Substrate orientation effects in CdxHg1−xTe grown by MOVPE

The origin of hillocks in (Hg, Cd)Te grown by MOVPE

“…Epilayers grown onto (100) CdTe and (Cd,Zn)Te also have hillocks, although in this case they are less numerous than those on GaAs. 6 Hillock densities, in our hands and those of others, 16 are even higher on (100) indium antimonide (InSb) substrates than sodium free GaAs. Nor are hillocks restricted to layers grown by MOVPE.…”

“…This ties in with our observations from optical micrographs of cleaved edges of poor morphology layers that most hillocks in (Hg,Cd)Te/CdTe layers grown by MOVPE onto GaAs originate at the CdTe/GaAs inter- face and that these hillocks have been shown by secondary ion mass spectroscopy (SIMS) to contain higher gallium levels than the surrounding layer. The center of hillocks were reported by Capper et al 30 to contain higher than expected Cd levels.…”

Morphological defects of molecular beam epitaxy-grown CdTe and CdSeTe on Si

“…There is little difference between Cd-L α /Te-L α peak intensity ratios inside and outside the defect. Hillocks in CdTe compounds were believed to form during the initial stages of MBE 5 or metal organic chemical vapor deposition (MOCVD) 6 and to be related to substrate orientation and preparation. 1 The present study clearly shows that the morphological defects do not necessarily originate from the interface between the epitaxial layer and the substrate.…”

Metal-organic vapor-phase epitaxial growth of HgCdTe device heterostructures on three-inch-diameter substrates

“…The MOVPE growth is generally performed on substrates that are misoriented from the (100) by between 2°and 8°to minimize the size of pyramidalhillock growth defects. 8 The large lattice mismatch between GaAs and MCT necessitates the use of a CdTe-buffer layer. The substrate preparation and CdTe-buffer growth conditions exert a strong influence on the suppression of hillocks.…”