Semiconductors Sit for Their Portraits
November 1962 Radio-Electronics

November 1962 Radio-Electronics [Table of Contents] Wax nostalgic about and learn from the history of early electronics. See articles from Radio-Electronics, published 1930-1988. All copyrights hereby acknowledged.

This could be one of those quizzes where common items are shown close-up so they do not look familiar, and the reader's job is to figure out what he's seeing. The montage of micrographs of antimony, cadmium sulfide, germanium etched in argon, and germanium etched in hydrogen, appeared in a 1962 issue of Radio-Electronics magazine. All are elements / compounds currently (at the time and now) being researched and used in semiconductors. Knowledge of semiconductor physics has multiplied exponentially in the succeeding six decades (hard to believe that much time has passed). The Massachusetts Institute of Technology's (MIT) Lincoln Laboratory did the work shown here.

Semiconductors Sit for Their Portraits

These are microphotographs of semiconductor surfaces. Made in M.I.T.'s Lincoln Laboratory by Harry H. Ehlers of the Electronics Materials Group, they are as useful to metallurgists and solid state physicists as they are attractive. Magnification of 200 times or more makes it possible to study many important phenomena in electronic materials, including the presence and orientation of grain, identification of lattice defects, noting the presence of precipitates, and others.

The photo to the top left is of a film of antimony 1,500 Angstroms thick.

At top right is on etched cadmium sulfide surface; at bottom left, a germanium surface etched in argon at high temperatures, and at bottom right a germanium surface etched in hydrogen.