Introducing Expert
ULSI Layout Processor for PC-based Platforms

Expert is a state-of-the art hierarchical full-custom ULSI layout editor including advanced design functions. Running on PCs under Windows NT or Windows 95, it easily handles multimillion object ULSI designs. Expert includes special navigation and inspection tools useful for designers of physical layout of integrated circuits. It is also recommended to all those who are interested in exploring and reusing large hierarchical integrated circuit layout designs.

Expert provides high-speed editorial and verification functions and advanced graphical tools. It has no restrictions on layout complexity neither on the number of IC components or on the type of geometrical limitations set for specific layouts. A proprietary high speed data base allows efficient processing of ULSI designs of any size, density, complexity of hierarchy, or number of cells. The dimensions of processed layouts are limited only by the amount of available disk space.

The chip navigation tool "Chip Rover" presents the layout hierarchy in the form of level-by-level expanded hierarchy tree of instances/ cells. It gives easy-to-use ways for exploring complex hierarchical VLSI designs. Chip Rover allows fast loading of a required cell instanced at any level of hierarchy, marking arbitrary instances on the background of the whole chip, and displaying selection and search results. Chip Rover is a key component of Edit-in-Place, selection operations, and Multiview Navigator functions.

Expert delivers an advanced environment and set of features to support hierarchical design and editing of VLSI layout. These functions are provided by a number of specific Cell/Hierarchy operations. They make possible a user-defined logical subdivision of layout and full control of hierarchical structure. The key operations are recursive Edit-in-Place, hierarchical view settings, flattening and grouping into cells. Edit-in-Place gives an easy and convenient way to edit objects of a cell within the surroundings of any its instance, while the group of hierarchical view operations creates a flexible environment for the execution of basic editorial functions, which allows various levels of detail, ranging from showing the floorplan level to presenting all-level objects together with instance frames.

Expert supports polygon level entry, as well as component level layout entry. A comprehensive set of objects is available for editing complex layouts: cell instances, arrays, polygonal regions, rectangular boxes, text for labeling of cells/ primitives, multiple-style wires of any width, ellipses, and rolled regions. All-angle, 90 and 45-degree geometries, arcs and rolled drawings provide advanced editing capabilities for high-frequency and mixed-signal designs.

The editor is supplied with a highly efficient Hierarchical Locator inspecting any desired cell instance or primitive at any level of hierarchy. It serves as a convenient tool for fast browsing and editing of IC components located inside the specified area.

Expert is equipped with a flexible grid setup providing both user-definable and automatic (zoom-adjustable) grids and subgrids in several representations. There are convenient means for fast on-layout measurements: automatically graduated axes, flexible polyline rulers, distance meter and cursor locator. Layer settings, arrangement, and visibility are easily controlled from Layer bar and Layer Setup dialog.

The advanced Multiview Navigator uses Map View for controlling all opened layout windows. Multiview Navigator is supplied with convenient tools for resizing/ focusing of dependent windows. It allows users to view the layout at different resolutions and to globally monitor the corrections made in a locally viewed work area.

A key feature of Expert is the built-in verification subsystem and set of automatic operations:

  • Highly efficient and flexible Design Rule Checker.
  • Clipping Out of arbitrary layout areas with the capability of saving the obtained pieces as separate cells. This clip-out feature preserves the hierarchy of instances that lie completely in the clipped area.
  • Merge, Hollowing, Resizing and Cutting by arbitrary polylyne of layout regions.
  • Fast automatic Extraction of Nodes as sets of electrically connected primitives from several layers.
  • The Routing tool providing fast automatic construction of wires (routes) between pairs of objects or points.

Note the all mentioned operations (especially DRC) require intelligent geometry processing implemented on the based of proprietary extensions of scan-line technique, developed in SILVACO's CAD Research Center.

Figure 1. Expert's hierarchical Locator Tool.


Figure 2. Built-in DRC: Script running.


Figure 3. Clip out operation: A piece of layout is saved as new cell with hierarchy preserved whenever possible.


Figure 4. Multiview Navigator: Map view shows positions of all opened windows.