Visible band-gap ZnCdO heterostructures grown by molecular beam epitaxy

Abstract

Single-phase ZnCdO alloys with a band gap extending from the violet to yellow spectral range are fabricated by molecular beam epitaxy using extremely low growth temperatures in conjunction with O-rich growth conditions. The Cd concentration can be systematically adjusted via the Cd∕Zn beam pressure ratio. Despite growth temperatures as low as 150°C, layer-by-layer growth is accomplished allowing for the preparation of ZnCdO∕ZnO quantum well structures. Both epilayers and quantum wells exhibit strong band-gap-related emission at room temperature in the whole composition range.