RADIATION EVALUATION OF AN ADVANCED 64MB 3.3V DRAM AND INSIGHTS INTO THE EFFECTS OF SCALING ON RADIATION HARDNESS

In this paper, total ionizing dose radiation evaluations of the Micron 64 Mb 3.3 V, fast page mode DRAM and the IBM LUNA-ES 16 Mb DRAM are p resented. The effects of scaling on total ionizing dose radiation hard ness are studied utilizing test structures and a series of 16 Mb DRAMs with different feature sizes from the same manufacturing line. Genera l agreement was found between the threshold voltage shifts of 16 Mb DR AM test structures and the threshold voltage measured on complete circ uits using retention time measurements. Retention time measurement dat a from early radiation doses are shown that allow internal failure mod es to be distinguished.