CAREER: Design Methodologies for Three-Dimensional Integrated Circuits

North Carolina State University, Raleigh NC

Investigators

Abstract

CAREER: Design Methodologies for Three-Dimensional Integrated Circuits PI: W. Rhett Davis, INST: North Carolina State University, Raleigh NC 27695-7911 Proposal no: 0643700 ABSTRACT: The semiconductor industry has succeeded in shrinking transistors on integrated circuits for more than 40 years, giving us dimensions now in the tens of nanometers and a market that expects new, faster chips every year. Although quantum-mechanical limits of shrinking have not yet been reached, the cost of manufacturing equipment is becoming prohibitively large, and industry experts are struggling to find ways to justify this cost. One promising approach is to stack chips vertically, thereby meeting the market's demands and re-using existing equipment to sell more chips. This process of stacking, often called three-dimensional integrated circuits (3D ICs), has been shown in prototype circuits to successfully increase the number of transistors on a chip, but it has not yet been shown to give significant improvements in speed. Theoretically, 3D ICs can increase the speed of circuits by a factor of two to five, depending on the application. The goal of this work is to experimentally discover and document the design techniques that will enable these speed improvements for 3D ICs in three ways: improved memory design, improved analysis of heat flow, and a search for applications that are especially well suited for 3D ICs. In addition to scientific discoveries, this project seeks to improve engineering education by developing a free design-kit for the latest integrated-circuit technology. All design-kits developed since 1998 have strict intellectual property controls, limiting educators' ability to use and expand them. This sub-project, called the FreePDK project, will build on the latest, most successful free design-kit with a thorough literature search and collaboration with industry, providing a much-needed boost to education and small businesses. Finally, an outreach partnership with a local community center and national education foundation will promote interest in low-cost electronics among disadvantaged students. A nationally distributed workshop curriculum to build crystal radios and a wirelessly-controlled robot will be developed tested each summer with forty middle-school and high-school students.