激光退火技术在分立器件中应用的研究

Laser Annealing Technology Application Study in Power Device

激光退火是一种激活效率高,热预算小,激活深度可控的激活工艺,对具有垂直结构的分立器件进行背面注入退火激活时,可以大大降低热预算,避免背面工艺对正面器件的影响,进一步降低超薄片在加工中因形变导致的翘曲和碎裂。本文以FS-IGBT背面注入退火为例,对激光退火工艺参数与激光退火设备硬件参数进行了研究,在传统激光退火理论模型的基础上,首次通过理论分析和实验结果验证了多光束激光退火设备的交叠时间与交叠范围、聚焦光斑尺寸、聚焦深度等重要设备参数对分立器件影响,对激光退火技术在分立器件中的应用与激光退火工艺与激光退火设备标准化及理论模型与实际相结合提供了有益参考。

Laser Annealing Technology is a doping activation solution with low thermal impact and controlled active depth.It is attractive for Power devices to avoid backside implantation activation impact to both front side device and thin wafers.In previously study some good results had been demonstrated and its theory model is discussed.In this paper,we will demonstrate a systematic study for laser annealing technology application in FS-IGBT.For the first time,some key process and tool parameters are studied beyond current classical theory model.It will be a good reference for laser annealing process/tool setup and maintenance.It also provide a new direction to improve laser annealing model accuracy by considering tool parameter impact.