학술논문

NCTUcell: A DDA- and Delay-Aware Cell Library Generator for FinFET Structure With Implicitly Adjustable Grid Map
Document Type
Periodical
Source
IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems IEEE Trans. Comput.-Aided Des. Integr. Circuits Syst. Computer-Aided Design of Integrated Circuits and Systems, IEEE Transactions on. 41(12):5568-5581 Dec, 2022
Subject
Components, Circuits, Devices and Systems
Computing and Processing
Routing
Transistors
Wires
FinFETs
Cell synthesis
coupling capacitance
drain-to-drain abutment (DDA)
routing
Language
ISSN
0278-0070
1937-4151
Abstract
For the 7-nm technology node, cell placement with a drain-to-drain abutment (DDA) requires additional filler cells, increasing the placement area. This is the first work to fully automatically synthesize a DDA-aware cell library with the optimized number of drains on cell boundary based on ASAP 7-nm PDK. We propose a DDA-aware dynamic programming-based transistor placement. Previous works ignore the use of the M0 layer in cell routing. We first propose an ILP-based M0 routing planning. With M0 routing, the congestion of M1 routing can be reduced and the pin accessibility (PA) can be improved due to the diminished use of M2 routing. We also present a quadratic-programming based-coupling-capacitance-aware initial routing to optimize cell delay, cell area, and M2 usage. To improve the routing resource utilization, we propose an implicitly adjustable grid map, making the maze routing able to explore more routing solutions. The experimental results show that block placement using the DDA-aware cell library requires fewer filler cells than that using the traditional cell library by 25.1%, which achieves a block area reduction rate of 0.97%.