Strategic Molecular Beam Epitaxial Growth of GaAs/GaAsBi Heterostructures and Nanostructures

Abstract

In this chapter, we go over epitaxial growth of bismide thin films, multiple quantum wells, and nanostructures (nanowires) using molecular beam epitaxy (MBE) and their surface morphology, structural, and optical properties are investigated along with device applications. We describe how the Bi content in GaAs1−xBix epilayers grown on (100), (411)A, and (411)B GaAs substrates can be controlled by the growth conditions. Nonstandard growth conditions such as two-substrate-temperature technique (TST) are required for GaAs1−xBix because of the strong tendency of Bi atom segregation under usual growth conditions. We have reported a GaAs0.96Bi0.04/GaAs multiple quantum well LED grown by TST technique with a room temperature photoluminescence and electroluminescence at 1.23 μm emission wavelength. The TST procedure proves as a very efficient method to reduce Bi segregation and thus improves the quality of the GaAsBi layer at GaAs interfaces.