80keV N离子注入对ZnO薄膜结构的影响

Effects of 80 keV N-ion Implantation on Structures of ZnO Films

室温下用80keVN离子注入ZnO薄膜样品,注量分别为5.01014,5.01015和5.01016ions/cm2,然后用X射线衍射和透射电镜技术对样品的结构特性进行了表征。实验结果表明,由高度(002)择优取向的致密柱状晶构成的薄膜中,注入5.0×1015ions/cm2时,观测到缺陷生成和局域无序化现象,但薄膜总体结构仍保持柱状晶和(002)择优取向;随着注量的增大,晶格常数c和压应力呈增大趋势。对注入N离子对ZnO薄膜结构特性的影响机理进行了简单的讨论。

ZnO thin films were implanted at the room temperature by 80 keV N-ions to 5.0×10^14,5.0×10^15 or 5.0×10^16 ions/cm^2,the structural characteristics of the samples were investigated using X-ray diffraction（XRD） spectrometer and transmission electron microscopy（TEM）.It was found that the un-implanted ZnO films are constituted of columnar crystals which are very compact and of preferred c-axis orientation.After N-ion implantation,the crystal lattice constant and the biaxial compressive stress increased with the increasing of the N-implantation dose.In the 5.0×10^16 N-ions/cm^2 implanted ZnO sample,a new XRD peak due to defects or N-dopants appeared.Moreover,defects and localized disordering in the 5.0×10^15 N-ions/cm^2 implanted ZnO films have been observed under high resolution TEM measurement.However,N-ion implantation could not change significantly the crystal structure of the ZnO films.Possible mechanism of the structural modification of ZnO films by N-ion implantation was briefly discussed.