Properties of posttreated low kappa flowfill (TM) films and their stability after etch, resist and polymer strip processes

The as-deposited Flowfill (TM) layer requires an anneal to remove moisture from the film. Alternative ways of annealing Flowfill (TM) films have been investigated. An R.F. plasma anneal was evaluated with respect to basic fil m properties. The composition was measured by FTIR spectroscopy, Rutherford backscattering and electron recoil detection analysis. The film stability with regard to etch, resist strip and wet via strip processes was tested by measuring the refractive index, FTIR spectra and kappa values. Temperature stability was tested up to 750 degreesC using temperature desorpton spectr oscopy. The film was found to be very stable up to 500 degreesC and resista nt to typical post dielectric process sequences. The wet etch rate of the p lasma treated low kappa films was also tested and found to be lower than th at of thermal silicon dioxide. (C) 2001 Elsevier Science B.V. All rights re served.