High quantum efficiency InP mesas grown by hybrid epitaxy on Si substrates

Selective area liquid phase epitaxy of InP mesas has been performed on masked Si(001) substrates previously overgrown with InP by metalorganic chemical vapour deposition (MOCVD). The resulting mesas are bordered by very smooth crystal facets which are free of defects over typically 300 μm and exhibit an etch pit density of ≤1 × 104 cm−2. The X-ray rocking curve half width of the mesas amounts to 144 arcsec and the quantum efficiency is increased by two orders of magnitude as compared to the underlying InP buffer layer. Thermally induced strain is observed by triple X-ray analysis to relax anisotropically in perfect agreement with finite element analysis. These results are encouraging to use the selectively grown mesas as buffer layers for device structures to be grown in a subsequent MOCVD process step.