Influence of triple-well technology on laser fault injection and laser sensor efficiency

This study is driven by the need to understand the influence of a Deep-Nwell implant on the sensitivity of integrated circuits to laser-induced fault injections. CMOS technologies can be either dual-well or triple-well. Triple-well technology has several advantages compared to dual-well technology in terms of electrical performances. Single-event responses have been widely studied in dual-well whereas SEE (single event effects) in triple-well is not well understood. This paper presents a comparative analysis of soft error rate and countermeasures sensors with for these two techniques in 40 nm and 90 nm CMOS technology. First, laser fault injection on registers were investigated, showing that triple-well technology is more vulnerable. Similarly, we studied the efficiency of Bulk Built-In Current Sensors (BBICS) in detecting laser induced fault injection attempts for both techniques. This sensor was found less effective in triple-well. Finally, a new BBICS compliant with body-biasing adjustments is proposed in order to improve its detection efficiency.