Yingqi Ma

SEE characteristics of small feature size devices by using laser backside testing

This paper presents single event upset (SEU) and single event latch-up (SEL) characteristics of small feature size devices by laser backside testing method, which is dedicated to dealing with the increasing metal layers on the front side of integrated circuits. The influence of test data pattern on SEU threshold and cross-section is investigated. The supply current state of micro latch-up for deep sub-micron SRAM is described. The laser energy thresholds were correlated to heavy ion thresholds LET to determine an empirical relationship between laser energy threshold and heavy ion LET. This empirical relationship was used to estimate the equivalent laser LETs for devices fabricated in small feature sizes. Moreover, the SEU of a Power PC CPU fabricated with 90 nm SOI CMOS process has been tested, which indicates that the laser backside method could be used to evaluate SOI small feature size devices.

Comparison of single-event upset generated by heavy ion and pulsed laser

Single-event upset (SEU) is investigated using heavy ion and pulsed laser. The measured SEU cross sections of D and DICE flip-flops are compared. Measurement results indicate pulsed laser is capable of inducing similar SEU to those induced by heavy ion. 3D-TCAD simulation is performed to investigate the factors to impact pulsed laser induced SEU. Simulation results show that the beam spot size significantly impacts SEU cross sections in both low and high laser energy while the variation of the equivalent LET only impacts SEU cross sections in the low laser energy.