Temperature Dependence of Transient Electron Radiation Upset in TTL NAND Gates

The temperature dependence of transient upset caused by a 40-MeV electron flux was investigated for junction-isolated gold-doped and nongold-doped TTL NAND gate devices in the temperature range from 20 to 125°C. Data for five devices are presented. Over this temperature range, the dose rate required to upset the logical 1 and logical 0 output levels of the gate increased by a factor of between 2 and 3 for the gold-doped devices, but remained essentially constant for the nongold-doped (Schottky) devices. Schottky-clamped devices are not gold-doped, and the gold-doped devices did not employ Schottky clamps. A correlation was observed between the temperature dependence of the upset dose rate and the collector-substrate depletion width as determined from capacitance measurements for both device types. It is proposed that nearly all of the upset photocurrent for gold-doped devices is generated in the collector-substrate depletion region and that variations in the depletion width with temperature cause the observed results.