中文摘要：

引脚式LED芯片封装工艺中封装缺陷不可避免。基于p-n结的光生伏特效应和电子隧穿效应,分析了一种封装缺陷对LED支架回路光电流的影响。利用电磁感应定律对LED支架回路光电流进行非接触检测,得到LED芯片功能状态及芯片电极与引线支架间的电气连接情况,并对检测精度的影响因素进行分析。实验表明,该方法具有高检测信噪比,能够实现对封装过程LED芯片功能状态及封装缺陷的检测。计算结果与实验结果较好吻合。

英文摘要：

During the packaging process of lead frame light-emitting diode（LED）, packaging fault can not be avoided. Theoretical analysis shows that the packaging fault influences the loop photocurrent in LED lead frame,and the analysis is based on the photovoltaic effect of p-n junction and electron tunneling effect. The loop photocurrent is non-contact measured by law of electromagnetic induction,and the states of LED chip and its electric connection with the frame are detected. The influencing factors of the detection accuracy are analyzed. The experimental results show that the method has a high signal-to-noise ratio,and it can realize detecting for the states of LED chip and welding quality. The theoretical results are well consistent with the experimental results.