GROWTH-STUDIES ON IN0.5GA0.5AS ALGAAS QUANTUM-WELLS GROWN ON GAAS WITH A LINEARLY GRADED INGAAS BUFFER/

High indium content InGaAs/AlGaAs quantum wells (QWs) are useful for m odulator and intersubband applications. Growth of these highly straine d QWs on GaAs has been facilitated by the use of a linearly graded InG aAs buffer. We present here growth studies performed on these QW struc tures. Buffer parameters including buffer substrate temperature, buffe r grading rate, and final buffer indium composition are studied. QW pa rameters including QW substrate temperature, the use of GaAs interface smoothing layers, and barrier substrate temperature are also investig ated. Using near optimized growth conditions, narrow linewidth intersu bband transitions are demonstrated.