热丝化学气相沉积法低温制备纳米晶态碳化硅薄膜

采用热丝化学气相沉积(HFCVD)技术以甲烷(CH4)和硅烷(SiH4)作为源反应气体在Si(111)衬底上合成了纳米晶态SiC薄膜。通过X射线衍射(XRD)、扫描电镜(SEM)、高分辨透射电镜(HRTEM)以及光致发光(PL)检测技术对薄膜的晶体结构、表面形貌和PL特性进行了分析和表征。结果表明，在较低的衬底温度下所沉积的薄膜是由镶嵌于非晶SiC网络中的晶态纳米SiC构成。纳米晶粒平均尺寸约为6nm。室温下用HeCr激光激发样品，观到薄膜发出波长位于400～550nm范围内可见光辐射。

Preparation of Nanocrystalline SiC Films by Hot Filament Chemical Vapor Deposition at Low Temperature

Nanocrystalline SiC films have been synthesized on Si(111) substrate by hot filament chemical vapor deposition(HFCVD) technique with CH4 and SiH4 as reaction gases.X-ray diffraction(XRD),scanning electron microscopy(SEM),high-resolution transmission electron microscopy(HRTEM) and photoluminescence(PL) spectroscopy are used to investigate the structure,morphology and PL of the films respectively.Results from these techniques show that the films deposited at relatively low substrate temperature contain SiC nanocrystalites,with an average dimension of about 6 nm,embedded in an amorphous SiC matrix.The visible-light emitting in the wavelength range between 400 nm and 550 nm has been observed from the nanocrystalline films excited by a HeCr laser at room temperature.