INP ON SI(111) - ACCOMMODATION OF LATTICE MISMATCH AND STRUCTURAL-PROPERTIES

The growth of InP by low-pressure metalorganic chemical vapor depositi on on vicinal Si(111), misoriented 3 degrees towards [<(11)over bar>1] , is reported. By double crystal x-ray diffraction an order of magnitu de improvement in structural quality is measured as compared to InP on Si(001). From high resolution electron microscopy near the interface a heavily twinned region of 25 nm in thickness is found with microtwin s having their twin planes parallel to the Si(111) surface. In this re gion the 8% misfit between InP and Si is completely accommodated in on e dimension by partial dislocations having Burgers vectors a/6[112] (S chockley partial dislocations) in the (111) surface plane which are as sociated with the formation of the thin twinned region close to the in terface. Above this zone the crystallographic orientations of the InP are identical to those of the Si substrate.