衬底温度对PLD法制备ZnO薄膜结构及发光特性的影响  

Effects of substrate temperature on structural and luminescent properties of ZnO thin films prepared by pulsed laser deposition

作　　者：赵杰[1] 胡礼中[2] 宫爱玲[1] 刘维峰[2] 

机构地区：[1]昆明理工大学物理系,云南昆明650093 [2]大连理工大学三束材料改性国家重点实验室及物理系,辽宁大连116024

出　　处：《功能材料》2008年第5期724-726,729,共4页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(60377005)

摘　　要：在60Pa的高氧压气氛中，用脉冲激光沉积法以Si（111）为衬底在不同温度下制备了ZnO薄膜。RHEED和XRD结果表明，所有样品都是c轴高度择优取向的多晶ZnO薄膜。随衬底温度的升高，ZnO薄膜（002）衍射峰的半高宽不断减小，从0．227～0．185°。对（002）衍射峰的2θ值分析表明，650℃下生长的ZnO薄膜几乎处于元应力的状态，而在较低或较高温度下生长的薄膜中都存在着一定程度的c轴压应力。室温PL谱测试说明在650℃生长的ZnO薄膜具有最强的紫外发射峰和最窄的UV峰半高宽（83meV）。在700℃得到的样品PL谱中，检测到一个位于3．25eV处的低能发射峰。经分析，该峰可能是来自于施主-受主对（DAP）的跃迁。ZnO thin films have been synthesized on Si（111） substrates with a high oxygen pressure of 60Pa by pulsed laser deposition （PLD）. The structural and luminescent properties of ZnO thin films as a function of substrate temperature were investigated by in situ reflection high-energy electron diffraction （RHEED）, X-ray diffraction （XRD）, and room-temperature photoluminescence （PL）. The results of RHEED and XRD show that all ZnO thin films have a polycrystalline structure and are c-axis preferred oriented. The full width at half maximum （FWHM） of （002） diffraction peak decreases from 0. 227-0. 185° as the substrate temperature increases from 600-700℃. The thin film grown at 650℃ is almost stress-free, while there is a plane-in tensile stress in other samples. PL measurement indicates that ZnO thin film prepared at 650℃ has the most intensive ultraviolet （UV） emission and the smallest UV peak FWHM of 83meV. A low-energy UV peak at 3.25eV is detected when the substrate temperature increases to 700℃, which possibly result from a donor-acceptor-pair （DAP） transition .

关 键 词：ZNO薄膜 反射式高能电子衍射 X射线衍射 光致发光 

分 类 号：O472[理学—半导体物理] O484[理学—物理]