The effect of copper on gate oxide integrity

We have studied the effect of copper contamination after the front-end meta l-oxide-semiconductor capacitor fabrication on gate oxide integrity. The si gnificant effect of Cu contamination on the pretunneling current, in combin ation with insensitive dependence of the Fowler-Nordheim tunneling current, oxide charge density, and breakdown field on the Cu concentration, suggest s that the current leakage mechanism may be due to neutral traps generated by Cu inside oxide. In addition to pretunneling oxide leakage, a small amou nt of Cu contamination increases the interface trap density that may degrad e the device performance. (C) 2000 The Electrochemical Society. S0013-4651( 00)03-073-1. All rights reserved.