全氢聚硅氮烷制备SiO_x涂层及其性能研究

Preparation and Characterization of SiO_x Coating from Perhydropolysilazane

以全氢聚硅氮烷(PHPS)为先驱体,采用氨水转化法在Si片基底上制备了SiOx涂层。利用扫描电镜(SEM)、紫外光谱仪、椭圆偏振仪、纳米压痕仪等对涂层的形貌、厚度、光学性能和力学性能进行了表征。结果表明在氨水气氛中,不同处理时间获得的涂层对可见光的透过率均大于95%,具有良好的透明性;随着处理时间的增加,涂层的折光指数变小,硬度和模量增大;处理4h后,PHPS完全转化为SiOx,涂层厚度约为280nm,610nm波长处折光指数约为1.41,硬度和模量分别达到3GPa和60GPa;继续延长处理时间,涂层的折光指数、硬度和模量基本不变。

Perhydropolysilazane (PHPS) was used as precursor for preparing SiO x coatings on Si(100) substrate at room temperature. The PHPS-to-silica conversion was achieved by exposing the spin-on coatings to the vapor from aqueous ammonia with a concentration of 5mol/L. The conversion of the coating and corresponding properties at different treating time were studied. The results suggest that transparency of the coating obtained for various periods of time in the vapor of aqueous ammonia exceeds 95%, indicating that the coatings prepared with PHPS is highly transparent. As the exposer time increases, the refractive index decreases from 1.58 to 1.41, and the surface hardness and elastic modulus of the coatings increase to 3 GPa and 60 GPa, respectively. The coatings exposed to the vapor of aqueous ammonia for 4h are identical to silica glass and the thickness of the obtained coatings is about 280 nm.