Method of parameter creation

Patent metadata

Field	Value
Publication number	US-10409938-B2
Application number	US-201715623549-A
Country	US
Kind code	B2
Filing date	Jun 15, 2017
Priority date	Jun 15, 2017
Publication date	Sep 10, 2019
Grant date	Sep 10, 2019

Abstract

According to one embodiment, a method, computer system, and computer program product for creating a plurality of process parameters in a circuit design is provided. The present embodiment of the invention may include receiving one parasitic extraction per layer of a circuit is used to obtain a resistance base factor and a capacitance base factor. The embodiment may further include performing Monte Carlo simulations to determine distributions of capacitance and resistance for each metal layer of the circuit, and creating scalars that scale each of the resistance base factor and the capacitance base factor to a minimum and maximum process limit. Additionally, the embodiment may include defining at least one delay corner using the created scalars, and receiving the results of one or more timing analyses performed using the resistance base factor and the capacitance base factor, and the defined delay corner to determine a delay variability per layer.

First claim

What is claimed is:

1. A processor-implemented method for creating a plurality of process parameters in a circuit design, the method comprising:
performing a plurality of up-front Monte Carlo simulations to determine a plurality of distributions of capacitance and resistance for each metal layer of the circuit;
creating a plurality of scalars that scale each of a nominal resistance value and a nominal capacitance value to a minimum process limit and a maximum process limit;
defining at least two delay corners using the created plurality of scalars; and
receiving, from a timing engine, a plurality of results of one or more timing analyses performed using the nominal resistance value and the nominal capacitance value, and the defined at least two delay corners to determine a delay variability per layer.

2. A method of claim 1 , wherein the at least two delay corners are comprised of a thick corner and a thin corner.

3. A method of claim 2 , wherein the thick corner simulates the delay variability at a maximum capacitance and a minimum resistance, and wherein the thin corner simulates the delay at a minimum capacitance and a maximum resistance.

4. A method of claim 1 , wherein greater than ten thousand Monte Carlo simulations are performed.

5. A method of claim 1 , wherein the one or more timing analyses are selected from a group consisting of a multi-corner timing analysis and a static statistical timing analysis.

6. The method of claim 1 , wherein the minimum process limit for each of capacitance and resistance is set three standard deviations from each of the nominal capacitance and resistance values in a negative direction, and the maximum process limit for each of capacitance and resistance is set three standard deviations from each of the nominal capacitance and resistance values in a positive direction.

7. A method of claim 1 , wherein both the nominal capacitance value and the nominal resistance value are instead selected from a group consisting of a fast process and a slow process.

8. A computer system for creating a plurality of process parameters in a circuit design, the computer system comprising:
one or more processors, one or more computer-readable memories, one or more non-transitory computer-readable tangible storage medium, and program instructions stored on at least one of the one or more non-transitory tangible storage medium for execution by at least one of the one or more processors via at least one of the one or more memories, wherein the computer system is capable of performing a method comprising the steps of:
performing a plurality of up-front Monte Carlo simulations to determine a plurality of distributions of capacitance and resistance for each metal layer of the circuit;
creating a plurality of scalars that scale each of a nominal resistance value and a nominal capacitance value to a minimum process limit and a maximum process limit;
defining at least two delay corners using the created plurality of scalars; and
receiving, from a timing engine, a plurality of results of one or more timing analyses performed using the nominal resistance value and the nominal capacitance value, and the defined at least two delay corners to determine a delay variability per layer.

9. A computer system of claim 8 , wherein the at least two delay corners are comprised of a thick corner and a thin corner.

10. A computer system of claim 9 , wherein the thick corner simulates the delay variability at a maximum capacitance and a minimum resistance, and wherein the thin corner simulates the delay at a minimum capacitance and a maximum resistance.

11. A computer system of claim 8 , wherein greater than ten thousand Monte Carlo simulations are performed.

12. A computer system of claim 8 , wherein the one or more timing analyses are selected from a group consisting of a multi-corner timing analysis and a static statistical timing analysis.

13. The computer system of claim 8 , wherein the minimum process limit for each of capacitance and resistance is set three standard deviations from each of the nominal capacitance and resistance values in a negative direction, and the maximum process limit for each of capacitance and resistance is set three standard deviations from each of the nominal capacitance and resistance values in a positive direction.

14. A computer system of claim 8 , wherein both the nominal capacitance value and the nominal resistance value are instead selected from a group consisting of a fast process and a slow process.

15. A computer program product for creating a plurality of process parameters in a circuit design, the computer program product comprising:
one or more computer-readable non-transitory tangible storage medium and program instructions stored on at least one of the one or more non-transitory tangible storage medium, the program instructions executable by a processor, the program instructions comprising the steps of:
performing a plurality of up-front Monte Carlo simulations to determine a plurality of distributions of capacitance and resistance for each metal layer of the circuit;
creating a plurality of scalars that scale each of a nominal resistance value and a nominal capacitance value to a minimum process limit and a maximum process limit;
defining at least two delay corners using the created plurality of scalars; and
receiving, from a timing engine, a plurality of results of one or more timing analyses performed using the nominal resistance value and the nominal capacitance value, and the defined at least two delay corners to determine a delay variability per layer.

16. A computer program product of claim 15 , wherein the at least two delay corners are comprised of a thick corner and a thin corner.

17. A computer program product of claim 16 , wherein the thick corner simulates the delay variability at a maximum capacitance and a minimum resistance, and wherein the thin corner simulates the delay at a minimum capacitance and a maximum resistance.

18. A computer program product of claim 15 , wherein greater than ten thousand Monte Carlo simulations are performed.

19. A computer program product of claim 15 , wherein the one or more timing analyses are selected from a group consisting of a multi-corner timing analysis and a static statistical timing analysis.

20. The computer program product of claim 15 , wherein the minimum process limit for each of capacitance and resistance is set three standard deviations from each of the nominal capacitance and resistance values in a negative direction, and the maximum process limit for each of capacitance and resistance is set three standard deviations from each of the nominal capacitance and resistance values in a positive direction.

Assignees

• IBM

Inventors

• Foreman Eric
• Lu Ning
• Hemmett Jeffrey

Classifications

• G06F30/30 Primary

  Circuit design · CPC title

• G06F2111/08

  Probabilistic or stochastic CAD · CPC title

• G06F30/367 Primary

  Design verification, e.g. using simulation, simulation program with integrated circuit emphasis [SPICE], direct methods or relaxation methods · CPC title

• G06F17/18

  for evaluating statistical data {, e.g. average values, frequency distributions, probability functions, regression analysis (forecasting specially adapted for a specific administrative, business or logistic context G06Q10/04)} · CPC title

• G06F17/5036 Primary

  Physics · mapped topic