To meet the demands of miniaturization and integration in modern electronic packaging, developing materials with low coefficient of thermal expansion (CTE) is essential to reduce thermal stress and enhance device reliability. In this study, the dense negative thermal expansion ceramic ScF3 was prepared with a CTE of -8.86 × 10-6/℃. The ScF3 ceramic was cold sintered at 150 ℃, exhibiting a low permittivity of 5.3 and a high quality factor (Q×f) of 14,700 GHz. By incorporating ScF3 to the hexagonal boron nitride (BN) ceramic, the CTE of ScF3-BN composite ceramic was adjusted to 3.36 × 10-6/℃, establishing compatibility with silicon-based chips. And finite element simulations verified that ScF3-BN composite significantly reduces thermal stress compared to Li2MoO4 or Al2O3 ceramics. Furthermore, this work demonstrates the potential of cold-sintered ScF3 to regulate thermal expansion in packaging substrates, paving the way for improved performance in next-generation electronic devices.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |