Cheng Hsin-Ming, Hsu Hsu-Cheng, Tseng Yung-Kuan, Lin Li-Jiaun, Hsieh Wen-Feng
Department of Photonics and Institute of Electro-Optical Engineering, National Chiao Tung University, 1001 Tahsueh Road, Hsinchu 30050, Taiwan.
J Phys Chem B. 2005 May 12;109(18):8749-54. doi: 10.1021/jp0442908.
Optical phonon confinement and efficient UV emission of ZnO nanowires were investigated in use of resonant Raman scattering (RRS) and photoluminescence (PL). The high-quality ZnO nanowires with diameters of 80-100 nm and lengths of several micrometers were epitaxially grown through a simple low-pressure vapor-phase deposition method at temperature 550 degrees C on the precoated GaN(0001) buffer layer. The increasing intensity ratio of n-order longitudinal optical (LO) phonon (A(1)(nLO)/E(1)(nLO)) with increasing scattering order in RRS reveals the phonon quantum confinement as shrinking the diameter of ZnO nanowires. The exciton-related recombination near the band-edge transition dominate the UV emissions at room temperature as well as at low temperature that exhibits almost no other nonstoichiometric defects in the ZnO nanowires.
利用共振拉曼散射（RRS）和光致发光（PL）研究了ZnO纳米线的光学声子限制和高效紫外发射。通过简单的低压气相沉积法，在550℃下于预涂覆的GaN(0001)缓冲层上外延生长出直径为80 - 100nm、长度为几微米的高质量ZnO纳米线。RRS中n阶纵向光学（LO）声子的强度比（A(1)(nLO)/E(1)(nLO)）随散射阶数增加而增大，这揭示了随着ZnO纳米线直径缩小的声子量子限制。在室温以及低温下，带边跃迁附近的激子相关复合主导了紫外发射，这表明ZnO纳米线中几乎不存在其他非化学计量缺陷。
