A Novel Resonant-Frequency-Trimming Method Using CNT Rope Synthesis

We report a novel passive frequency-trimming method for microelectromechanical system (MEMS) resonators using carbon nanotube (CNT) rope synthesis on the side of the MEMS resonator. The method has a number of advantages over conventional methods, including low cost, reduced processing time, and greater applicability. First, the method requires only an ac voltage source and a dispersed CNT suspension to synthesize CNT ropes using dielectrophoresis. The method can be implemented in <;3 min at room temperature and atmospheric pressure. The resonant frequency of the MEMS resonator can be shifted by 0.5%-24%. In addition, the method can restore the original frequency by cutting the CNT ropes by passing a current through them, so that trimming can be carried out repeatedly by connecting and disconnecting the CNT ropes until the desired frequency is achieved.