Polypyrrole and poly(3,4-ethylenedioxythiophene) on silicon cantilever: Role of formation potential in bending displacement

Abstract

The feasibility of conducting polymer bending actuators deposited on free-standing conductive silicon cantilevers was studied in this work. The motivation is the micro-system-technique, where mostly silicon bimorph piezoelectric actuators have been applied. Polypyrrole (PPy) and poly(3,4-ethylenedioxythiophene) (PEDOT) with various formation potentials were studied. The formation potential 1.1 V was found optimal for both materials, while PEDOT outperformed PPy in virtually every aspect. Long-term durability tests of 1000 cycles showed that activity was maintained, with PEDOT holding up better than PPy. The results show that conducting polymers, especially PEDOT, could be viable active materials for Si-based bilayer actuators, with low driving voltages to reach significant displacements.