Electron-beam lithography has been widely applied to define critical features in magnetic recording thin-film heads. To be a viable resist candidate for read sensor fabrication, e-beam resists need to be optimized in three major aspects-resolution, etching resistance, and strippability. Here the authors investigated four typical resists for their applicability in the production of sub-50 nm read sensors and extendibility into sub-30 nm regime, including a negative-tone chemically amplified resist (CAR), a negative-tone non-CAR, a positive-tone CAR, and a positive-tone non-CAR. Pattern design for positive-/negative-tone resists, resist resolution capability, sloped resist pole profile, underlayer preparation for Si-containing imaging layer, hybrid lithography for low-sensitivity non-CARs, and process issues in ion-beam etching of sensor stacks are discussed in detail. Finally, 20 nm giant magnetoresistive sensor fabrication was demonstrated. (c) 2006 American Vacuum Society.