N and P-channel groove-gate MOSFETs based on a self-aligned CMOS process have been fabricated and characterized. For the devices with channel length of 140nm, the measured drain induced barrier lowering (DIBL) was 66mV/V for n-MOSFETs and 82mV/V for p-MOSFETs. The substrate current of a groove-gate n-MOSFET was 150 times less than that of a conventional planar n-MOSFET, These results demonstrate that groove-gate MOSFETs have excellent capabilities in suppressing short-channel effects. It is worth emphasizing that our groove-gate MOSFET devices are fabricated by using a simple process flow, with the potential of fabricating devices in the sub-100nm range.
We investigate the negative bias temperature instability (NBTI) of 90nm pMOSFETs under various temperatures and stress gate voltages (Vg). We also study models of the time (t) ,temperature (T) ,and stress Vg dependence of 90nm pMOSFETs NBTI degradation. The time model and temperature model are similar to previ- ous studies, with small difference in the key coefficients. A power-law model is found to hold for Vg, which is different from the conventional exponential Vg model. The new model is more predictive than the exponential model when taking lower stress Vg into account.