Microbeam analysis of MOS circuits

Irradiation of MOS SRAMs by energetic heavy ions results in pulses on the power lines of the device. Pulse-height analysis shows a series of peaks when the irradiation consists of identical particles incident in the same direction. Analysis through a microbeam shows that the pulses are generated by traversals of the p-n junctions making up the transistors of the device. Junctions in the memory array were found to dominate the spectrum from a CMOS device while those of the support circuitry dominate the spectrum from a DRAM.<
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