Thin-film circuit technology part III — Active thin-film devices

The insulated-gate thin-film transistor is the active device under the most intensive investigation today. Solutions to its problems should simplify the future development of other types of active thin-film devices The first article in this series¹ discussed thin-film circuits and the considerable success that has been achieved in the fabrication of inactive circuit elements by evaporative techniques. However, the thin-film technology will not be complete until active devices can be made compatibly with the inactive ones. At present the active elements — usually transistors — are soldered on the circuit boards. The usefulness of evaporated circuitry would be immeasurably increased if the active devices themselves were also evaporated.