Research And Implementation Of DMSA Physical Design In Nanometer Technology

With the development of integrated circuit technology, the tech-node rapidly stepsinto nanometer level. The chip’s function is more powerful under the nanometerprocess, but meanwhile the chip design is becoming more complicated. The variationsof Process, Voltage, Temperature (PVT) make the design take more process cornerinto consideration to guarantee the proper function of the chip. At the same time, withthe testing and function demands, chip will work more different modes. The seriousinfluence of corners in nanometer technology and the increasing function modes makethe Static Timing Analysis (STA) and timing closure a big challenge.This thesis analyzes the effect of MultiCorner-MultiMode (MCMM) in physicaldesign, studies on the influence and problems of STA and timing closure in MCMMdesign. For above issues, under the65nm process, this paper proposes the DistributedMulti_Scenario Analysis (DMSA) flow and timing closure flow based on DMSA. Onthe one hand, the tool PT (PrimeTime) process runs on the distributed computingplatform of DMSA to simultaneously analyze all the scenarios’ timing,and work outonly one report which includes all scenarios’ timing information. This method avoidsthe immense iterations of mode switching and analyzing large amounts of timingreports, thus improves working efficiency. On the other hand, the timing closure basedon DMSA takes all the scenarios into consideration concurrently and automaticallyfixes all the violated timing paths in different scenarios, which is quicker thantraditional flow. Thus further improves working efficiency. In short, the new designmethodology presented by this paper remarkably decreases the iterations in finaltiming signoff procedure and the design cycle, thus shortens the Time To Market(TTM) and enhances the product competitiveness.In the end, this paper takes the actual project, BES6507, as an example, based onSMIC65nm process, uses Synopsys physical design platform, applies DMSA designmethod to implement the chip physical design. And compares the results of traditionalmethod and DMSA method, verifies its feasibility and reliability. The final design datashows the new method shorten the timing signoff period of85.3%and the wholephysical design cycle of21.3%, efficiently solves the problems of long design cycleand design iteration in MCMM design, and proposes an efficient chip design methodin nanometer technology，which is meaningful and helpful.