不同先驱体溶胶-凝胶法制备的硫化锗玻璃薄膜

PREPARATION OF GERMANIUM SULFIDE GLASS FILMS BY SOL-GEL METHOD WITH DIFFERENT PRECURSORS

分别使用氯化锗和正锗酸乙脂为溶胶凝胶先驱体 ,用 2种不同的操作步骤制备溶胶 ,采用旋转涂膜技术在单晶硅片和玻璃基片上制备了硫化锗薄膜。对所获得的样品进行了X射线衍射、远红外和Raman光谱测试 ,并用扫描电镜观察薄膜形貌。结果表明 :采用不同先驱体制备的溶胶凝胶硫化锗玻璃薄膜其玻璃结构具有差异 ,并导致薄膜折射率的不同 ;由GeCl4 所得玻璃薄膜为富锗相 ,其折射率约为 2 .8;而由Ge(OC2 H5) 4所得玻璃薄膜为富硫相 ,折射率约为 2 .2。

Germanium sulfide films on silicon wafers or glass substrates were prepared by two different sol-gel procedures, using germanium chloride and germanium ethoxide as the precursors and the spin-coating technique. The obtained samples were measured by means of X-ray diffraction, far-IR and Raman spectra and the morphology of the films were investigated by scanning electron microscopy (SEM). The results indicate that different refractive indexes of germanium sulfide glass films prepared by different precursor are obtained due to the differences in glass structure. The Ge-S glass films prepared from GeCl4 are of Ge-rich with refractive index of ca. 2.8 and the Ge-S glass films from Ge(OC2H5)4 are of S-rich with refractive index of ca. 2.2.