ÉTude préliminaire des propriétés microlithographiques d'une résine renfermant un polyimide et un bis‐azide sensible aux UV lointains

Abstract

&SUME:L'Ctude prkliminaire des propriCtCs microlithographiques des rCsines obtenues en mClangeant un polyimide et un bis-azide a pennis de montrer que de telles rCsines pourraient probablement Ctre utilisCes en tant que resines microlithographiques sensibles aux UV lointains. En effet ces rCsines donnent des couchages homogbnes qui ont des Cpaisseurs convenables. De plus, elles sont trbs sensibles aux irradiations: elles subissent alors des modifications de structure lorsqu'on les irradie par des radiations de longueur d'onde Cgale ? i 254 nm. Les parties ainsi insolCes sont insolubles dans les solvants constituCs par des melanges d'eau et de dioxane ou d'eau et de 1 -N-mCthylpyrrolidone alors que ces mCmes solvants solubilisent parties non in-solCes. SUMMARY.A preliminary study of the microlithographic properties of resins obtained by mixing a polyimide with a bis-azide has shown the possibility to be used in the far UV.The solutions of the resins are easily processed to give films with a good control of the thickness. Moreover, the films obtained are sensitive to UV irradiation at 254 nm. The irradiated parts are insoluble in a mixture of solvents constituted of water and dioxane or water and 1 -N-methylpyrrolidone, whereas the non-irradiated regions are soluble in these solvent mixtures.Les resines photosensibles sont celles qui sont le plus utiliskes en microlithographie. Parmi elles, on trouve celles qui absorbent dans 1'UV proche (320 nm c h c 400 nm). Cependant la photolithographie dans le proche UV

Anionic Polymerization of n-Butyl Cyanoacrylate in Emulsion and Miniemulsion

“…It is not possible to check whether the cyanoacetate molecule is formed in excess, since data obtained from current DCI mass spectrometry analyses are not quantitative. However, simple chain-end degradation (Scheme a) is supported by different information from the literature (ref of this paper and references therein): (i) all poly(alkyl cyanoacrylate) chains possess an hydroxymethylene end-group (anionic polymerization of alkyl cyanoacrylate is initiated by an hydroxide anion); (ii) the chain-ends, rather than internal bonds, were invoked as the degradation site; (iii) the content of released formaldehyde is generally low.…”

“…4 These properties make cyanoacrylate monomers powerful instant glues for various adhesive applications. 5,6 Polymerization of alkyl cyanoacrylates is also known to arise in excess water (for a comprehensive review on the subject, see ref 7). Couvreur first developed in 1979 a process to directly generate nanoparticles from methyl or ethyl cyanoacrylates.…”

“…Traces of weak bases, including water, initiate their polymerizations, and chain termination occurs only in the presence of strong acids or superacids . These properties make cyanoacrylate monomers powerful instant glues for various adhesive applications. , …”