Ferroelectric properties of III-V Semiconductors

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This document gives an approximate calculation of the frequency bandwidth of the MilliNewton – and serves as a starting point for calculations on other cantilever-type sensors. The mechanical resonance frequencies of MilliNewton are high, due to the very small cantilever size. The working frequency is in fact limited by the electrical circuit at ca. 1 kHz (MilliNewton-A) or ca. 200 Hz (MilliNewton-B).

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Size effect in ferroelectrics is treated as a competition between the geometrical symmetry of the ferroelectric sample and its crystalline symmetry. Polarization rotation is shown to be a clear finite size effect that results from this competition, which can be induced by all types of driving forces that are coupled with the sample geometry, such as electrical, mechanical and/or thermal. The concept is illustrated with the Landau theory analysis of the polarization state of a cylindrical nanowire of the pro

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Novel, highly sensitive piezoelectric acoustic sensors based on partially unclamped Pb(Zr-x, Ti1-x)O-3 (PZT) coated cantilever and bridge have been fabricated by silicon micromachining. High sensitivity at low frequencies (5-100 Hz) has been achieved by patterning very narrow slits (3 to 5 mum) around the structures. A typical response of 100 mV Pa-1 and a noise equivalent pressure of 1.6 mPa Hz(1/2) at 20 Hz have been measured using a 10 pF charge amplifier. Stress compensation, dry etching and integration

Ferroelectric properties of III-V Semiconductors

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