Electron-beam SAFIERTM process and its application for magnetic thin-film heads

We have coupled the SAFIERTM (shrink assist film for enhanced resolution) process with electron-beam lithography for the fabrication of the write top pole structures for thin-film heads. The SAFIERTM process is designed to physically shrink trench patterns and contact holes with very little deterioration of the resist profile. In this article, we will present the experimental results of the SAFIERTM process for the fabrication of the write top pole. We investigate the SAFIERTM process concerning several key processing issues, including shrink resolution capability, repetition of the SAFIERTM process, shrink-sensitive baking conditions, resist sidewall profile, and line edge roughness (LER) after shrinking of the trench. The experimental results show that this process not only shrinks the size of resist trenches and contact holes, but also improves LER and critical dimension variation. We demonstrate the capability of printing top pole structures with pole widths of sub-20 nm in a 0.30-mm-thick resist (aspect ratio.15:1), and electroplated top pole structures of 50 nm in a 0.50-mm-thick resist (aspect ratio=10:1). © 2004 American Vacuum Society. [DOI: 10.1116/1.1815309]