FLUOROCARBON POLYMER DEPOSITED BY INDUCTIVELY-COUPLED PLASMA OXIDE ETCHING

Polymer layers deposited by inductively couple plasma (ICP) oxide etch ing have been studied. A 180 nm thick polymer layer was deposited at t he bottom of 0.4 mu m contact holes during ICP etching with C3F8/Ar. T he deposited layer was a carbon-rich fluorocarbon polymer as indicated by electron spectroscopy for chemical analyses. The etching rate of t his layer in an ICP oxygen ashing process was very low, showing its st ability. When the carbon-rich polymer was formed at the Ti/Si interfac e, the silicidation reaction did not occur uniformly at high temperatu res. Since effective contact area became very narrow in this titanium silicide ohmic contact, high contact resistance was obtained.