The fabrication of quartz nano-pillars was investigated using dry etching with a Ni mask. The mask diameter increased during etching due to re-sputtering of the Pt/Cr seed layer. However, once the seed layer had been eroded the enlarged mask diameter did not increase any further. Hence, the use of the mask enabled the fabrication of nano-pillars with a high aspect ratio. In situ FTIR-ATR observation of HF quartz plate pressure bonding developed a new bonding technique involving the use of H2SiF6. The nano-pillar chips allowed then to size-separate DNA of 10 kbp and 38 kbp within 20 s. (c) 2006 Elsevier B.V. All rights reserved.