Y. Takano et al., Residual strain and threading dislocation density in InGaAs layers grown on Si substrates by metalorganic vapor-phase epitaxy, APPL PHYS L, 78(1), 2001, pp. 93-95
InGaAs layers with In contents between 0.007 and 0.055 have been grown on G
aAs epilayers on Si substrates by low-pressure metalorganic vapor-phase epi
taxy. The threading dislocation density of the order of 10(5) cm(-2) in the
InGaAs layer was achieved by insertion of an InGaAs strained layer combine
d with thermal cycle annealing. Photoluminescence measurement for layers co
nfirmed that the residual strain was lower in InxGa1-xAs layers with x grea
ter than or equal to0.038 than that in GaAs. It is suggested that the tensi
le strain due to the difference in the thermal expansion coefficient betwee
n InGaAs and Si materials was compensated by the compressive strain partly
due to the slow strain relaxation by work hardening in InGaAs layers grown
on GaAs layers or due to the incomplete strain relaxation in InGaAs layers
at the small thickness of 1 mum. (C) 2001 American Institute of Physics.