Polymers for microlithographic applications: New directions and challenges

Advances in the fabrication technologies associated with electronic devices have placed increasing demands on microlithography, the technology used to generate today's integrated circuits. Within the next few years, a new for m of lithography will be required that routinely produces features of less than 0.1 mum. As the exposing wavelength of light decreases to facilitate h igher resolution imaging, the opacity of traditional materials precludes th eir use; and major research efforts to develop alternate materials are unde rway. As a current example, lithography tools utilizing 193 nm light are no w being introduced into the manufacturing environment. Through understandin g of materials structure and its relationship to device process requirement s and performance, a new class of cyclo-olefin based polymers was designed for these applications. In particular, alicyclic monomers such as norbornen e are readily copolymerized with maleic anhydride and substituted acrylates to afford a wide range of alternative matrices that exhibit transparency a t the exposing wavelength and aqueous base solubility. Materials properties must be carefully tailored to maximize lithographic performance with minim al sacrifice of other performance attributes. Further reduction in exposing wavelength to 157 nm introduces new challenges in polymer materials design . Efforts to address those challenges will be discussed.