Aluminum fluoride is non volatile..would stop the etch process after a top layer is formed. aluminum chloride is volatile and the etch would continue.. Madan > Hi guys, > > why chlorine based chemistry is preferred over lets say fluorine to etch > Al in plasma etch (RIE type)? > > any help would be useful. > > thanks > > Jay Mirza > > > Madan/K.V.Madanagopal http://www.ee.cornell.edu/~madan Grad. Student, EE dept. phone:607-255-4041 (off), 266-8709 (res) 116 philips hall, Cornell Univ. fax: 607-255-8601