Defect Tolerant Molecular Electronics:
Algorithms, Architectures, and Atoms

Philip J. Kuekes
Computer Architect
Quantum Science Research
Hewlett-Packard Laboratories


The integrated circuit, manufactured by optical lithography, has driven the computer revolution for three decades. If we are to continue to build complex systems of ever-smaller components, we must find a new technology that will allow massively parallel construction of electronic circuits at the atomic scale.

Our Science paper (James R. Heath, Philip J. Kuekes, Gregory S. Snider and R. Stanley Williams, A Defect Tolerant Computer Architecture: Opportunities for Nanotechnology, Science, v.280, 12 June 1998) presented a defect tolerant reconfigurable architecture which allows one to electrically download the designed complexity of a computer into a chemically assembled regular but imperfect nanostructure.

Our Hewlett-Packard and University of California research team is currently developing the molecular electronics building blocks and CAD algorithms for such a reconfigurable technology. We have recently demonstrated the first such building blocks (C.P. Collier, E.W. Wong, M. Belohradsky, F.M. Raymo, J.F. Stoddart, P.J. Kuekes, R.S. Williams and J.R. Heath, Electronically Configurable Molecular-Based Logic Gates, Science, v.285, 16 July 1999.) The ability of a reconfigurable architecture to create a functional system in the presence of defective components may well change the style of manufacturing in the coming century.

The industrial revolution started with inexpensive labor assembling capital intensive interchangeable precision parts. Two centuries later we may switch to supercomputer labor assembling inexpensive chemically produced imperfect parts.

Philip J. Kuekes is a member of the technical staff at Hewlett-Packard Laboratories. He got his BS in Physics from Yale University. He designed mega-op array processors in the 1970s and giga-op systolic processors in the 1980s. In 1991 he joined HP Laboratories as Project Manager for Teramac, a trillion operations per second reconfigurable computer. Teramac has been configured to perform DNA sequence matching, volume visualization, and MRI based brain artery detection at 100 times workstation performance. Teramac is the largest defect tolerant processor ever made. Three quarters of the 864 chips in Teramac have defects. His current research interests are at the intersection of massively parallel computer architectures and chemistry. As a researcher in the HP Defect Tolerant Moletronics effort, he is investigating a reconfigurable architecture that allows one to electrically download the designed complexity of a computer into a chemically assembled regular but imperfect nanostructure.