Nano epitaxial growth of GaAs on Si (001)

Abstract

Nano epitaxial growth (NEG) is used to develop GaAs monolithic hetero-epitaxy onto Si (001). For the GaAs grown in a nanopatterned trench with an aspect ratio of 5, the dislocations originally generated at the GaAs/Si interface are mostly isolated by the SiO2 sidewall. Compared with the conventional-planar Si substrate, implementing the NEG technique is able to decrease the dislocation density from about 109 cm−2 to almost zero. It is also confirmed that NEG is capable of confining the dislocations within the GaAs initial epitaxial layer (<100 nm), which meets the requirement of relatively less complicated epitaxial processes.