| 초록 |
Silicon nitride ceramics (Si3N4) which is one of the best structural ceramic materials has been spotlighted in the field of electronic substrate materials. It has excellent properties like outstanding mechanical properties, high chemical stability, good thermal shock resistance, and so on. For further intensive application as a superb ceramic substrate, Si3N4 ceramics must have the enhanced mechanical strength and thermal conductivity. In this study, the Si3N4 was pressureless sintered with various rare-earth oxide additives and its mechanical and thermal properties were investigated. The sintering additive systems consisted of MgO as a basic fixed additive, Y2O3, Yb2O3, La2O3 as rare-earth oxide additives, and SiO2 as a non-rare-earth oxide additive, whose properties were evaluated. In order to investigate the factors affecting the thermal conductivity, the distribution of the secondary phase in grain boundary were investigated. Furthermore, the analysis of thermal conductivity was approached by using Raman spectroscopy instead of the conventional laser flash method. |
