溶胶凝胶软石印法制备Zn_2SiO_4∶Mn图案化薄膜及其发光性能的研究

Patterning and Luminescence Properties of Zn_2SiO_4∶Mn Films by Sol-gel Soft Lithography

采用溶胶 凝胶法制备了Zn2SiO4∶Mn薄膜并结合毛细管微模板技术实现了薄膜的图案化,利用X射线衍射(XRD),原子力显微镜,光学显微镜,发光光谱等手段对Zn2SiO4∶Mn的结晶过程、发光性质进行了研究。XRD结果表明,溶胶 凝胶法合成的样品在800℃时已开始结晶,在1000℃时可得到纯相的Zn2SiO4∶Mn,这比传统的固相法的烧结温度低150℃。Zn2SiO4∶Mn薄膜的激发光谱在220nm和280nm之间有一个强的吸收峰,峰值位于248nm,发射光谱的最大值位于522nm,为绿光发射。从原子力显微镜照片可知组成薄膜的粒子比较均匀,其平均直径为220nm。我们获得了四种图案化宽度,分别是5,10,20,50μm。光学显微镜的结果表明,图案薄膜烧结后相对于烧结前有10%～20%的收缩。

Luminescent materials based on Zn2SiO4∶Mn are used as the green compon ent of projection television and ppc copy machines due to its high luminesc ence efficiency. The solgel technology, characterized by simple procedures and faci l ities, is very suitable for deposition of thin amorphous and crystalline films, which have found applications in many fields. Future integrated circuits will re q uire reliable technique for fabricating nanometerscale devices. Optical lithog r aphy or photolithography, which has been and will be the mainstay of lithography for the near future, is expected to be limited to 100nm resolution. In this p ap er, Mn2+doped Zn2SiO4 phosphor films and their patterning were fab ricated on si licon and quartz glass substrates by solgel process (dipcoating) combined wi th a soft lithography. The resulted film samples were characterized by Xray diff r action (XRD), atomic force microscope (AFM), optical microscope and photolumines cence excitation and emission spectra. The results of XRD reveal that these film s remain amorphous below 700℃, begin to crystallize at 800℃ and crystallize co mpletely around 1 000℃. The grain structure of the film can be seen clearly fro m AFM micrographs, where particles with average size of 220nm can be resolved. Th e films show a strong green emission with a maximum at 522nm and corresponding excitation band was ranging from 220 to 280nm with a maximum at 248nm. Four kind s of patterning structures with film line widths of 5, 10, 20 and 50μm have bee n obtained by micromolding in capillaries soft lithography technique. The optica l microscopy micrographs show that the film bands had a 10%～20% shrinkage after firing.