Scaling effect and circuit type dependence of neutron induced single event transient

Neutron induced single event transient (SET) has been measured on NAND and inverter (INV) chain with changing fan-out, drive strength, size of drain diffusion area, temperature and VDD on 40nm and 90nm bulk CMOS technology. As the pulse width distribution varies with the length of SET target chain as well, it is important to use the chain length similar with the actual logic circuits. Using tens of stages of target chain, pulses wider than 150ps have been rarely observed. The results of the measurement show that the SER of SET changes depending on the cell type and fan-out. SER of SET in combinational logic circuits decreases by half from 90nm to 40nm for the same gate count and the same clock frequency.