Title :
Charge loss after 60Co irradiation of flash arrays
Author :
Cellere, G. ; Paccagnella, A. ; Lora, S. ; Pozza, A. ; Tao, G. ; Scarpa, A.
Author_Institution :
Dept. of Inf. Eng., Padova Univ., Italy
Abstract :
Flash memories are the most important among modern nonvolatile memory technologies. We are showing new results on the threshold voltage shifts in Flash memory arrays after 60Co irradiation. A (relatively) high total dose, exceeding 100 krad (SiO2), is needed to induce errors in the array, but threshold voltage shifts are all but negligible even at lower doses. These shifts can be accurately described by using a model which considers the charges generated by irradiation in all the oxides surrounding the floating gate. We are also showing that cycling (endurance) and total ionizing dose effects mutually add.
Keywords :
cobalt; dosimetry; flash memories; radiation effects; random-access storage; silicon compounds; 60Co irradiation; SiO2; charge loss; flash memory arrays; floating gate; high total dose; nonvolatile memory technologies; semiconductor devices radiation effects; threshold voltage shifts; total ionizing dose effects; Charge carrier processes; Circuits; Flash memory; Nonvolatile memory; Radiation effects; Radiative recombination; Semiconductor devices; Space technology; Spontaneous emission; Threshold voltage; Flash memories; radiation effects; semiconductor devices radiation effects; total ionizing dose;
Journal_Title :
Nuclear Science, IEEE Transactions on
DOI :
10.1109/TNS.2004.835056
