 A design-for-manufacturing standard-cell library solution specifically targeted at improving yield has been created by Prolific Inc., Circuit Semantics Inc. and Legend Design Technology Inc. As designs move to ever-finer process geometries below 130 nanometers, several physical effects have a negative impact on yield and reliability. To deal with those effects, said the companies, engineers will have to apply design-for-manufacturing (DFM) techniques. The companies assert that the logical place to start is with standard-cell libraries. Standard cells are critical in achieving a manufacturable design, blending logic design information (netlists) with design trade-offs of performance, power, area and yield (cell architecture) and manufacturing process requirements (design rules). Moreover, standard cells are used repeatedly throughout a design. Those factors make them the logical focus of a move toward manufacturability, said the companies. But applying DFM techniques like guardbanding without guidance can often increase the overall chip area. To deal with that problem, Prolific has developed new DFM standard-cell libraries. Prolific claims that 70 to 80 percent of DFM practices can be implemented without an area penalty. And it is within those parameters that Prolific has built the new DFM library solution. Manufacturing enhanced
Prolific says its silicon intellectual property (IP) addresses more than 20 manufacturing-enhancement practices. These include decreasing the likelihood of contact and via failures by increasing contact/via metal overlap; using wider and longer metal end-of-line extensions; and using redundant vias and contacts. The number of critical features can be reduced by limiting poly and diffusion routing, using straight transistors, minimizing the number of vertices and avoiding forbidden pitches, the company said. Optical proximity correction and other resolution enhancement technologies (RETs) are also critical aspects of improving manufacturability, said Prolific. Integrating RET-friendly design styles will not only reduce RET layout-processing complexity and mask-making cycle time and cost, it will also ensure best silicon performance. DFM RET recommendations include using rectangular line ends, forbidding circular or oval shapes, and avoiding short-cropped corners, small zigzags and jogs, and certain pitches. The Prolific DFM silicon IP is integrated with the company's ProGenesis layout generation tool, the DynaCell characterization tool from Circuit Semantics and the MSIM circuit simulator from Legend Design Technology. The combination, said the companies, allows users to home in on creating DFM-savvy designs that don't suffer area penalties. Pricing for the Prolific DFM IP starts at $25,000 for 100 cells. The IP is pre-optimized for 130-nm and 90-nm process technologies, customer design requirements (performance, power, area) and yield. Michael Santarini is senior editor covering electronic design automation for EE Times. | 
