底部引线式塑料封装可靠性的最终解决方案  

An Ultimate Solution to the Reliability of BLP Package

作　　者：杨建生[1] 

机构地区：[1]天水华天科技股份有限公司,甘肃天水741000

出　　处：《电子工业专用设备》2016年第2期14-22,共9页Equipment for Electronic Products Manufacturing

摘　　要：选择铜合金引线框架，来增强底部引线式塑料（BLP）封装的板上可靠性。由于其与降低封装可靠性的氧气有高度密切关系。采用铜合金引线框架，需要封装可靠性的验证过程。实施一系列测试．目的是选择最佳的铜材料，找到粘附指标参数。试验结果表明铜合金引线框架和芯片塑封材料（EMC）之间的粘附强度．受到合金成分、氧化层厚度和氧化铜／氧化亚铜率的影响。其中．粘附指标参数证明为氧化铜／氧化亚铜率。当粘附指标参数下降到0．2～0．3时，得到最高的粘附强度。而不管合金成分和氧化物厚度。从粘附试验结果看出，采用铬．锆铜合金作为54管脚PLP封装的引线框架。完成包括表面贴装能力、机械坚固性和焊点可靠性的封装可靠性和板上可靠性试验．以便与有铬一锆铜合金和42合金引线框架的54管脚BLP封装进行比较。Copper lead frame was chosen as an on-board reliability enhancement for the BLP （bottom leaded plastic） package. Adopting copper lead frame needed the verification process for the package reliability because of its high affinity with oxygen that degrades package reliability.A series of tests were performed to select best copper material and to find out the adhesion index parameter. The experimental results showed that the adhesion strength between copper lead frame and EMC （epoxy molding compound） was affected by alloy composition, oxide layer thickness, and cupric/cuprous oxide ratio. Among them, the adhesion index parameter proved to be the cupric/cuprous oxide ratio. When it falls between 0.2＇0.3, the highest adhesion strength was obtained regardless of alloy composition and oxide thickness. From the adhesion test results, the Cr-Zr copper alloy was employed as the lead frame for the 54-pin BLP package.The package reliability and on-board reliability tests including surface mountability, mechanical robustness, and solder joint reliability were done to compare the 54-pin BLP package, with Cr-Zr copper alloy and alloy 42 lead frame.

关 键 词：粘附指标参数 粘附强度 BLP封装 铜合金引线框架 焊点可靠性 

分 类 号：TN405.96[电子电信—微电子学与固体电子学]