Patent ID: 6162586
Filing Date: 2000-12-19
Classification: G03F,H01L

Abstract:
A method for substantially preventing footings from forming in a chemically amplified deep ultra violet photoresist layer upon exposure and development of the layer to improve the resolution of the development of the chemically amplified deep ultra violet photoresist layer in deep ultra violet photolithography processes, comprising the operations of:forming a bottom titanium nitride layer over an oxide layer of a semiconductor substrate;forming an aluminum metallization layer over the bottom titanium nitride layer; andsubstantially preventing the formation of footings in the exposed and developed chemically amplified deep ultra violet photoresist layer by forming a top titanium nitride layer over the aluminum metallization layer and before forming the chemically amplified deep ultra violet photoresist layer over the top titanium nitride layer, the top titanium nitride layer being a dense titanium nitride film having a grain size of between about 3 nanometers and about 80 nanometers, the forming of the top titanium nitride layer including,placing the semiconductor substrate in an ionized metal plasma chamber having an RF powered coil and a titanium target;introducing an argon gas and a nitrogen gas into the ionized metal plasma chamber; andpressuring up the ionized metal plasma chamber to a pressure of between about 10 mTorr and about 50 mTorr;whereby the dense titanium nitride film substantially resists combination with components of the exposed chemically amplified deep ultra violet photoresist layer to prevent the formation of footings in the exposed and developed chemically amplified deep ultra violet photoresist layer formed over the dense titanium nitride film.