Threshold Voltage -1 Consider an NMOS:as the gate voltage is increased,the surface under the gate is depleted.If the gate voltage increases more, free electrons appear under the gate and a conductive channel is formed. 40.1V 40.1V +0.1V n p-substrate p-substrate Negative lons b +0.1V +0.1V p-substrate p-substrate Electrons c (a)An NMOS driven by a gate voltage,(b)formation of depletion region,(c)onset of inversion, and(d)channel formation As mentioned before,in NMOS devices charge carriers in the channel under the gate are electrons. 2西72020/3/7 8 SM 17 EECE 488 ± Set 1: Introduction and Background Threshold Voltage - 1 (a) An NMOS driven by a gate voltage, (b) formation of depletion region, (c) onset of inversion, and (d) channel formation ‡ Consider an NMOS: as the gate voltage is increased, the surface under the gate is depleted. If the gate voltage increases more, free electrons appear under the gate and a conductive channel is formed. ‡ As mentioned before, in NMOS devices charge carriers in the channel under the gate are electrons