Ar. Clawson et Cm. Hanson, STRAIN FROM MODIFIED INTERFACE COMPOSITIONS IN INGAAS INP SUPERLATTICES/, Journal of electronic materials, 24(6), 1995, pp. 781-786
Thin strained regions have been inserted at the interfaces of lattice-
matched InGaAs/lnP superlattices to assess growth conditions for tailo
ring of localized compositional changes and for studying As-P intermix
ing behavior during heterojunction growth. Also, precise growth rates
of binary composition layers were determined from specially designed s
uperlattices using strained layers of common anion compounds inserted
periodically into InP and GaAs. Growth rates of fractional monolayers
are found to be identical to thick layer growth rates. When thin InAs,
GaAs, GaP, AlAs, or AIP layers were inserted at the InGaAs/InP hetero
junctions, the measured strain at either one or both interfaces was eq
ual to the strain predicted from the growth rate x time product. Exces
s strain seen in some cases is due to a change in As-P intermixing and
this component can be separated from the predicted strain. Insertion
of Ga-compounds at the InP-grown-on-InGaAs interface causes interface
roughening which degrades the superlattice. For all other compositions
the thin, highly strained regions are not detrimental to the crystall
ine quality of the periodic structure.