【摘要】 COB(ChiponBoard)是微电子和MEMS中常用的封装工艺之一,但该封装结构中由于多层异质材料耦合引入的热失配将对器件的性能和可靠性产生重要影响.建立了适于求解结构表面热变形分布的理论模型,利用数字散斑相关方法对COB封装在热载荷下的表面热变形分布进行实验测量,并比较了不同封装配置对结构热变形的影响.利用实验结果和有限元模拟验证了理论模型,并讨论了该模型在封装-器件协同设计中的指导意义.更多还原

【Abstract】 As a packaging technique, COB(Chip on Board) structure is usually used in IC and MEMS. However, the thermomechanical coupling effect because of CTE mismatch of different materials in COB will greatly affect the reliability and performance of the devices.A theoretical model for thermal deformation distribution of the chip surface in COB packaging structure is proposed. And a novel optical measurement approach named digital speckle correlation method (DSCM) was applied to study the actual deformations in COB structure under certain temperature excursions. The test data are compared with the calculated out-plane displacements of both the theoretical model and FEM simulations. And we also compared the effect of substrate type. The theoretical model was verified by the result of FEM simulations and experimental testing. And the value of the model to the package-device co-design is also discussed.更多还原