Low damage cryogenic etching of porous organosilicate low-k materials using SF6/O2/SiF4статья
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 31 декабря 2013 г.
Авторы:
Liping Zhang,
Rami Ljazouli,
Philippe Lefaucheux,
Thomas Tillocher,
Remi Dussart,
Mankelevich Yuri A.,
de Marneffe Jean-Francois,
de Gendt Stefan,
Baklanov Mikhail R.
Аннотация:Low temperature plasma etching of porous organosilicate low-k films is studied, in an ICP chamber with cryo-cooled substrate holder, using Fluorine-based plasma discharges. It is demonstrated that plasma-induced damage is significantly reduced when the base temperature is below a threshold Tc that depends on pore size of low-k materials. For T < Tc, almost no carbon depletion is observed and the k-value degradation is negligible. It is shown that protection occurs mainly through the condensation of the etch by-products and their ability to seal the open pores against radical diffusion. By addition of SiF4 and O2 into the gas discharge, plasma-induced damage is further reduced, as a result of SiOxFy deposition. Vertical trench profiles are obtained in patterned structures, using an inorganic hard mask. The damage reduction mechanism is discussed and a protection model is proposed.