【摘要】 用等离子体增强化学气相沉积(PECVD)的方法,以硅烷为源气体,在玻璃基片上沉积得到多孔的氧化硅薄膜。将反应过程中加在沉积区域的脉冲负偏压固定在-300V,当占空比从0.162增大到0.864时,薄膜样品的结构、形貌均不相同。拉曼光谱显示,位于480cm-1附近的峰在低占空比条件下存在,但是当占空比升高到0.702时该峰基本消失。位于560cm-1附近的峰则随着占空比的继续升高而增强,并出现蓝移,这说明薄膜样品中的非晶硅在占空比升高时消失,氧化硅所占比例不断增加,同时颗粒变小。扫描电镜照片也表明,组成多孔氧化硅薄膜的颗粒在占空比增大时变得细腻并且薄膜整体变得蓬松多孔。更多还原

【Abstract】 Porous silica films were prepared by plasma enhanced chemical vapor deposition(PECVD) system modulated by pulse negative bias voltage and silane as precursor gas.During duty cycle from 0.162 to 0.864 maintaining bias voltage at-300V,the Raman spectra and microstructure of the samples were investigated intensively.It was found that Raman peak appeared at 480cm-1 and 560cm-1 while the intensity of 480cm-1 peak weakened and that of 560cm-1 strengthened and blue shift with the increase of duty cycle.Raman spectra indicated that amorphous silicon vanished when duty cycle was at 0.702.The proportion of Si—O—Si bridge bond enhanced while the duty cycle increasing.The SEM revealed that the size of silica particles became smaller and silica films got more porous and fleecy.更多还原