Optimization of Deep Trench Isolation on 0.18μm SOI BCD Technology for Automotive Application

Deep trench isolation (DTI) is widely used in high voltage BCD technologies in SOI due to its great area shrinkage and excellent isolation capability. X-FAB has utilized the benefits of DTI which enables broad portfolio of highly modular high voltage solution in XT018 [1] [2] and XT011 technology node for automotive applications. The DTI is used for device termination and isolation between adjacent device in circuit to prevent parasitic channel formation, which shown in Fig. 1. As the DTI process integration is rather complex and challenging, the process needs to be well-optimized and robust enough to achieve sustainable manufacturability. This work describes the improvement of defectivity, electrical, yield, as well as reliability performance realized by DTI process optimization.