Vapor phase synthesis of fluorescent gallium nitride powders

Citation
K. Hara et al., Vapor phase synthesis of fluorescent gallium nitride powders, JPN J A P 2, 40(3B), 2001, pp. L242-L244
Citations number
15
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Volume
40
Issue
3B
Year of publication
2001
Pages
L242 - L244
Database
ISI
SICI code
0021-4922(20010315)40:3B<L242:VPSOFG>2.0.ZU;2-A
Abstract
GaN crystalline powders have been synthesized by the reaction of a Ga vapor with ammonia at the reaction temperatures (T-t) of 900-1100 degreesC under the atmospheric pressure. The size of the crystalline particles ranges fro m 0.2 to 2 gm. The structural and the luminescent properties depend strongl y on T-r. For T-r greater than or equal to 1050 degreesC, the powders consi st primarily of hexagonal GaN particles, whereas those synthesized at T-r l ess than or equal to 1000 degreesC contain cubic GaN particles. Photolumine scence (PL) spectra are dominated by band-edge emissions. For the powders s ynthesized at higher T-r, reduction in the PL intensity between 24 and 293 K indicates excellent luminescent quality. Thermal quenching is relatively significant for the powders synthesized at lower T-r. This is presumably du e to enhanced nonradiative recombination at the surface because of their sm all particle size.