ABSTRACT
Submicron carrier confinement structures have been grown on patterned GaAs(111)A substrates by molecular beam epitaxy (MBE) involving a single-step. The method is based on the amphoteric nature of Si dopants in GaAs growth. Cathodoluminescence (CL) spectra for the Si-doped GaAs layer grown on each patterned substrate show the formation of a lateral carrier confinement structure; the confined (111)A triangular region is p-type and the (311)A sidewalls are n-type. In the CL spectra of an A10.3Ga0.7As/GaAs single quantum well structure, strong emission from the confined region and lateral modulation of the peak wavelength are observed. This modulation is caused by a decrease in the GaAs well thickness due to Ga migration from the (111)A surface to the (311)A sidewalls. These results indicate that MBE growth on patterned GaAs(111)A substrates is a promising technique for achieving smaller structures such as quantum dots with novel carrier confinement.
