Local wettability modification by thermochemical nanolithography with write-read-overwrite capability

The wettability of a thin polymer film was modified twice by thermochemical nanolithography. By means of a first local chemical modification induced by an atomic force microscope tip heated to $110±20°C$⁠, hydrophilic patterns are written over an originally hydrophobic polymer surface. By further heating to $190±20°C$⁠, a second chemical modification reverses the local wettability change introduced by the first chemical modification. This write-read-overwrite capability can be particularly useful in the design of complex nanofluidic devices.