Impact of the limitations of state-of-the-art micro-fabrication processes on the performance of pillar array columns for liquid chromatography

► Pillar array columns with inter pillar distances down to 0.23 μm were fabricated. ► Micro-fabrication limitations were investigated by means of SEM. ► Column performance was compared for pillar array columns with different pillar sizes. ► The expected decrease in plate height was not observed.