Time-domain charge pumping on silicon-on-insulator MOS devices

Abstract

Time-domain charge pumping, which monitors transient currents during the charge pumping process, was applied to silicon-on-insulator (SOI) MOS gated p–i–n diodes. We found that the transient electron current is strongly dependent on the polarity of the back (substrate) gate. Specifically, when the back gate is positively biased, the current peak caused by the electron trap to the interface defects was found to disappear (or significantly weaken), which was attributed to the charging effects of the trapped electrons. The present results reveal the importance of the formation of the back channel and provide important information for further detailed analysis of the charge pumping process in SOI MOS devices.

Direct observation of electron capture and emission processes by the time domain charge pumping measurement of MoS2 FET

“…9 Since the electron capture and emission processes are confirmed in the transient current response, the interface quality should be evaluated quantitatively. In the case of conventional CP, 11,12,16 Nit is estimated, which is the interface trap density averaged through the "whole" energy gap. In case of MoS2 FET, however, the recombination current during a gate voltage pulse between the conduction and valence bands cannot be obtained because there is no electrical connection to the valence band.…”

“…It should be noted that the observation of the current peak in Si is possible only after the interface states are intentionally formed by electrical stress. 15,16 Therefore, the present stage of the high-k/MoS2 interface quality is worse than that for Si. The proper time condition with relatively high S/N is tr = tw = tf = 100 s.…”

“…Recently, CP has been examined with respect to time domain measurement, where the transient currents are monitored directly during a single VG pulse with ramping and falling times of ~10 s using a fast acquisition system. [14][15][16] The main outcome is the detection of the clear difference in the capture and emission process of electrons to the interface states. In addition to the transient current response for gate capacitance, the current peak is observed during electron capture, while the broad tail is detected during electron emission.…”