRUCTURES GROWN ON SiGe/Si PSEUDOSUBSTRATES

The growth of highly strained Quantum wells (QWs) on GaAs substrates are facilitated by the initial growth of a linearly graded InGaAs buffer. High-resolution X-ray diffractometry can supply overall information about the quality of the samples while X-ray topography provides both direct evidence of the absence or presence of single defects and visualization of their distribution. We present here a summary of studies performed on these InGaAs/AlGaAs QWs.