The critical role of growth temperature on the structural and electrical properties of AlGaN/GaN high electron mobility transistor heterostructures grown on Si(111)
- CRHEA-CNRS, rue Bernard Gregory, Parc de Sophia Antipolis, 06560 Valbonne (France)
This work is dedicated to the study of the growth by ammonia source molecular beam epitaxy of Al{sub x}Ga{sub 1-x}N/GaN high electron mobility transistors on (111) oriented silicon substrates. The effect of growth conditions on the structural and electrical properties of the heterostructures was investigated. It is shown that even a slight variation in the growth temperature of the thick GaN buffer on AlN/GaN stress mitigating layers has a drastic influence on these properties via a counterintuitive effect on the dislocation density. Both in situ curvature measurements and ex situ transmission electron microscopy and x-ray diffraction experiments indicate that the relaxation rate of the lattice mismatch stress increases with the growth temperature but finally results in a higher dislocations density. Furthermore, a general trend appears between the final wafer curvature at room temperature and the threading dislocation density. Finally, the influence of the dislocation density on the GaN buffer insulating properties and the two-dimensional electron gas transport properties at the Al{sub x}Ga{sub 1-x}N/GaN interface is discussed.
- OSTI ID:
- 21186013
- Journal Information:
- Journal of Applied Physics, Vol. 105, Issue 3; Other Information: DOI: 10.1063/1.3063698; (c) 2009 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
Similar Records
Influence of strain induced by AlN nucleation layer on the electrical properties of AlGaN/GaN heterostructures on Si(111) substrate
The role of AlGaN buffers and channel thickness in the electronic transport properties of Al{sub x}In{sub 1–x}N/AlN/GaN heterostructures
Related Subjects
ALUMINIUM NITRIDES
AMMONIA
CRYSTAL GROWTH
DISLOCATIONS
ELECTRICAL PROPERTIES
ELECTRON GAS
ELECTRON MOBILITY
GALLIUM NITRIDES
MOLECULAR BEAM EPITAXY
SEMICONDUCTOR MATERIALS
SILICON
SUBSTRATES
TEMPERATURE RANGE 0273-0400 K
TRANSISTORS
TRANSMISSION ELECTRON MICROSCOPY
TWO-DIMENSIONAL CALCULATIONS
X-RAY DIFFRACTION