Dependence of Switching Probability on Operation Conditions in GexSe1–x Ovonic Threshold Switching Selectors

Ovonic threshold switching (OTS) selector is a promising candidate to suppress the sneak current paths in resistive switching random access memory (RRAM) arrays. Variations in the threshold voltage (
${V} _{\text {th}}$
), and the hold voltage (
${V} _{\text {hd}}$
) have been reported, but a quantitative analysis of the switching probability dependence on the OTS operation conditions is still missing. A novel characterization method is developed in this letter, and the time-to-switch- ON/OFF (
$\text{t}_{ \mathrm{\scriptscriptstyle ON}}/\text{t}_{ \mathrm{\scriptscriptstyle OFF}}$
) at a constant
${V} _{\text {OTS}}$
is found following the Weibull distribution, based on which the dependence of switching probability on pulse bias and time can be extracted and extrapolated, and the switching probability can be ensured with appropriately chosen operation conditions. The difference between square and triangle switching pulses is also explained. This provides a practical guidance for predicting the switching probability under different operation conditions and for designing reliable one-selector-one-RRAM (1S1R) arrays.