DESIGN CONCEPT FOR RADIATION HARDENING OF LOW-POWER AND LOW-VOLTAGE DYNAMIC MEMORIES

A radiation hard low power, low voltage dynamic memory is obtained by the use of a dummy cell concept. Compared to conventional dummy cell c oncepts, this concept applies a fully sized dummy cell. By optimizing the dummy cell precharge voltage for 5 V and 3 V operation and the tim ing of the dummy word-line, the overall soft error rate (SER) of the c hip is improved by 2 orders of magnitude. An additional improvement of 1 order of magnitude is possible for 3 V operation by adjusting subst rate bias and cell plate voltage, The results are verified by an accel erated SER measurement with a radium 226 source and an additional fiel d soft error study.