摘要
在LP MOCVD中 ,我们利用Zn(C2 H5) 2 作Zn源 ,CO2 作氧源 ,在 (0 0 0 2 )蓝宝石衬底上成功制备出c轴取向高度一致的ZnO薄膜 ,并对其进行 5 0 0℃~ 80 0℃四个不同温度的退火。利用XRD、吸收谱、光致发光谱和AFM等手段研究了退火对ZnO晶体质量和光学性质的影响。退火后 ,(0 0 0 2 )ZnO的XRD衍射峰强度显著增强 ,c轴晶格常数变小 ,同时 (0 0 0 2 )ZnOX射红衍射峰半高宽不断减小表明晶粒逐渐增大 ,这与AFM观察结果较一致。由透射谱拟合得到的光学带隙退火后变小 ,PL谱的带边发射则加强 ,并出现红移 ,蓝带发光被有效抑制 ,表明ZnO薄膜的质量得到提高。
High-quality c-axis oriented ZnO films have been successfully deposited on (0002) sapphire substrate by LP-MOCVD technique, and annealed at various temperatures from 500℃ to 800℃. The effect of annealing on the optical and structural properties has been investigated by means of X-ray diffraction (XRD), transmittance and photoluminescence(PL) measurements, and atomic force microscope (AFM). Annealing at high temperature is found to enhance the intensity of the (0002) ZnO XRD peak and decrease the c-axis oriented lattice constant. Meanwhile, the smaller FWHM of (0002)ZnO peak is indicative the integration of the grains, well supported by the measurement of AFM. As the annealing temperature increased, the edge emission band became intense has a slinght red shift, while the blue band emissions is weakened, indicative of the decreasing of native defects and the improvement of the crystallinity.
出处
《高技术通讯》
EI
CAS
CSCD
2002年第12期45-48,共4页
Chinese High Technology Letters
基金
国家 973计划 (G0 0 1CB30 95 )资助项目。