ZnSe heterocrystalline junctions based on zinc blende-wurtzite polytypism

Abstract

ZnSe zinc blende-wurtzite (ZB-WZ) heterocrystalline junctions were successfully fabricated via pressure variation during the thermal evaporation process and characterized using electron microscopy techniques. Two types of ZB-WZ junction configurations were observed, and the orientation relationships, denoted as [111̄] ZB //[0001]WZ (type I) and ±[111] ZB//[0001] WZ(type II), respectively, were determined in detail by systematic parallel beam selected area electron diffraction combined with stereographic projections. The relatively weak polarities on both sides of such junctions were also detected using convergent beam electron diffraction combined with simulation. Different from the ideal models suggested by the theoretical studies on the (111) ZB-(0001) WZinterface of ZnSe (even other II-VI semiconductors), the present results indicate the existence of the polarity reversal across the junctions, which may result in charge accumulations around the interfaces. Therefore, it offers an interesting real system for theoretical investigation on such polytypic interface and also an appropriate experimental platform for further electrical transport measurement across these junctions. Copyright © 2010 American Chemical Society.