Physical limits in digital electronics

Miniaturization has steadily increased the economic usefulness of digital electronics through the past two decades. A variety of physical arguments are brought to bear on the question of how far miniaturization can be extended. The implications of the laws of quantum mechanics and thermodynamics for information storage are examined. The need for power dissipation in electrical information processing is demonstrated and the limits set on miniaturization by the problems of removing the heat thereby produced are estimated. limits with origins in properties of the materials used to make electronic devices are reviewed. The potential performance of various technologies based on nonsemiconductor phenomena is estimated and compared with the limits found for planar silicon technology. Attempts are made to guess at all of the many unknown parameters that enter into broadly applicable quantitative expressions of the properties of logic circuitry so that actual values of the limits can be estimated.