LAUSR

Present work focuses on quantitative effects of source/drain elevation height ($${\text{h}}_{\text{SD}}$$hSD) and side spacer dielectric material (Air, SiO2, Si3N4 and HfO2) on the current drive of non-abrupt ultra shallow junction (USJ) gate all around (GAA) MOSFETs. It has been observed that the desirable unanimous reverse trend (increase in $${\text{I}}_{\text{on}}$$Ion and decrease in $${\text{I}}_{\text{off}}$$Ioff with increase in source/drain elevation height ($${\text{h}}_{\text{SD}}$$hSD) and/or side spacer dielectric constant, $$\upvarepsilon_{\text{sp}}$$εsp). Utmost percentage improvement in $${\text{I}}_{\text{on}} /{\text{I}}_{\text{off}}$$Ion/Ioff ratio at $${\text{h}}_{\text{SD}} = 30.5\,{\text{nm}}$$hSD=30.5nm and $$\sigma_{\text{L}} = 7\;{\text{nm}}$$σL=7nm is found to be ~3000% for HfO2 while least as ~449% for Air with respect to their corresponding values at zero elevation. Thus, the increase in source/drain elevation with proper selection of side spacer is found to be a suitable approach. This will enhance the drivability as well as lower parasitic resistance in comparison to non elevated GAA MOSFETs at sub 20 nm technology node.