Electrical and Optical Properties of Si Doped GaAs Grown by Molecular Beam Epitaxy on (311) Substrates

Abstract

The electrical and optical properties of Si-doped GaAs grown on GaAs (100), (311)A and (311)B substrates by molecular beam epitaxy (MBE) have been studied. A mirror smooth surface is observed for each orientation at low Si atom concentration. Electrical and optical characteristics of the (311)A sample are similar to Si-doped p-type GaAs grown by liquid phase epitaxy, while (311)B samples show almost the same characteristics as (100) samples. Even for a Si atomic concentration up to 1×10 20 cm -3 , which is too high to keep good surface morphologies of (100) and (311)B samples, excellent morphologies of (311)A samples were obtained. This orientation dependence may be due to different site occupations of Si atoms and surface atom configurations around Si atoms during MBE growth.