Shape of the response curve in SEU testing

An algorithm for predicting the shape of the curve describing the rise in SEU cross section with the LET of the incident particle from charge-collection measurements at a single LET, is described. Two tests of the algorithm are given, one on a bipolar SRAM and the other on a CMOS SRAM. Experimental data agrees with the algorithm for both cases. This agreement suggest that the slow rise in the SEU cross section with the LET of the incident particle is due to fluctuations in the charge collected with particles incident at the same LET.