二极管激光器阵列封装工艺对smile效应影响因素分析

Relation between smile effect and packaging of laser diode arrays

Smile效应是限制二极管激光器阵列应用的一个重要因素。研究了激光器封装工艺对smile效应的影响,研究结果表明,造成smile效应的因素主要有两个:一是焊接过程中芯片的焊接压力不均匀;二是芯片与热沉的热膨胀系数不匹配。使用低膨胀系数的压条可以改善焊接过程中芯片压力的均匀性,而增大焊料凝固过程中的降温速率可以降低芯片与热沉的收缩量的差距,这两种方法都有利于改善smile效应。最后通过实验结果证明了以上方法在实际操作中是可行有效的。

Smile effect is a key problem that reduces the application of laser diode arrays. This paper presents the research on the relation between smile effect and the package technology. It is found that two main parameters affect the smile effect： the uneven pressure on laser chip in soldering and the mismatch of thermal expansion coefficient. Theoretically, the uneven of the pressure can be reduced by using low thermal expansion coefficient contact bar, and the shrinkage difference between laser diode chip and heat sink can be reduced by increasing the cooling rateof the solidification process. Both theoretical and experimental re suits show that these methods can significantly and fundamentally reduce the smile effect.