3. Radiation Hardened by Design

The major work introduced in this book is to develop a megagray-radiation-tolerant ps-resolution time-to-digital converter (TDC) for a light detection and ranging (LIDAR) application. In this chapter, major radiation effects in complementary metal–oxide–semiconductor (CMOS) integrated circuits (ICs) are introduced. The total ionizing dose (TID) effects are of most concern to this work since they have the largest impact on analog performance of a system. Hierarchical radiation hardened by design (RHBD) strategies are then proposed to improve the radiation tolerance of CMOS devices from four levels: system level, circuit level, device level, and layout level. Finally, the radiation hardness assurance qualification procedure is also given, which has been followed during TID performance evaluation of the demonstrated CMOS ICs presented in this book.