Poly(p-xylylene) or parylene has been around for more than a half a century. It is typically deposited by the Gorham method from [2.2] paracyclophane. However, another method is via alpha-derivatives of p-xylene. Both poly(a-bromo-p-xylylene) and poly(a-chloro-p-xylylene) have been successfully deposited by this route through predominately HBr or HCl dehydrohalogenation gas-phase reactions. In the study reported here we synthesize a,a,a-tribromo-p-xylene and a-bromo-a′,a′-dichlorop-xylene as CVD precursors to yield a,a-and a,a′-dihalogenated poly(p-xylylene)s to try to convert them, via post-deposition annealing, to poly(phenylene ethynylene) (PPE). PPE and its intermediate poly(phenylene vinylene) (PPV), have potentially better thermal and oxidative properties, and in addition they are both photoluminescent. The as-deposited and annealed thin films have been characterized by Rutherford backscattering spectrometry (RBS), infrared spectroscopy, and UV-vis spectrophotometry, and electrically tested by dielectric constant, bias-temperature stress (BTS), and leakage current. It is found that the thin films crystallizes concurrent with the formation of PPV and possibly converts to PPE but has much residual chlorine and bromine. However, PPV exhibits excellent stability in contact with copper and is more thermally stable than poly(p-xylylene).
Ta family has been used as barrier to prevent Cu diffusion into interlayer dielectric in IC applications. Recent experiments demonstrated a more severe flatband voltage shift (ΔVFB) occurred for Ta/porous low k dielectrics/Si capacitors compared to that of Cu/porous low k dielectrics/Si capacitors after a moderate bias temperature stress (BTS). The flatband voltage shift under BTS was interpreted as the penetration of Ta ions into porous low k dielectrics. However, this interpretation has been under debate. In this paper, by using Secondary Ion Mass Spectrometry (SIMS) backside sputter depth profile technique, we report a direct evidence of Ta ions inside porous methyl silsesquioxane (MSQ) in a Ta/MSQ/Si structure after BTS.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.