Determination of the band-gap of MgS and MgS-rich Zn1-xMgxSySe1-y alloys from optical transmission measurements

作者：Davidson Ian A^*; Moug Richard T; Izdebski Frauke; Bradford Christine; Prior Kevin A

来源：Physica Status Solidi B-Basic Solid State Physics, 2010, 247(6): 1396-1398.

DOI：10.1002/pssb.200983190

• II-VI semiconductors
• absorption spectra
• X-ray diffraction

As part of our development of an epitaxial lift-off process, utilising a sacrificial magnesium sulphide (MgS) layer, we have developed a MgS-rich ZnMgSSe alloy which provides excellent carrier confinement and resists both oxidation and acid attack. Here the optical transmission of the alloy has been measured and its bandgap determined as a direct transition at 4.19 +/- 0.04 eV. Its composition has also been determined by X-ray interference (XRI) and comparison with simulations. For a range of alloy samples we obtain compositions of the Zn1-xMgxSySe1-y layers which are (x, y) = (0.80 +/- 0.02, 0.645 +/- 0.025). Using the alloy bandgap and composition we have determined direct bandgap transition energy for MgS by extrapolation. This is found to be 4.78 +/- 0.14 eV.

• 出版日期2010-6