Photoluminescence of Polycrystalline SiC Sintered from Graphite and Si Melt

• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2000,（10）
• 所属期刊栏目: Condensed matter: structure, mechanical
• 页码范围: 770-772
• 页数: 3页
• 语种: 英文

摘要

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.