Lifetime of nonequilibrium carriers in AlGaN epilayers with high Al molar fraction

Author

Mickevicius, J. ; Aleksiejunas, R. ; Shur, M.S. ; Zhang, J.P. ; Fareed, Q. ; Gaska, R. ; Tamulaitis, G.

Author_Institution

Dept. of Electr. & Comput. Eng., Rensselaer Polytech. Inst., Troy, NY, USA

fYear

2004

fDate

4-6 Aug. 2004

Firstpage

72

Lastpage

77

Abstract

AlGaN epilayers with different aluminum content have been studied by photoluminescence (PL) and light-induced transient grating (LITG) techniques. The epilayers were grown by conventional metal organic chemical vapor deposition (MOCVD) and by migration enhanced MOCVD (MEMOCVDTM). The carrier lifetime and PL intensity in epilayers containing the same amount of aluminum are shown to be inversely proportional to the dislocation density, which was determined using etch pit technique. The carrier diffusion length is shown to be close to the average distance between two first-neighbor dislocations. Enhancement of the lifetime and PL intensity in epilayers grown on sapphire by MEMOCVD™ is demonstrated.

Keywords

III-V semiconductors; MOCVD; aluminium compounds; carrier lifetime; gallium compounds; sapphire; vapour phase epitaxial growth; wide band gap semiconductors; Al₂O₃; AlGaN; AlGaN epilayers; aluminum content; carrier diffusion length; dislocation density; etch pit technique; first-neighbor dislocations; high Al molar fraction; light-induced transient grating; metal organic chemical vapor deposition; migration enhanced MOCVD; nonequilibrium carrier lifetime; photoluminescence; sapphire; Aluminum gallium nitride; Chemical vapor deposition; Etching; Gratings; Light emitting diodes; MOCVD; Metallic superlattices; Optical pulses; Organic chemicals; Photoluminescence;

fLanguage

English

Publisher

ieee

Conference_Titel

High Performance Devices, 2004. Proceedings. IEEE Lester Eastman Conference on

Print_ISBN

981-256-196-X

Type

conf

DOI

10.1109/LECHPD.2004.1549674

Filename

1549674