Metalorganic vapor phase epitaxy of InAs layers on GaAs substrates using low-temperature growth of InGaAs graded buffer layers

InAs layers were grown on GaAs substrates by metalorganic vapor phase epitaxy using InGaAs graded buffer layers and two-step growth. Layer quality was investigated by transmission electron microscopy. The threading dislocation density in InAs grown with the graded buffer layer was determined to be 1.6 × 107 cm-2. That value was one order of magnitude lower than that of InAs layers grown by two-step growth. Graded buffer layer growth is more effective for InAs layers on GaAs substrates with low threading dislocation density than two-step growth.