Design of glass–ceramic complex microstructure with using onset point of crystallization in differential thermal analysis

Two types of frits with different compositions were used to develop a high strength substrate in electronic packaging using a low temperature co-fired ceramic process. In order to reveal the crystallization stage during heating to approximately 900 °C, a glass–ceramic consisting of the two types of frits, which had been crystallized to diopside and anorthite after firing, was tested at different mixing ratios of the frits. The exothermal peaks deconvoluted by a Gauss function in the differential thermal analysis curves were used to determine the onset point of crystallization of diopside or anorthite. The onset points of crystallization were affected by the mixing ratio of the frits, and the microstructure of the glass–ceramic depended on the onset point of crystallization. It was found that when multicrystalline phases appear in the microstructure, the resulting complex microstructure could be predicted from the onset point of crystallization obtained by differential thermal analysis.