화학공학소재연구정보센터
Thin Solid Films, Vol.564, 110-114, 2014
Redundant Sb condensation on GaSb epilayers grown by molecular beam epitaxy during cooling procedure
The effect of four different cooling receipts on the surface morphologies of unintentionally-doped GaSb epilayers on GaSb (100) substrates grown by molecular beam epitaxy is reported. Those receipts include three different Sb beam equivalent pressure (BEP) levels and two different termination temperatures. Surface morphologies of epilayers were examined by wet etching, surface profiler, atomic force microscopy, scanning electron microscopy and Raman spectroscopy. The results demonstrate that during the cooling period, a Sb BEP of 4.00 x 10(-4) Pa at a termination temperature of 400 degrees C induces a smooth surface without Sb condensation whereas same Sb BEP at a termination temperature of 350 degrees C forms a 300 nm thick Sb layer on the surface. In addition, it is revealed that by applying a wet etching procedure and using a surface profiler it is possible to identify this condensed layer from the two-sloped feature of mesa profile. (C) 2014 Elsevier B.V. All rights reserved.