vlsi design tools

VLSI Tool Overview

Process and Device Simulation

SUPREM a process simulation tool and PISCES a device simulation tool were developed in Professor Dutton’s TCAD group at Stanford in the 80s and have evolved into commercial products now sold by Silvaco – SSUPREM4 – and Synopsys – TSUPREM4 and MEDICI -. MINIMOS is another comprehensive device simulation tool developed in Professor Selberherr’s group in the Institute for Microelectronics at Technical University of Vienna (TUV). FLOOPS and FLOODS are also industrial strength TCAD tools from Professor Law’s group at the University of Florida. All the above programs were developed for different flavors of UNIX and the source is available for academic use from the corresponding groups at Stanford, TUV and University of Florida.

John Faricelli has compiled PISCES and MINIMOS for the Windows operating system and made them available through his website. They run from the command line (DOS environment) under Windows 2000 or XP and thus have no graphics capabilities. POSTMINI is a very nice graphics postprocessor also maintained by John that runs under many operating systems including Linux and Windows and is capable of interfacing with the output file formats from a number of CAD tools including SUPREM, PISCES, MINIMOS, SPICE e.t.c. A Windows version for SUPREM-IV (A-9130) was compiled at the University of Swansea and it is available from Professor Allen’s web site at Georgia Tech.

MICROTEC is an easy to use process/device simulator from Siborg that runs under windows.

ACES is an anisotropic etch simulator from Professor Liu’s group at the University of Illinois that is now archived here. It accepts a mask input in a variety of formats and generates a 3D etch profile. Unfortunately this program runs only under win95 or win98. The simulation algorithms are discussed in a worthwhile reading journal paper.

PROLITH is a photolithography simulator originally developed by Chris Mack and is now a commercial product available from KLA TenCor.

SimWindows is an easy to use, 1D device simulator written by David Winston at the Optoelectronics Computer Systems Center of the University of Colorado. You can download some information from here. The program is no more available on the U. Colorado site. Here is a local copy (zip).

The website has links to a number of tools and resources for atomistic level materials, process and function design.

Circuit Simulation and Models

SPICE and its various commercial incarnations has its origins in Nagel’s work in Prof. Pederson’s group at Berkeley. HSPICE from Avant! (now Synopsys) is an industrial strength version of SPICE but pricey as well. B2 Spice and TopSPICE are low cost programs from Beige Bag Software and Penzar respectively that have a nice schematic capture interface and behavioral extensions. WinSpice has a simple windows command line interface and is port of Berkeley SPICE 3f4 program by Mike Smith available from his website. If you are running Linux the article here is helpful in getting Berkeley SPICE 3f4 up and running. A windows compilation of Berkeley SPICE 3f5 that includes some of the latest MOS models from Berkeley (BSIM3v3.2.4, BSIM4.4.0, BSIMSOIv3.2 for SOI devices) and a minimalist but functional windows interface is available from the website of Prof. Vogt at the University of Duisburg. A local copy can be found here. LTSpice/SwitcherCAD III available as a free download from Linear Technology’s website is a SPICE simulator for windows that has a nice schematic capture interface, behavioral extensions and it is very fast (AGA favorite!). Finally there is a version of SPICE3f5 compiled by by Charles Williams for the Macintosh from University of Exeter (MacSpice3f5).

ICAP from Intusoft, and PSPICE from OrCAD are commercial enhanced Windows versions of SPICE. Dolphin SMASH is another industrial strength SPICE simulator with many powerful functional extensions. A limited version of the program (good for most class related work) is available free from the Dolphin website. TSPICE from Tanner uses different numerics but has compatible input format and it has its origins in the CaZM simulator from the Microelectronics Center of the University of North Carolina (MCNC).

MOS models: The more recent versions of the BSIM model including a BSIMSOI model can be obtained from Berkeley. The EKV model from EPFL is an excellent model now available in many versions of SPICE including LTSpice from Linear Technology and SMASH.

The netlists and device parameters for SPICE decks in different commercial and academic version of SPICE are slightly different. This document (long!) from Agilent lists compatibilities between SPICE , HSPICE and SPECTRE.

eCIRCUIT CENTER is a very nice web site that includes tutorials and a wealth of hands on information on circuit design and simulation with SPICE, including a brief history, and some down to earth discussion of the numerical algorithms.

Behavioral Simulation

ModelSim is an industrial strength high level VHDL/Verilog simulator from Mentor Graphics. A light version of it (ModelSim XE II) is included with Xilinx’s ISE WebPACK and a free license can be obtained from Xilinx.

Dolphin SMASH: Multi-domain simulator, a version of SPICE with support for VHDL, VHDL-AMS and other simulation extensions – free download with limited abilities-. HAMSTER site: VHDL-AMS simulation environment -free download-. The Hamburg site for VHDL provides a wealth of information on high level behavioral modeling and synthesis tools. Here is another comprehensive site for analog and mixed signal extensions to VHDL (VHDL-AMS).

Behavioral Synthesis

FPGA vendors such as Xilinx and Altera have their own tools for synthesis from VHDL. For ASIC design, Synopsys and LeonardoSpectrum from Mentor Graphics can be used with the Tanner libraries to synthesize custom layout from VHDL.

Mathematical Modeling

MATLAB scientific and technical computing. Download Kermit Signon’s Matlab primer (somewhat dated by still useful) here. There is a student version of Matlab at a very reasonable price! It includes a handful of toolboxes and I encourage you to buy it for personal use. For what you get it is a pretty good deal! For other tutorial introduction to MATLAB and “how to” follow the links from this UMCP site. The industry standard tool for finite element analysis is ANSYS. FEMLAB from COMSOL is another finite element analysis and multiphysics simulation tool that is easy to learn. FEMLAB used to require MATLAB for the numerics but version 3.x comes with its own solver.