Molecular beam epitaxial growth of InAs/(Al, Ga)Sb quantum-well structures on germanium substrates

Publisher Website
Google Scholar
Abstract
Growth of InAs/(Al, Ga)Sb quantum-well structures was performed on germanium substrates by molecular beam epitaxy. The structural and electrical quality was characterized by x-raydiffractometry,transmission electron microscopy, and Hall transport measurements. An optimization of the GaAsbuffer layergrowth enabled the deposition of InAs/Al 0.2 Ga 0.8 Sb quantum wells with electron mobilities of 27 500 cm2/V s at 300 K and 260 000 cm2/V s at 4.2 K. These values are comparable to those measured for identical structures grown on GaAs substrate. Our results demonstrate the feasibility of using germanium as an alternative cheap substrate instead of commonly used GaAs for the growth of InAs/Al 0.2 Ga 0.8 Sb quantum-well magnetic sensor devices.