Interaction of nuclear environment with MNOS memory device

This paper reports on the results of an investigation of the interaction of a nuclear environment with a metal-gate, silicon nitride, silicon dioxide, silicon-on-sapphire memory device. The test device was a 63-bit (7 words by 9 bits) three-terminal device. The tests were as follows: (1) transient photocurrent, (2) transient annealing, (3) total dose, (4) survivability, and (5) neutron tests. Facilities at AFCRL were used in the first four tests and at the Aberdeen Pulse Reactor for the last test. Samples were irradiated under power. Both interrogated and passive words containing “1” and “0” states were investigated. Transient photocurrent and annealing data were obtained with the Linac operating in the electron mode. Electron energy was 10 MeV and pulse widths of 20 nanoseconds and 4. 5 microseconds were used. Total dose data was obtained with a cobalt-60 source as well as the reactor. A Flash X-ray generator operating in the electron mode (20-nanosecond pulse) was used to determine survivability rates.