An anomalous increase of threshold voltages with shortening the channel lengths for deeply boron-implanted N-channel MOSFET's

In relatively heavily and deeply boron-implanted n-channel MOSFET's, we found the anomalous phenomenon that the threshold voltage increases with decreasing channel length over a wide range of channel lengths. This is quite contrary to the well-known short-channel effect associated with the dependence of the threshold voltage on the channel length. It is difficult to explain this phenomenon directly by any simplified models that have been presented to date. In this brief, we present mainly the detailed experimental results of such an anomalous short-channel effect.