Journal of Vacuum Science & Technology B, Vol.19, No.6, 2119-2122, 2001
Metamorphic In0.52Al0.48As/In0.53Ga0.47As high electron mobility transistors on GaAs with InxGa1-xP graded buffer
A new metamorphic In0.52Al0.48As/In0.53Ga0.47As high electron mobility transistor (HEMT) structure was grown on a GaAs substrate with a InxGa1-xP graded buffer layer by solid-source molecular beam epitaxy. The In0.53Ga0.47As channel layer was grown on the InGaP buffer layer directly without an InAlAs buffer as in the conventional design. High-resolution x-ray diffraction reveals that the whole layer structure is nearly fully relaxed. Hall measurement showed that this new layer design exhibits higher electron mobility and carrier concentration as well as lower light sensitivity compared to the reference sample with the conventional design. The promising device performance demonstrates the potential of using this metamorphic HEMT device in high speed and high frequency applications.