Local structures of polar wurtzites Zn1-xMgxO studied by raman and 67Zn/25Mg NMR spectroscopies and by total neutron scattering

Journal Article · Tue Jan 01 00:00:00 EST 2008 · Physical Review. B, Condensed Matter and Materials Physics

OSTI ID:960598

Proffen, Thomas E ^[1]; Kim, Yiung- Il ^[2]; Cadars, Sylvian ^[2]; Shayib, Ramzy ^[2]; Feigerle, Charles S ^[3]; Chmelka, Bradley F ^[2]; Seshadri, Ram ^[2]

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1. Los Alamos National Laboratory
2. UCSB
3. UNIV OF TENNESSEE

Research in the area of polar semiconductor heterostructures has been growing rapidly, driven in large part by interest in two-dimensional electron gas (2DEG) systems. 2DEGs are known to form at heterojunction interfaces that bear polarization gradients. They can display extremely high electron mobilities, especially at low temperatures, owing to spatial confinement of carrier motions. Recent reports of 2DEG behaviors in Ga{sub 1-x}Al{sub x}N/GaN and Zn{sub 1-x}Mg{sub x}O/ZnO heterostructures have great significance for the development of quantum Hall devices and novel high-electron-mobility transistors (HEMTs). 2DEG structures are usually designed by interfacing a polar semiconductor with its less or more polar alloys in an epitaxial manner. Since the quality of the 2DEG depends critically on interface perfection, as well as the polarization gradient at the heterojunction, understanding compositional and structural details of the parent and alloy semiconductors is an important component in 2DEG design and fabrication. Zn{sub 1-x}Mg{sub x}O/ZnO is one of the most promising heterostructure types for studies of 2DEGs, due to the large polarization of ZnO, the relatively small lattice mismatch, and the large conduction band offsets in the Zn{sub 1-x}Mg{sub x}O/ZnO heterointerface. Although 2DEG formation in Zn{sub 1-x}Mg{sub x}O/ZnO heterostructures have been researched for some time, a clear understanding of the alloy structure of Zn{sub 1-x}Mg{sub x}O is currently lacking. Here, we conduct a detailed and more precise study of the local structure of Zn{sub 1-x}Mg{sub x}O alloys using Raman and solid-state nuclear magnetic resonance (NMR), in conjunction with neutron diffraction techniques.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC52-06NA25396
• OSTI ID: 960598
• Report Number(s): LA-UR-08-05431; LA-UR-08-5431; TRN: US201006%%1239
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Journal Name: Physical Review. B, Condensed Matter and Materials Physics; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALLOYS
CARRIERS
CONFINEMENT
DESIGN
ELECTRON GAS
ELECTRONS
FABRICATION
HETEROJUNCTIONS
INTERFACES
MAGNESIUM OXIDES
NEUTRON DIFFRACTION
NUCLEAR MAGNETIC RESONANCE
POLARIZATION
RAMAN SPECTROSCOPY
SCATTERING
SEMICONDUCTOR MATERIALS
SPECTROSCOPY
TEMPERATURE RANGE 0065-0273 K
TRANSISTORS
ZINC OXIDES