(Henry B. Linford Award for Distinguished Teaching Address) Low Temperature Plasma Etching of Copper, Silver, and Gold Films

Abstract

Copper, silver and gold films possess unique electrical and optical properties that render them suitable for various device structures as employed in integrated circuits and plasmonic devices. Traditional etching of these metal films in halogenated plasmas is difficult due to the low vapor pressure of halogenated metal species. Reasonable etch rates of Cu, Ag, and Au films are obtained with hydrogen-based plasmas. Pattern formation with hydrogen and methane plasmas yields excellent selectivity to barrier materials such as Ta and Ti and generates metal wall slopes of ~80o.

Progress and prospects in nanoscale dry processes: How can we control atomic layer reactions?

“…The introduction of a secondary H 2 plasma removed the CuCl layer. β-diketones such as 1,1,1,5,5,5-hexafluoro-2,4-pentadione, H + (hfac), [158][159][160][161] organic acids, [162][163][164][165][166] and other chemistries [167][168][169][170][171][172][173][174][175][176][177][178][179][180] have been shown to react with and remove copper oxides. However, copper oxides with different oxidation states, such as cuprous oxide Cu One approach utilizes a gas-cluster beam under acetic acid vapor to etch Pt, Ru, Ta, CoFe, and other materials.…”