Structural and optical properties of Cr-doped semi-insulating GaN epilayers
- 1. Key Laboratory of Acoustic and Photonic Materials and Devices of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan 430072 (China)
- 2. Leibniz-Institut fuer Oberflaechenmodifizierung, D-04318 Leipzig (Germany)
Description
The properties of Cr-doped GaN epilayers grown by rf-plasma-assisted molecular beam epitaxy were studied. The deep acceptor nature of Cr was used to grow semi-insulating GaN epilayers on sapphire substrates for electronic device applications. The room-temperature (RT) sheet resistivity of the epilayers reached 1010 Ω/square. The activation energy of dark conductivity was about 0.48 eV. Step-graded AlxGa1-xN/GaN (x=0.3-0.2) superlattices (SLs) were designed to filter dislocations. Transmission electron microscopy images showed that the SLs can dramatically reduce dislocation density. Al0.35Ga0.65N/GaN heterostructure grown on Cr-doped semi-insulating GaN epilayer exhibited a RT mobility of 960 cm2/V s and sheet carrier density of 2.1x1013 cm-2
Additional details
Identifiers
- DOI
- 10.1063/1.2988000;
Publishing Information
- Journal Title
- Applied Physics Letters
- Journal Volume
- 93
- Journal Issue
- 11
- Journal Page Range
- p. 113507-113507.3
- ISSN
- 0003-6951
- CODEN
- APPLAB
INIS
- Country of Publication
- United States
- Country of Input or Organization
- International Atomic Energy Agency (IAEA)
- INIS RN
- 40050968
- Subject category
- S36: MATERIALS SCIENCE;
- Descriptors DEI
- ACTIVATION ENERGY; ALUMINIUM NITRIDES; CARRIER DENSITY; CARRIER MOBILITY; CHROMIUM; CRYSTAL GROWTH; DISLOCATIONS; DOPED MATERIALS; ELECTRIC CONDUCTIVITY; ELECTRONIC EQUIPMENT; GALLIUM NITRIDES; HETEROJUNCTIONS; MOLECULAR BEAM EPITAXY; OPTICAL PROPERTIES; SAPPHIRE; SEMICONDUCTOR MATERIALS; SUBSTRATES; SUPERLATTICES; TEMPERATURE RANGE 0273-0400 K; TRANSMISSION ELECTRON MICROSCOPY
- Descriptors DEC
- ALUMINIUM COMPOUNDS; CORUNDUM; CRYSTAL DEFECTS; CRYSTAL GROWTH METHODS; CRYSTAL STRUCTURE; ELECTRICAL PROPERTIES; ELECTRON MICROSCOPY; ELEMENTS; ENERGY; EPITAXY; EQUIPMENT; GALLIUM COMPOUNDS; LINE DEFECTS; MATERIALS; METALS; MICROSCOPY; MINERALS; MOBILITY; NITRIDES; NITROGEN COMPOUNDS; OXIDE MINERALS; PHYSICAL PROPERTIES; PNICTIDES; SEMICONDUCTOR JUNCTIONS; TEMPERATURE RANGE; TRANSITION ELEMENTS
Optional Information
- Notes
- (c) 2008 American Institute of Physics