Open Competition 5 - Electronics and Photonics

Advanced Technology for Non-destructive, Localized, Dielectric Metrology of Future Generation Integrated Circuits

Sponsor: Neocera, Inc.

• Project Performance Period: 6/1/2002 - 5/31/2004
• Total project (est.): $3,378,801.00
• Requested ATP funds: $1,968,348.00

The $200 billion worldwide semiconductor industry is undergoing a transition in the design of integrated circuits. For years, tiny aluminum wires, separated by silicon dioxide, an insulating or "dielectric" material, have provided layers of connections to the tens of millions of transistors in a chip. This combination of materials is beginning to limit performance, so efforts are under way to improve the efficiency of signal processing by using copper wires (to reduce resistance) separated by materials with a lower dielectric constant (k) than silicon dioxide. These so-called low-k materials would make possible faster, higher-frequency ICs. This work is hampered by a lack of effective, non-destructive tools and methods for characterizing processed low-k materials -- either in research or during product manufacturing -- over the tiny distances found in today's dense ICs. In a two-year project, Neocera plans to develop technology for making non-destructive, quantitative measurements of dielectric constants at length scales (about 100 nanometers) and microwave frequencies (1-10 gigahertz) appropriate to ICs. The technology will be based on near-field microwave microscopy, a relatively new technique in which extremely small features can be resolved by using suitably fine probe tips. In this case, the probe will consist of a tapered microwave transmission line -- microwave fields will extend beyond the aperture of the tip over a distance determined by the aperture size (on the order of 100 nanometers), to achieve spatial resolution on the order of 300 nanometers with a measurement precision of 0.5 percent or better. This will require significant advances in near-field microwave microscopy -- existing instruments can image features in that general size range but cannot measure them with sufficient accuracy. Various approaches to probe design will be evaluated. Neocera plans to develop analytical and numerical models to optimize probe design and performance; develop distance-control mechanisms to allow the probe to be held very near (without contacting) the sample; and later commercialize the technology as three separate tools for use in research, process development, and manufacturing. The University of Maryland (College Park, Md.) will participate in the project, assisting with modeling and integration. ATP support is needed because Neocera, a small company, is unable to fully fund the work on its own, and other sources of R&D funding have turned the project down because of the high technical risks -- semiconductor manufacturers are skeptical because of past difficulties with microwave microscopy. The ATP support will accelerate the development of the technology by up to four years. If successful, the project will greatly increase productivity in the semiconductor industry and decrease time to market of future ICs. The instruments could be used to screen new low-k materials, improve equipment and processes, and provide in-line monitoring to control processes and enhance yield. The instruments also could be optimized for frequency ranges up to 100 GHz as IC processor speeds increase.

For project information:

Andrew Schwartz, (301) 210-1010
schwartz@neocera.com

ATP Project Manager

Thomas Lettieri, (301) 975-3496
thomas.lettieri@nist.gov