Abstract

Interest in the growth of high quality GaAs on Si substrates originates from its potential application in optoelectronic devices and optoelectronic integrated circuits [1]. A promising method for the epitaxy of GaAs on Si is epitaxial lateral overgrowth (ELO). The main advantage of this approach is that dislocations are effectively blocked by the masking film and the laterally grown parts of ELO layers will be nearly defect free. In addition, the mismatch strain will be distributed in three dimensions for the epitaxy on patterned substrates. However, coalescence of the ELO GaAs fronts by metalorganic vapor-phase epitaxy (MOCVD) to provide high-quality and large-scale GaAs layers for device fabrication has not been achieved. This paper optimizes the pre-epi cleaning process and the growth procedures to obtain widespread GaAs layers with high-quality.

© 2015 IEEE