Inkjet-printed graphene Hall mobility measurements and low-frequency noise characterization

Abstract

We report room temperature Hall mobility measurements, low temperature magnetoresistance analysis and low-frequency noise characterization of inkjet-printed graphene films on fused quartz and SiO₂/Si substrates. We found that thermal annealing in vacuum at 450 °C is a necessary step in order to stabilize the Hall voltage across the devices, allowing their electrical characterization. The printed films present a minimum sheet resistance of 23.3 Ω sq^-1 after annealing, and are n-type doped, with carrier concentrations in the low 10²⁰ cm^-3 range. The charge carrier mobility is found to increase with increasing film thickness, reaching a maximum value of 33 cm² V^-1 s^-1 for a 480 nm-thick film printed on SiO₂/Si. Low-frequency noise characterization shows a 1/f noise behavior and a Hooge parameter in the range of 0.1-1. These results represent the first in-depth electrical and noise characterization of transport in inkjet-printed graphene films, able to provide physical insights on the mechanisms at play.