氮分压对氮化铜薄膜结构及光学带隙的影响

在不同的氮分压r(r=N₂/［N₂+Ar］)和射频功率P下，使用反应射频磁控溅射法，在玻璃基片上制备了氮化铜薄膜样品.用台阶仪测得了薄膜的厚度，用原子力显微镜、X射线衍射仪、紫外-可见光谱仪对薄膜的表面形貌、结构及光学性质进行了表征分析.结果表明，薄膜的沉积速率随P和r的增加而增大.薄膜表面致密均匀，晶粒尺寸为30nm左右.随着r的增加，薄膜颗粒增大，且薄膜由(111)晶面转向(100)晶面择优生长.薄膜的光学带隙E_g在1.47—1.82eV之间，随r的增加而增大. 关键词： 氮化铜薄膜 反应射频磁控溅射 晶体结构 光学带隙

Effect of nitrogen pressure on structure and optical band gap of copper nitride thin films

Copper nitride(Cu_3N)thin films were deposited on glass substrates by reactive radio frequency magnetron sputtering under different radio frequency power(P)and nitrogen partial pressure r(r=N_2/N_2 Ar]).The thickness,crystalline structure and surface morphology of films were characterized by profilometer,X-ray diffraction(XRD)and atomic force microscopy(AFM),respectively.The optical transmission spectrum was obtained by an ultraviolet-visible(UV-VIS)spectrophotometer and the optical band gap(E_g)was calculated.The results suggest that the films' deposition rate increases with P and r.The surface of the films reveals a compact structure,and the grain size of Cu_3N is about 30nm.Meanwhile,with increasing r,the grain size and optical band gap of Cu_3N increase,of which E_g ranges from 1.47 to 1.82eV,and the films' growth prefers the(111)direction at low r and the(100)direction at high r.