High Stability of Thin-Film Triodes to Nuclear-Reactor Radiation

Two thin-film triodes., fabricated by successive vacuum deposition of metal electrodes, a semiconductor, an insulator, and a gate electrode, and which exhibit good amplifying characteristics, were exposed to steady-state reactor radiation. Samples protected by a glass cover plate during irradiation survived reactor doses of 1.3 × 1016 n/cm2 (E > 0.3 Mev) and 2.4 × 1010 ergs/gm (C) without degradation. Stability in high-energy radiation environments may be attributed to polycrystallinity, conduction by majority carriers, and thinness of the thin-film devices. These results of steady-state irradiation substantiate previous indications from transient radiation tests which showed thin-film active and passive devices to be more stable than single-crystal devices by two to three orders of magnitude.