Environnement Procéés Production » Présentée Et Soutenue Publiquement Par Materials and Anti-adhesive Issues in Uv-nil Chapter Iii. Application of Uv Curable Resists in a Reverse Uv-nil Process .... 99 Introduction

The UV curing nanoimprint lithography (UV-NIL) is a next generation lithography technique that canproduce very tiny patterns (in the nanometer scale) by a simple imprinting step performed with a patternedand transparent template in a flowable resist (deposed par spin-coating on a silicon substrate as thin layer).The imprinting step is then followed by UV exposure (that cures the resist) and demolding. Due to its highpotential in replicating patterns with high resolution, UV-NIL is considered nowadays as a possiblecandidate to perform the lithographic step in the next generation integrated circuits. Two critical issuesthreaten the spreading of UV-NIL at large scale: defects generated during imprinting step (depending onthe resist flowing behaviour) and short life-time of a treated mold (a fluorinated self assembled monolayer,F-SAM, is deposed on the mold surface to avoid the sticking of the resist). Concerning the first issue, amodel potentially capable to predict the flowing distance of liquid photo curable resist is presented.The experiments performed over the second issue were really profitable and gave interesting results. Infact, a better understanding on the mechanisms of ASL degradation was achieved. This aging is due to achemical attack (exerted by free radicals, which was generated into the uv curable resist duringpolymerization step, toward the fluorinated molecule, and conditioned as well by the chemical nature of theresist) and a mechanical degradation (caused by the stress exerted during demolding step and linked to thequality of F-SAM grafting on the mold surface). The add of fluorinated surfactants in the chemicalformulation of the resist represent an effective solution for improving the number of imprints performedemploying the same mold.At the end of this manuscript there is the presentation of a hybrid (organic-inorganic) resist, that wassynthesized for a real useful application: the creation of templates to arrange at large scale (fewmillimetres) di-bloc copolymers (sized of few nanometres) by graphoepitaxy.