表面贴装立式模块二次回流缺陷预防模型研究

Study on Defects Prventation of Vertical Surface-Mount Module during Reflow Process

立式表面贴装模块作为单板高密度布局的一种解决方案,已在业界相关产品中应用,布局在立式表面贴装模块上的表面贴装器件种类也会越来越多,这些表面贴装器件二次回流时是否会由于重力等作用产生缺陷,在业界尚未发现有相关研究。介绍了一个理论模型,该模型给出了立式模块上元器件在第二次回流是否掉件/偏位的关键值,采用试验设计(DOE)对立式表面贴装FR4模块上表面贴装陶瓷电容、SOT/SOP器件及MLF器件缺陷进行分析,对仿真模型验证回归,确定立式模块二次回流焊不发生掉件/偏位缺陷的质量面积比。

Vertical surface-mount module（VSM） is a high density distribution to effectively make use of the spatial occupation.More and more surface-mount devices（SMD） are involved in VSM to achieve the product function.Now there haven＇t be enough study of SMD defect caused by gravitation or other factors in reflow soldering.Introduces a theoretical model,the model gives the key value whether drop / deflection of component in VSM during the second reflow soldering.The study are concentrated on the defects prevention of ceramic capacitors,SOT/SOP components and MLF components in the vertical surfacemount FR4 module,which are in the state of reflow soldering and vertical complex stress,based on the analysis of results from DOE test.Construct the simulation model used to prevent the defects.