화학공학소재연구정보센터
Journal of Vacuum Science & Technology A, Vol.16, No.3, 1577-1581, 1998
Evaluation of trifluoroacetic anhydride as an alternative plasma enhanced chemical vapor deposition chamber clean chemistry
One environmental issue currently facing the semiconductor industry is the emission of perfluorinated compounds (PFCs) from a variety of processes including chamber cleaning following plasma enhanced chemical vapor deposition (PECVD) of dielectrics. The emission of PFCs has been targeted for reduction due to the contribution of these species to global warming. An option under investigation is the use of alternative compounds that emit lower amounts of global warming species. The current study presents chamber cleaning times and emissions from the use of one such species, trifluoroacetic anhydride (TFAA), in a widely used commercial PECVD tool, the Novellus Concept One 200. A central composite design-of-experiments was employed to calculate response surfaces for the chamber clean time and PFC emission concentrations as the chamber pressure, TFAA flow rate, and oxygen flow rate were varied. The chamber clean times were measured using optical emission spectroscopy, quadrupole mass spectrometry, as well as Fourier transform infrared (FTIR) spectroscopy, and the PFC emissions were quantified using FTIR spectroscopy. The performance of TFAA is compared to standard Novellus Concept One 200 C2F6 and C3F8 chamber cleaning processes and to processes in which the effect of augmentation of C2F6 with NF3 is studied.