MOVPE growth of high electron mobility AlGaN/GaN heterostructures

Book · Fri Nov 01 00:00:00 EST 1996

OSTI ID:394952

Redwing, J M; Flynn, J S; Tischler, M A ^[1]; Mitchel, W; Saxler, A ^[2]

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1. Advanced Technology Materials, Inc., Danbury, CT (United States)
2. Electronic and Optical materials Branch, Wright-Patterson AFB, OH (United States)

The authors have fabricated Al{sub x}Ga{sub 1{minus}x}N/GaN heterostructures with high two-dimensional electron gas (2DEG) mobilities and high sheet carrier densities by metalorganic vapor phase epitaxy (MOVPE). The 2DEG sheet density and mobility exhibit a compositional dependence on the Al fraction of the electron donor layer. The highest mobility (5,750 cm{sup 2}/Vs at 16K) was measured in a sample with x = 0.15 that had a sheet carrier density of 8.5 {times} 10{sup 12} cm{sup {minus}2}. The undoped Al{sub x}Ga{sub 1{minus}x}N layers have low background carrier concentrations and can be intentionally doped n-type using SiH{sub 4}. The effect of intentional n-type doping of the Al{sub x}Ga{sub 1{minus}x}N donor layer on the electrical properties of the 2DEG was studied in structures that included an undoped Al{sub x}Ga{sub 1{minus}x}N spacer layer of varying thickness. Higher 2DEG mobilities were obtained when a 100{angstrom} thick undoped layer was included in the structure due to spatial separation of the 2DEG from ionized impurities in the doped Al{sub x}Ga{sub 1{minus}x}N. These initial results demonstrate that the electrical properties of Al{sub x}Ga{sub 1{minus}x}N/GaN heterostructures can be controlled by intentional doping and appropriate layer design.

• OSTI ID: 394952
• Report Number(s): CONF-951155-; ISBN 1-55899-298-7; TRN: IM9648%%29
• Resource Relation: Conference: Fall meeting of the Materials Research Society (MRS), Boston, MA (United States), 27 Nov - 1 Dec 1995; Other Information: PBD: 1996; Related Information: Is Part Of Gallium nitride and related materials; Ponce, F.A. [ed.] [Xerox Palo Alto Research Center, CA (United States)]; Dupuis, R.D. [ed.] [Univ. of Texas, Austin, TX (United States)]; Nakamura, S. [ed.] [Nichia Chemical Industries, Tokushima (Japan)]; Edmond, J.A. [ed.] [Cree Research, Inc., Durham, NC (United States)]; PB: 993 p.; Materials Research Society symposium proceedings, Volume 395
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
42 ENGINEERING NOT INCLUDED IN OTHER CATEGORIES
COMPOSITE MATERIALS
CHEMICAL VAPOR DEPOSITION
CRYSTAL STRUCTURE
ELECTRICAL PROPERTIES
ALUMINIUM NITRIDES
GALLIUM NITRIDES
ELECTRONIC EQUIPMENT
SEMICONDUCTOR MATERIALS
SAPPHIRE
ORGANOMETALLIC COMPOUNDS
AMMONIA
HYDROGEN
DOPED MATERIALS
SILICON
X-RAY DIFFRACTION
HALL EFFECT
CARRIER DENSITY
INTERFACES
ELECTRON MOBILITY
ELECTRIC CONDUCTIVITY
EXPERIMENTAL DATA