Feasibility Study of Cochlear-like Acoustic Sensor using PMN-PT Single Crystal Cantilever Array
S. Hur, S.Q. Lee, W.D. Kim
Korea Institute of Machnery & Materials, KR
acoustic, PMN-PT, cantilever, sensor
The mammalian cochlea is an organ that performs the conversion of the incoming mechanical energy into electrical signals in the auditory nerve fibers. Current cochlear Implants have been developed in an effort to restore sensorineural hearing loss of patient. But it consumes large electric power due to complex electronic circuit device. In this paper, we have studied the feasibility of use of PMN-PT((1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3) single-crystal piezoelectric cantilever array as an alternative of conventional cochlear implant. The PMN-PT material has been shown to possess piezoelectric coefficients and electro-mechanical coupling responses significantly larger than conventional ceramics. We have fabricated piezoelectric PMN-PT cantilever array which has the cantilever size of the width of 200 um and the thickness of 10um. The length of cantilever was adjusted with a parameter of resonance frequency. Resonance frequency of PMN-PT cantilevers was measured with laser interferometer and charge sensitivity was measured with charge measuring device. PMN-PT cantilever array was exposed with sound pressure of specific frequency corresponding to resonance frequency and sensitivity of sound pressure was measured. The experimental results show that the PMN-PT cantilever array exhibits high sensitivity. This implies that the single crystal PMN-PT cantilever array has a potential candidate as cochlear like acoustic sensor.
Nanotech 2008 Conference Program Abstract