Pitch reduction lithography by pressure-assisted selective wetting and thermal reflow

[Display omitted] ► We present a new pitch reduction lithographic technique by selective wetting. ► A meniscus was exploited to reduce the feature size of original line pattern. ► The line width was controllable by concentration and ashing time. ► The pattern shape was reconfigurable under different reflow conditions. We report on a new pitch reduction lithographic technique by utilizing pressure-assisted selective wetting and thermal reflow. The primary line-and-space pattern of low molecular weight polystyrene (PS) (Mw=17,300) was formed by solvent-assisted capillary force lithography (CFL), on which a diluted photoresist (PR) solution was selectively filled into the spaces by the application of a slight pressure (200gcm−2). Subsequent removal of the PS pattern by toluene and ashing process led to a line pattern with approximately 50% pitch reduction. It was observed that the size reduction and space to width ratios were controllable by changing PR concentration and ashing time.