Surface photoabsorption (SPA) is an in situ technique for monitoring III-V
semiconductors in an MOVPE reactor. When used in conjunction with UV absorp
tion, it gives information about the strain associated with the growth of i
deal (one monolayer) and nonideal (more than one monolayer) GaAs interfaces
in InAs/GaSb superlattices. Raman scattering has been used as an ex situ t
echnique for quantifying the strain in these superlattices. It is found tha
t the LO frequency blue shifts by 3 cm(-1) when nonideal interfaces are gro
wn. (C) 1998 Elsevier Science B.V. All rights reserved.