Intense wide-band photoluminescence(PL)with high stability to ultraviolet(UV)light irradiation has been observed in a wide temperature range from a polycrystalline SiC sintered from graphite and melt Si at high temper...Intense wide-band photoluminescence(PL)with high stability to ultraviolet(UV)light irradiation has been observed in a wide temperature range from a polycrystalline SiC sintered from graphite and melt Si at high temperature over 1500°C.X-ray diffraction results showed that the sintered material consists of mainly cubic and 6H-SiC crystallites oriented randomly and a smallamount of graphite with(002)preferential orientation.PLspectra of the samples were measured under excitation of the incident UV light beam from an He-Cd laser(325 nm,l0mW)in the temperature range from 10 to 300 K.The PL spectra were found to be a single wide-band centered around 2.2 eV at room temperature and to be divided into a much more intensive blue band and a lessintensive red band at low temperature.The low temperature PL bands consist of several luminescence peaks that change in intensities relatively with variation of temperature.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.69876030.
文摘Intense wide-band photoluminescence(PL)with high stability to ultraviolet(UV)light irradiation has been observed in a wide temperature range from a polycrystalline SiC sintered from graphite and melt Si at high temperature over 1500°C.X-ray diffraction results showed that the sintered material consists of mainly cubic and 6H-SiC crystallites oriented randomly and a smallamount of graphite with(002)preferential orientation.PLspectra of the samples were measured under excitation of the incident UV light beam from an He-Cd laser(325 nm,l0mW)in the temperature range from 10 to 300 K.The PL spectra were found to be a single wide-band centered around 2.2 eV at room temperature and to be divided into a much more intensive blue band and a lessintensive red band at low temperature.The low temperature PL bands consist of several luminescence peaks that change in intensities relatively with variation of temperature.
