Comparison of In0.33Al0.67As/In0.34Ga0.66As on GaAs metamorphic high electron mobility transistors grown by molecular beam epitaxy with normal and inverse step on linear graded buffer layers
Y. Cordier et al., Comparison of In0.33Al0.67As/In0.34Ga0.66As on GaAs metamorphic high electron mobility transistors grown by molecular beam epitaxy with normal and inverse step on linear graded buffer layers, J VAC SCI B, 18(5), 2000, pp. 2513-2517
Metamorphic high electron mobility transistors with 33% indium content have
been grown on GaAs by molecular beam epitaxy. Linear graded InAlAs buffer
layers were used to relax the mismatch strain between the InAlAs/InGaAs het
erostructure and the GaAs substrate. The thickness of the graded buffer is
shown to influence strain relaxation (tilt and residual strain), surface ro
ughness, and Hall mobility. Furthermore insertion of an inverse step at the
end of the grade by a finite reduction of the indium concentration reduces
the residual strain and provides similar surface roughness with improved H
all mobility in the InGaAs channel. (C) 2000 American Vacuum Society. [S073
4-211X(00)04405-X].