Investigation of Buried-Well Potential Perturbation Effects on SEU in SOI DICE-Based Flip-Flop Under Proton Irradiation

The effects of buried-well potential perturbation under the buried-oxide (BOX) layer are studied in both a heavy-ion single event upset (SEU) test and a high-energy proton-SEU test of a silicon-on-insulator (SOI) dual interlocked storage cell (DICE)-based flip-flop. Their dependence on incident angle and back bias is discussed. We fabricated both DICE-based flip-flop and conventional flip-flop, which are designed as 80 000-stage shift-register chains. In a heavy-ion test, a considerable number of SEUs were observed at back bias exceeding 2.4 V, and a ten-times larger SEU-cross section was finally recorded at back bias of 3.0 V compared with the total active area of a DICE-based flip-flop cell. This marks the first case where DICE topology was found to be broken by buried-well potential perturbation on an SOI DICE-based flip-flop. In a proton test, one error was observed at back bias of 2.0 V. The SEU rate in the Van Allen belt at an altitude of 2300 km and an inclination of 90° was estimated as being once every 5 years.