| 摘要: |
| LGA器件具备组装密度高、电子产品体积小、可靠性高等特点，但底部焊端与壳体底面焊盘在同一水平面，在生产过程中偶发焊接后器件底部存在锡珠缺陷。锡珠在表面组装生产中是一种典型缺陷，轻则影响板级产品外观，存在质量隐患、导致电路功能异常，重则造成器件或印制板报废。通过对生产过程中会产生锡珠因素的钢网厚度、钢网开口方式、贴片压力、回流焊接温度进行优化，从而解决锡珠问题，提高LGA器件焊接合格率，减少芯片报废率，提高产品质量。 |
| 关键词: LGA器件；锡珠；网板 |
| 基金项目: |
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| LGA Device Tin Bead Cause and Control Method |
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Fu Zeyang Zhang Qi Yang Xiaojian Zhou Zhening
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Beijing Computer Technology and Application Research Institute , Beijing 100854
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| Abstract: |
| LGA devices have the characteristics of high assembly density, small size of electronic products and high reliability, but the bottom welding end and the bottom surface of the shell are in the same horizontal plane, and there are tin bead defects at the bottom of the device after welding in the production process. Tin bead is a typical defect in surface assembly production, which can affect the appearance of board level products, lead to abnormal circuit function, and cause devices or printed boards to be scrapped. Through the optimization of steel mesh thickness, steel mesh opening mode, patch pressure and reflow welding temperature, which will produce tin bead factors in the production process, the tin bead problem can be solved, the welding qualification rate of LGA devices can be improved, the chip scrap rate can be reduced and the product quality can be improved. |
| Key words: LGA device；tin bead；mesh plate |
