固相烧结多孔碳化硅的光致发光及电阻率

Photoluminescence and Electrical Resistivity of Solid-Sintered Porous SiC

碳化硅粉末经压制成型后,在高温常压下固相烧结制成多孔碳化硅样品。用紫外激光对样品激发,样品的光致发光谱在低温下在2.02eV位置出现一发光主峰,在2.13eV位置出现一微弱肩峰;在室温下发光峰位置有所蓝移。样品的电阻率随着烧结温度的上升而上升,随着成型压力的升高而降低。发光来自缺陷态。

Sample of porous SiC polycrystals are prepared by solid sintering process under high temperature and normal pressure using moulding SiC powder.Upon the excitation of ultraviolet light (UV), a photoluminescence peak and a weaker shoulder peak are found at 2.02 eV and 2.13 eV respectively at low temperature. The luminescent peak position has some blueshift occurence at the room temperature. The electrical resistivity rises as the sintering temperature rises, and falls as the moulding pressure rises. A defective model is suggested to explain the UVinduced PL variation in porous SiC.