关键词: 翘曲, 有限元仿真, 热-力耦合, 表面贴装技术

Abstract: To address soldering defects caused by carrier board warping during the surface mount technology process of small ceramic substrate printed circuit board assemblies (PCBAs), an integrated approach combining theoretical analysis, thermo-mechanical coupled finite element simulation, and experimental validation was employed. The evolution of the three-dimensional temperature field of the carrier board and its correlation with structural deformation were systematically investigated. Simulation results indicated that direct contact with the heating stage generated significant thermal stress due to a non-uniform thermal environment, leading to carrier warpage and a consequent reduction in component yield. To mitigate this issue by buffering the transient thermal shock, an optimized solution involving the insertion of a thermal insulation pad between the carrier and the heating stage was proposed. The results demonstrated that this solution effectively reduced the temperature gradient and temperature rise rate, achieving a warpage reduction of more than 90%. With the warpage thus controlled, the component defect rate was reduced from 6.5% to below 2.0%, resulting in a significant improvement in final component yield.

Key words: warpage, finite element simulation, thermo-mechanical coupling, surface mount technology