PRECISE QUANTITATIVE-EVALUATION OF THE HOT-CARRIER-INDUCED DRAIN SERIES RESISTANCE DEGRADATION IN LATID-N-MOSFETS

A method is presented which allows to distinguish the drain series res istance increase from other mechanisms contributing to the drain curre nt degradation of hot-carrier stressed n-MOSFETs. Devices with differe nt channel lengths but equal damages are used. The different degradati on mechanisms are characterized quantitatively and a model for the dra in current degradation is presented. For short stress times, the drain current degradation is dominated by series resistance degradation. Fa r long stress times, however, the contribution of the mechanisms attri buted to an ''equivalent channel length increase'' prevails. (C) 1998 Elsevier Science Ltd. All rights reserved.