High-accuracy extraction of buried-channel m.o.s. transistor threshold voltages

A new experimental method is presented, which yields threshold voltages and their dependence on substrate bias for buried-channel, usually ion-implanted m.o.s. transistors with an accuracy typically < 10 mV. The extraction follows from two current measurements in the linear region, one as a function of gate voltage and fixed substrate bias, the other as a function of substrate bias roughly at the flat-band voltage.