Study on GaN buffer leakage current in AlGaN/GaN high electron mobility transistor structures grown by ammonia-molecular beam epitaxy on 100-mm Si(111)

Journal Article · Sun Jun 28 04:00:00 EDT 2015 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4923035· OSTI ID:22490736

Ravikiran, L.; Ng, G. I. ^[1]; Munawar Basha, S.; Dharmarasu, N.; Agrawal, M.; Manoj kumar, C. M.; Arulkumaran, S. ^[2]

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1. NOVITAS-Nanoelectronics, Centre of Excellence, School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798 (Singapore)
2. Temasek Laboratories@NTU, Nanyang Technological University, Singapore 637553 (Singapore)

The effect of carbon doping on the structural and electrical properties of GaN buffer layer of AlGaN/GaN high electron mobility transistor (HEMT) structures has been studied. In the undoped HEMT structures, oxygen was identified as the dominant impurity using secondary ion mass spectroscopy and photoluminescence (PL) measurements. In addition, a notable parallel conduction channel was identified in the GaN buffer at the interface. The AlGaN/GaN HEMT structures with carbon doped GaN buffer using a CBr{sub 4} beam equivalent pressure of 1.86 × 10{sup −7} mTorr showed a reduction in the buffer leakage current by two orders of magnitude. Carbon doped GaN buffers also exhibited a slight increase in the crystalline tilt with some pits on the growth surface. PL and Raman measurements indicated only a partial compensation of donor states with carbon acceptors. However, AlGaN/GaN HEMT structures with carbon doped GaN buffer with 200 nm thick undoped GaN near the channel exhibited good 2DEG characteristics.

• OSTI ID: 22490736
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 24 Vol. 117; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
AMMONIA
BEAMS
BUFFERS
CARBON
DOPED MATERIALS
ELECTRICAL PROPERTIES
ELECTRON MOBILITY
GALLIUM NITRIDES
ION MICROPROBE ANALYSIS
LAYERS
LEAKAGE CURRENT
MASS SPECTROSCOPY
MOLECULAR BEAM EPITAXY
PHOTOLUMINESCENCE
TRANSISTORS