Single Event Upset Vulnerability of Selected 4K and 16K CMOS Static RAM´s

Measurements of single event upset probability for several types of prototype bulk CMOS and CMOS/SOS RAM´s have been made using beams of 140 MeV krypton, 160 MeV argon and 33 MeV oxygen ions from the Lawrence Berkeley Laboratory 88-in cyclotron. Upset thresholds, determined by varying the ion species and beam-incidence angles, were used in conjunction with manufacturer-supplied information on device design parameters to estimate values of critical charge for upset. These experimental values are in reasonably good agreement with scaling predictions of Petersen et al. and Pickel. Comparison of the critical charge values deduced from experiment with predictions obtained for the 16K CMOS/SOS devices by means of SPICE and RCAP simulation codes shows discrepancies of approximately a factor of two. These discrepancies indicate the need of additional experimental and theoretical work before an adequate understanding of device response to charged particle bombardment is achieved.