C. Michelakis et al., Comparison of InGaAs/InAlAs electroabsorption modulator structures on (100) and (111) InP substrates, MAT SCI E B, 66(1-3), 1999, pp. 181-184
The MBE growth and properties of InGaAs/InAlAs heterostructures on vicinal
(111)B InP substrates have been investigated. Electroabsorption modulator p
in MQW heterostructures were grown on both (100) and vicinal (111)B InP sub
strates, pin diodes were processed and their photocurrent spectra at 300 K
were compared. The spectra of (100) structures exhibited many intense excit
onic transitions and applied reverse bias resulted to strong red shift of t
he absorption edge. The photocurrent spectra of similar (111) structures, h
owever, appeared rather featureless with less abrupt absorption edge. These
results on (111) are related to crystal disorder and quantum well variatio
ns resulting from InAlAs surface step-bunching and InGaAs, InAlAs compositi
onal modulations. (C) 1999 Elsevier Science S.A. All rights reserved.