Distributions of growth rates on patterned surfaces measured by scanning microprobe reflection high-energy electron diffraction

Abstract

Microscopic distributions of growth rates on GaAs(001) layers next to (111)A and (111)B surfaces were measured in real time during molecular beam epitaxy growth by scanning microprobe reflection high-energy electron diffraction. The increase in the growth rate on the GaAs(001) surface near the edge of (111)A surfaces is observed and the decrease in the growth rate on the GaAs(001) surface near the edge of the (111)B surfaces is found out. The exponential variation of the growth rate as a function of the distance from the edge, reflects surface diffusion of Ga atoms. The diffusion lengths along the [110] and [1̄10] directions are estimated to be about 1 and 8 μm at 560 °C, respectively.