The role of surface adsorbates in the metalorganic vapor phase epitaxial growth of (Hg, Cd) Te onto (100) GaAs substrates

It has been established that a compound present as an impurity in the propan-2-ol used in the preparation of GaAs (100) substrates for the metalorganic vapor phase epitaxy growth of (Hg,Cd)Te has a marked effect on the crystalline perfection and surface morphology of the resulting layers. In particular, the presence of this species, which contains Na, ensures that (i) the epitaxial overgrowth is of (100) orientation without the need for ZnTe nucleation layers, and (ii) the density of pyramidal hillocks on the surface can be reproducibly < 10 cm−2.