Growth of AlGaN/GaN heterojunction field effect transistors on semi-insulating GaN using an AlGaN interlayer

Journal Article · Mon Mar 16 00:00:00 EDT 2009 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.3103210· OSTI ID:21176046

Chen, Z; Denbaars, S P ^[1]; Pei, Y; Newman, S; Chu, R; Brown, D; Keller, S; Mishra, U K ^[1]; Chung, R; Nakamura, S ^[2]

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1. Electrical and Computer Engineering, University of California, Santa Barbara, California 93106 (United States)
2. Materials Department, University of California, Santa Barbara, California 93106 (United States)

Semi-insulating (SI) GaN layers were grown on 4H-SiC substrates by inserting an AlGaN layer between the AlN buffer and the GaN layer. Secondary ion mass spectroscopy measurements showed that the AlGaN layer prevented Si from diffusing from the substrate into the GaN layer. X-ray diffraction and atomic force microscopy analyses showed that an optimized AlGaN interlayer does not degrade the crystal quality or surface morphology of the SI GaN. The room temperature mobility of an AlGaN/GaN heterostructure using this SI GaN was 2200 cm{sup 2}/V s. High electron mobility transistors (HEMTs) with 0.65 {mu}m long gates were also fabricated on these SI GaN buffers. A power density of 19.0 W/mm with a power added efficiency of 48% was demonstrated at 10 GHz at a drain bias of 78 V. These HEMTs also exhibited sharp pinch off, low leakage, and negligible dispersion.

• OSTI ID: 21176046
• Journal Information: Applied Physics Letters, Vol. 94, Issue 11; Other Information: DOI: 10.1063/1.3103210; (c) 2009 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM NITRIDES
ATOMIC FORCE MICROSCOPY
CARRIER MOBILITY
CHEMICAL VAPOR DEPOSITION
CRYSTAL GROWTH
ELECTRON MOBILITY
FIELD EFFECT TRANSISTORS
GALLIUM NITRIDES
GHZ RANGE 01-100
HETEROJUNCTIONS
ION MICROPROBE ANALYSIS
LAYERS
MASS SPECTRA
MASS SPECTROSCOPY
MORPHOLOGY
POWER DENSITY
SEMICONDUCTOR MATERIALS
SUBSTRATES
TEMPERATURE RANGE 0273-0400 K
X-RAY DIFFRACTION