Abstract
A novel method of determining the spatial distribution of interface states of MOS transistors by charge pumping measurement has been developed. Unlike other existing methods, this method determines the absolute interface-state density profiles on the drain and source sides of transistors, extends the available scanning range, and provides self-consistent testing procedures to estimate the error induced by device simulation and testing parameters. This technique has been used to study the hot carrier degradation of submicron LDD (lightly doped drain) devices. The results indicate that the hot carrier damage occurred inside the LDD region. This damaged location can be shifted by changing the tip dose of the LDD region to improve the hot carrier performance of transistors.