3-D modelling of IC interconnect using OpenAccess and Art of Illusion

Abstract

In search of higher speed and integration, the integrated circuit (IC) technology is scaling down. The total on-chip interconnect length is increasing exponentially. In fact, interconnect takes up the most part of the total chip area. The parasitics associated with these interconnect have significant impact on the circuit performance. Some of the effects of parasitics include cross talk, voltage drop and high current density. These issues can result in cross-talk induced functional failure and failures due to IR drop and electro-migration. This has resulted in interconnect- driven design trend in state-of-the-art integrated circuits. Reliability analysis, that includes simulating the effects of parasitics for voltage drop, current density, has become one of the most important steps in the VLSI design flow. Most of the CAD/EDA tools available, map these analysis results two dimensionally. Al- though this helps the designer, providing a three dimensional view of these results is highly desirable when dealing with complex circuits.

In pursuit of visualizing reliability analysis results three dimensionally, as a first step, this work presents a tool that can visualize IC interconnect three di- mensionally. Throughout the course of this research open source tools were used to achieve the objective. In this work the circuit layout is stored as an OpenAc- cess database. A C++ program reads the design information using OpenAccess API and converts it to the .OBJ file format. Art of Illusion, an open source 3D modeling and rendering tool, reads this .OBJ file and models the IC interconnect three-dimensionally. In addition, Eclipse, an open source java IDE is used as a development platform. The tool presented has the capability to zoom in, zoom out and pan in real time.