Experimental study of back gate bias effect and short channel effect in ultra-thin buried oxide tri-gate nanowire MOSFETs

•Relation between γ and SS in thin BOX tri-gate nanowire MOSFET was studied.•Lg scaling increased both SS and γ.•Reduction of W decreased both γ and SS resulting in trade-off relation.•Reduction of H is effective to achieve large γ and small SS. We studied the relation between body effect factor and subthreshold slope in ultra-thin buried oxide tri-gate nanowire MOSFETs with various gate lengths, nanowire widths, and nanowire heights. As gate length decreases, body effect factor increases due to the enhancement and suppression of the short channel effect with positive and negative back gate bias voltage, respectively. The reduction of nanowire width leads to the decrease in both body effect factor and subthreshold slope resulting in trade-off relation, whereas better subthreshold slope and larger body effect factor were achieved by thinning nanowire height.