Methods of fabricating integrated circuits including metal silicide contacts extending between a gate electrode and a source/drain region

Abstract

The presence and absence of sidewall spacers are used to provide discontinuous and continuous contacts respectively, between a gate electrode and a source/drain region. In particular, first and second spaced apart gate electrodes are formed on an integrated circuit substrate. A source/drain region is formed in the integrated circuit substrate therebetween. The first electrode includes a first sidewall spacer on a first sidewall thereof facing the second gate electrode. The second gate electrode is free of (i.e. does not include) a sidewall spacer on a second sidewall thereof facing the first electrode. A metal silicide layer is formed on the first gate electrode, on the second gate electrode and extending from the second gate electrode onto the second sidewall and onto the source/drain region. The first sidewall spacer is free of the metal silicide layer thereon. The metal suicide layer is preferably formed by forming a metal layer on the first gate electrode, on the first sidewall spacer, on the source/drain region, on the second sidewall and on the second gate electrode. The metal layer is reacted with the first gate electrode, the source/drain region, the second sidewall and the second gate layer, to thereby form the metal silicide layer on the first gate electrode, on the second gate electrode and extending from the second gate electrode onto the second sidewall and onto the source/drain region. The metal layer is then removed from the first sidewall spacer.