氧化鋅奈米線與橫向磊晶成長的氮化鎵之拉曼光譜研究

Optical Investigation of ZnO Nanorods and GaN Growth by Epitaxial Lateral Overgrowth

姚秋蓮

指導教授 ： 劉祥麟

國立臺灣師範大學/理學院/物理學系在職進修碩士班/碩士(2004年)

摘要

無資料

關鍵字

氧化鋅 ； 氮化鎵 ； 拉曼光譜

並列摘要

We present the results of the Raman-scattering measurements of ZnO nanorods by self-catalyzed vapor-liquid-solid（VLS）process and GaN microstructures grown by epitaxial lateral overgrowth（ELO）using hydride vapor phase epitaxy（HVPE）.
The Raman spectrum of the ZnO nanorods exhibit three sharp phonon peaks at ~ 101,379, and 438 cm-1, corresponding to symmetries E2(low), A1(TO), and E2(high), respectively . It reveals a low concentration of oxygen vacancies in these ZnO nanorods and their high optical quality.
By varying the carrier gas composition (hydrogen versus nitrogen), the growth mode of GaN microstructure can be modified during deposition. The Raman-active E2 (high) phonon is found to gauge the strain distributions of the sample, which gives evidence of the biaxial strain of －0.81 GPa, －0.51GPa, and －0.38 GPa in hydrogen, 1:1 mixed hydrogen/nitrogen, and nitrogen content. Moreover, the peak shift and the broadening of the linewidths as well as asymmetric shape observed in A1(LO) phonon agree with those calculated on the basis of the LO phonon-plasmon model, suggesting a low carrier density of 1 × 1017 cm-3 in hydrogen and 1:1 mixed hydrogen/nitrogen content.