Generation of metal photomasks by dip-pen nanolithography

The challenge of using DPN (dip-pen nanolithography) and associated chemistry to make photomasks of chromium on quartz and evaluate their utility as masters to prepare microelectrode arrays by conventional photolithography, was investigated. 1D pen arrays were coated with ODT by thermal evaporation and PEG by tip dipping in 5mg ml 1 PEG acetonitrile solution for 30s. All DPN-patterning experiments were carried out undercontrolled humidity and temperature. The Au films were etched for 10 mm with aqueous etching solution containing 20mm thiourea, 30mm iron nitrate, 20mm hydrochloric acid, and 2mm 1 octanol. All photolithography experiments were carried out with a mask aligner and positive-type photoresist. It was concluded that the numbers of photomasks can be increased through the use of arrays with larger number of pens, or through the use of contact printing-PN hybrid technique known as polymer-pen lithography.