Analysis of angular dependence of proton-induced multiple-bit upsets in a synchronous SRAM

Angular dependence of proton-induced Multiple-Bit Upsets (MBUs) in a synchronous SRAM is reported. Experiments showed that the cross section of MBU depended on proton energy, incident direction, and physical arrangement of sensitive transistors in adjacent cells. Also analysis clarified that there was a special condition which MBU could be caused by a mechanism of Single-Event Upsets (SEUs), not by that of MBUs.