Lattice absorption of Be-containing semiconductor alloys determined by spectroscopic ellipsometry

✍ Scribed by Wronkowska, A. A. ;Skowroński, Ł. ;Wronkowski, A. ;Zieliński, Ł. ;Firszt, F. ;Marasek, A. ;Paszkowicz, W. ;Arwin, H.

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 433 KB
• Volume: 205
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.200777774

✦ Synopsis

Abstract

Lattice absorption of Zn~1–x –y~ Be__~x~__ Mg__~y~__ Se and Cd~1–x –y~ Be__~x~__ Zn__~y~__ Se mixed crystals grown by a high pressure Bridgman method has been investigated by infrared spectroscopic ellipsometry in the wave number range from 230 cm^–1^ to 5000 cm^–1^. Ellipsometric spectra of Cd~1–x –y~ Be__~x~__ Zn__~y~__ Se crystals display features in the spectral range 350–550 cm^–1^ associated with BeSe‐type phonon modes. In the optical spectra of Zn~1–x –y~ Be__~x~__ Mg__~y~__ Se crystals both BeSe‐type and MgSe‐type lattice absorption bands are detected. The MgSe‐like modes are located at approximately 300 cm^–1^. The frequencies and oscillator strengths of optical phonon modes depend strongly on the alloy composition. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)