合成了适于半绝缘碳化硅单晶生长的高纯度SiC粉料。实验发现,不同的硅粉形状、粒度以及合成温度、时间都对合成产物的形貌、组成和产率有影响。合成产物的形貌通过扫描电子显微镜(SEM)观察,结构通过粉末衍射法(XRD)测定。结果表明,合成产率与Si粉的表面积有十分重要的关系,表面积越大,合成产率越高。合成温度和时间则决定了合成产物中α-SiC和β—SiC的比例。辉光放电质谱(GDMS)测量了合成产物的杂质含量,表明合成产物符合半绝缘SiC单晶的生长要求。
High purity silicon carbide (SIC) powder for semi-insulating SiC single crystal growth was synthesized. The results show that the size of Si powder, the temperature and time of the synthesis process effect the composition of the products. The phase composition and morphology of the products were investigated by X-ray diffraction and scanning electron microscopy (SEM). The results show that the composition of SiC powder depends on the surface area of Si powder. The ratio of α-SiC and β-SIC depends on the synthesis temperature and time. Glow discharge mass spectroscopy (GDMS) was used to evaluate the impurity concentration.