Impact of ultra-low voltages on single-event transients and pulse quenching

Abstract

Single-event transients (SET) and pulse quenching are analyzed at sub-Vt and super-Vt voltage levels. Two different inverter designs are simulated for their single-event response. These simulations show that SET pulse widths become longer with decreasing voltage for the inverter designed to work at sub-Vt voltage levels. Additionally, pulse quenching becomes significant between 0.5 V and 0.7 V for the standard 2-T inverter.

Experimental Investigation of the Joint Influence of Reduced Supply Voltage and Charge Sharing on Single-Event Transient Waveforms in 65-nm Triple-Well CMOS

“…4(a), the average pulse widths for each target are displayed as a function of the supply voltage for direct-hit SETs, when the active node is in the more sensitive state "1." As the supply voltage decreases, the average pulsewidth increases in both Au and Ca experiments, in agreement with results reported in [3]- [6], [11], [12], and [17]. At 1-V supply voltage, the distinction between SETs from Ca and Au experiments is clearly seen.…”

“…Our measurement setup enables us to simultaneously capture the response of multiple nodes for every ion hit, as well as to track the ion-hit location. This allows us to replicate a scenario similar to that used in previously reported 3-D simulations [7], [11], [12], [16], where both responses of a node that is hit (active node) and the subsequent node in the inverter chain (passive node) are being observed. We will refer to SETs from these nodes as "direct-hit" and "indirect" SETs, respectively.…”

“…The decrease of indirect SET cross sections is more pronounced, and especially strong at subthreshold voltages. While it has been confirmed that pulse quenching [7] occurs at higher VDD values and decreases the cross sections of indirect SETs compared to direct-hit ones [19], no significant evidence was found that pulse quenching also causes the cross section reduction at lower voltages [11], [12]. By looking at the typical quenched SETs observed during the Au experiment in Fig.…”

“…If multiple collecting nodes are made to react in the opposing manner, the individual node contributions can cancel each other out, as proposed and demonstrated in [7]- [10]. It has been shown in simulations that charge sharing can also be observed under low-voltage operation [11]. Even though struck nodes show increase in produced SET pulse widths when the supply voltage is decreased, Qin et al [12] suggest that pulse widths of propagated SETs may actually decrease, thanks to the charge sharing effect.…”

Alpha-particle and neutron-induced single-event transient measurements in subthreshold circuits

“…Previous work on a Schmitt trigger SET characterization circuit used in this work was originally described with supporting simulations [13] and with data being presented on a 65-nm version of the test structure [14]. Due to the aforementioned high noise margin present in a Schmitt trigger inverter during super-Vt operation, SETs are not able to propagate in a Schmitt trigger above a certain voltage.…”