The investigation of electrothermal response and reliability of flexible graphene micro-heaters

This study developed a flexible graphene micro-heater that can be used for high efficient temperature control and has outstanding long-term performance using ultrafast laser ablation. The input voltages (V), electrode widths (W), and electrode patterns (2–4 finger) were discussed to determine their effects on electrothermal response and switching performance of the micro-heaters. The experimental results confirmed the outstanding performance of the micro-heaters during on−off operation under varying input voltages. At W = 500 μm, time to steady state t_ss were less than 3 s for the input voltages from 10 V to 30 V under varying electrode patterns. The micro-heater exhibited a superior heating rate of 15.7 °C/s using ultrafast laser ablation. The experimental results revealed that the increasing rate of heater temperature with respect to input voltage increased as the number of electrode fingers decreased, especially under high input voltages. The thermal cycling and bending experiments revealed excellent temperature stability and durability (<1 °C) of the micro-heater. The present study showed that the flexible graphene micro-heater is a high efficient and a reliable device for heating applications using ultrafast laser ablations.