CMOS process is currently the mainstream process technology for large-scale integrated circuits. The integrated circuits manufactured by this process have the advantages of low power consumption and high integration. With the continuous upgrading of semiconductor technology theories and design concepts, CMOS IC layout design is no longer a simple graphic design at the beginning, but has developed into a complex design problem that requires comprehensive consideration of various factors. Therefore, the design of layout and optimization for different problems have become more and more important. In this paper, we summarize the contents of the current mainstream CMOS layout design, common design difficulties and problems, and the optimization solutions proposed for each type of problem. The paper will first introduce the basic rules and fundamental flows of layout design, outlining their definitions and purposes. Secondly, the paper will present the optimization of the layout design taking into account different factors and problems. In particular, it focuses on the improvement schemes of the layout when facing the chip failure problems such as ESD effect and Latch-up effect.
