The effect of temperature and relative humidity on patterning of a ferroelectric polymer P(VDF-TrFE) via dip-pen nanolithography

This paper reports the effect of temperature and relative humidity on the patterning of a ferroelectric polymer poly(vinylidene fluoride-trifluorethylene) [P(VDF-TrFE 80:20)] onto a gold substrate via dip-pen nanolithography (DPN). It is found that temperature plays a significant role in this system, that the transport rate of P(VDF-TrFE) increases as the temperature increases, and that the diffusion length increases linearly with the square root of time at all of the measured temperatures. A critical temperature of 55°C is observed, above which, the transport rate of P(VDF-TrFE) increases significantly, and the interaction forces between the probe tip and P(VDF-TrFE) and between P(VDF-TrFE) and the gold substrate decrease. It is suggested that a phase transition at about 55°C may have happened in the thin film of P(VDF-TrFE). The influence of relative humidity on the transport rate of the hydrophobic P(VDF-TrFE) is small.