Submicron channel MOSFET´s logic under punchthrough

The characteristics of n-channel MOSFETs that make use of the punchthrough current are considered in this paper. The current conduction mechanisms of the short channel MOSFET under the bias condition of punchthrough have been studied through the use of two-dimensional computer simulation. Experimental devices with channel lengths as short as 0.5 μm were fabricated on a lightly doped substrate. Current-voltage curves of these devices showed pentode-like characteristics for smaller drain biases and triode-like characteristics for larger drain biases. A switching delay as small as 75 ps was obtained for a 13-stage ring oscillator composed of the submicron channel devices.