Abstract :
The meanings of the words microcircuits, molecular electronics, integrated circuits, and functional devices are examined with the conclusions that, as generally used, the only sensible definitions are as follows: a microcircuit is one in which connections are made between circuit elements on a microscopic scale. Molecular electronics, integrated circuits, and functional devices all have essentially the same meaning, which is that connections are made between circuit elements inside a single block of material without bringing leads out. The next order of miniaturization that is required for space vehicles and large-scale computers will use a microeletronic or molecular electronic technology in combination with conventional miniature techniques. The feasibility of very large components of systems being made by a molecular or microelectronic technique depends on the combination of many orders of magnitude reduction in manufacturing shrinkage combined with the design of circuits to tolerate unreliable or defective elements.