Geometrical Characteristics and Surface Polarity of Inclined Crystallographic Planes of the Wurtzite and Zincblende Structures

Abstract

Inclined crystallographic planes of the wurtzite structure were investigated in comparison with the zincblende structure in terms of surface geometry characteristics. The ball–stick model indicates that the semipolar $$ \left( {1{\bar 1} 01} \right) $$ surface possesses a surface polarity resembling the anion polarity, which agrees with the common experimental observations of epitaxial growth preference for the cation-polarity $$ \left( {1{\bar 1} 0{\bar 1} } \right) $$ surface over the $$ \left( {1{\bar 1} 01} \right) $$ surface. The wurtzite $$ \left\{ {11{\bar 2} 2} \right\} $$ surface was found to share geometrical similarities with the zincblende {100} surface uniquely among the possible semipolar planes. This finding encourages epitaxial growth on the $$ \left\{ {11{\bar 2} 2} \right\} $$ plane of wurtzite semiconductors, e.g., GaN, with the potential of avoiding atomic step formations typically associated with off-axis crystallographic planes.