ABSTRACT CTS-9708944 Nealy, Paul F. U of Wisconsin, Madison The proposal's short-term research goal is to demonstrate the enabling technology for the resist system described below. This proposal for a Small Grants for Exploratory Research supports the investigation of the interfacial phenomena that govern the ordering of thin films of amphiphilic block copolymers on patterned hydrophobic/hydrophilic surfaces. Optical lithography, the most widespread technique for the fabrication of microelectronic devices, is approaching the lower limit (>100 nm) in the size of features that it can produce. At the same time, there is little doubt that the need for denser, faster and more powerful circuits will continue. Smaller features (50nm) can be produced with electron beam writing or stylus lithography. These processes, however, are currently serial and will require significant development for high-volume commercial applications. Lithographies based on shorter wavelength radiation, for example extreme ultra violet (EUV) and X-ray lithography (XRL), have the required resolution. but no satisfactory resist materials exist for applications below 100 nm. Current resist systems rely on kinetic processes such as diffusion and dissolution. The principles that govern these systems cannot be blindly extrapolated in the nanometer regime because of vanishing small tolerances and margins. New resist systems for the nanometer regime must be able to produce features of molecular dimensions with tolerances and margins of atomic dimensions. The proposed long -term research goal is to develop a nanofabrication technique based on interfacial phenomena and two levels of molecular: self-assembled monolayers (SAMs) and ordering of thin films of block because it leads to equilibrium structures that are at (or close to) thermodynamic minimum. Self-assembled monolayers (SAMs) will be formed on the surface of a substrate, and the SAMs will patterned in the plane of the amphiphilic block copolymer will be depos ited on the substrate, and surface energy will govern the ordering of the strongly segregating copolymer upon annealing. If the dimensions of the patterned SAMs are of the same order of magnitude as the dimensions of the polymer molecules, then structure in the polymer film will be induced normal to the substrate. Regions of low surface energy will be covered with the hydrophobic block of the polymer, and regions of high surface energy will be covered with the hydrophilic block of the polymer. It is expected that the order to propagate will pass through the entire thickness of the deposited film. One of the blocks of the block copolymer will be selectively etched. Arbitrarily shaped patterns with lateral dimensions of tens of nanometers will be transferred from the patterned SAMs to resist material (the remaining block of the copolymer) at the resolution of X-ray lithography.
