Wurtzite–zinc-blende polytypism in ZnSe onGaAs(111)A

Abstract

We have studied the wurtzite (W)–zinc-blende (ZB) polytypism in ZnSe films grown on the $\mathrm{}\left(111\right)A-\mathrm{oriented}$ substrates of GaAs. Although the stable structure of bulk ZnSe is ZB, W-structured ZnSe is formed near the interface on the ZB-structured $\mathrm{GaAs}\left(111\right)\mathrm{}A$ substrate. Our first-principles calculations have revealed that the charge state at the $\mathrm{Z}\mathrm{n}\mathrm{S}\mathrm{e}/\mathrm{G}\mathrm{a}\mathrm{A}\mathrm{s}\left(111\right)\mathrm{}A$ interface plays a key role in the formation of W-ZnSe. We show that the structural quality of W-ZnSe is significantly improved using a cracked Se source, while ZB-ZnSe is grown using a vicinal $\mathrm{GaAs}\left(111\right)\mathrm{}A$ substrate.