Improvement of Copper-Based LTCC via Protrusion

This paper describes the brief background and development of copper-based LTCC (Low Temperature Co-fired Ceramic) in China. Preliminary processing and reliability verification have been completed for YK33 copper-based LTCC material from Yunke Electronics Co. Ltd, Zhenhua Group. However, the results show that the finished product has serious via protrusion after sintering. To address this problem, this paper, on the one hand, improves the via protrusion by reducing the filling amount of via paste. On the other hand, the formulation of the via paste system is adjusted to increase the sintering compatibility between different materials. Both aspects have achieved the expected results and successfully controlled the via protrusion. The height of the improved via protrusion is within 20 um, which meets the requirements of chip micro-assembly on the LTCC substrate.