An integrated circuit design tool for modeling resistance of an interconnect specifies a structure of the interconnect in a data structure in memory in or accessible by the computer system using 3D coordinate system. For each of a plurality of volume elements in the specified structure, the tool specifies a location and one of first and second materials of the interconnect having specified resistivities, and for each volume element generates a model resistivity for the volume element as a function of resistivity of volume elements within a neighborhood of the volume element and a specified transition region length λ.

Nano-wire resistance model

A computer-implemented method and a computing system for designing an integrated circuit are provided. The computer-implemented method of designing an integrated circuit includes receiving layout data for the integrated circuit and a technology file that includes corners of a parasitic component of each of a plurality of layers included in the integrated circuit, generating parasitic component data by performing a parasitic component extraction operation on corners of a parasitic component of a layer in a timing arc on a net of the integrated circuit, the parasitic component data including delay variation data of the timing arc, and generating timing analysis data by performing a timing analysis on the integrated circuit, based on the parasitic component data.

Computer-implemented method and computing system for designing integrated circuit by considering process variations of wire

Near-threshold computing is essential for energy-efficient operation of VLSI systems, but wide performance variation and nonlinearity to process variations block the proliferation. To cope with this, in this article, we propose a holistic hardware performance monitoring methodology for accurate timing prediction in a near-threshold voltage regime. Precisely, 1) we formulate the problem of finding an efficient configuration of monitoring circuits into an instance of optimal experiment design problem and 2) propose a new timing prediction flow, consisting of statistical estimation of FEOL and BEOL process variations and a neural network-based timing inference model. For accurate control of timing margin and overcoming simulation-silicon discrepancies, 3) we introduce uncertainty learning in the prediction model construction and calibrate it through transfer learning. Furthermore, 4) we avoid time-consuming SPICE simulations in our methodology by employing efficient but accurate surrogate models. Through simulations using a 28-nm industry PDK and DK characterized at 0.6-V operation, it is shown that our methodology is highly effective, reducing the average prediction pessimism of maximum delay by 77.9% over conventional signoff results while respecting target prediction yield. Besides, for test chips fabricated using a 10-nm process, we demonstrated that our holistic approach from design to postsilicon phase in conjunction with adaptive voltage scaling reduces dynamic power consumption by 28.2%–28.8% on average, in comparison with typical supply voltage operation. 

Hardware Performance Monitoring Methodology at Near-Threshold Computing and Advanced Technology Nodes: From Design to Postsilicon

Synthesis of representative critical path circuits considering BEOL variations for deep sub-micron circuits

A computer-implemented method of extracting parasitics associated with a circuit design layout generated by modifying a previous iteration of the layout, includes, in part, identifying a first multitude of nets that have been changed in the circuit design layout relative to the previous iteration of the circuit design layout. The method further includes, in part, calculating a first multitude of parasitic capacitance values between each of the first multitude of first nets and each of a second multitude of nets disposed in proximity of the first multitude of nets. The method further includes, in part, identifying each net in the second multitude of nets as an aggressor net if a number defined by the net's associated parasitic capacitance value is higher than a threshold value. The method further includes excluding nets in the second multitude of second nets that are not identified as aggressor nets from the parasitic extraction.

Determining eco aggressor nets during incremental extraction

A method and a corresponding system for analyzing process variation and parasitic resistance-capacitance (RC) elements in an interconnect structure of an integrated circuit (IC) are provided. First descriptions of parasitic RC elements in an interconnect structure of an IC are generated. The first descriptions describe the parasitic RC elements respectively at a typical process corner and a peripheral process corner. Sensitivity values are generated at the peripheral process corner from the first descriptions. The sensitivity values respectively quantify how sensitive the parasitic RC elements are to process variation. The sensitivity values are combined into a second description of the parasitic RC elements that describes the parasitic RC elements as a function of a process variation parameter. Simulation is performed on the second description by repeatedly simulating the second description with different values for the process variation parameter.

Method for analyzing interconnect process variation

A comprehensive variation model is critical to achieve both competitive design and manufacturing yield in advanced technologies. Conventionally, as long as FEOL (front end of line) statistical model is appropriate, BEOL (back end of line) variations given by lumping multiple variation sources into few corners is enough to achieve reliable simulation results. However, as BEOL contribution is becoming more important with device scaling, simulation results with conventional corner model may not always produce optimal design margin. We thus propose a more comprehensive solution for BEOL variations characterization and modeling associated with statistical Monte Carlo simulation.

A comprehensive solution for BEOL variation characterization and modeling

A method of designing a circuit layout includes calculating a typical value representing performance characteristics for the circuit layout based on a graphic database system (GDS) file. The method further includes calculating an adjustment value based on the GDS file and at least one of a CAP corner vector or a RES corner vector, wherein the CAP corner vector is based on an eigenvector of a parasitic capacitance of the circuit layout, and the RES corner vector is based on an eigenvector of a parasitic resistance of the circuit layout. The method further includes calculating a corner value based on the typical value and the adjustment value. The method further includes modifying the GDS file if performance characteristics of the corner value fail to satisfy performance requirements of the circuit layout.

Te-Yu Liu

Papers

Method for analyzing interconnect process variation

A comprehensive solution for BEOL variation characterization and modeling

Method of designing circuit layout and system for implementing the same