Sensitivity Change in Piezoelectric Ultrasonic Microsensors Caused by a Variation of Diaphragm Structures

다국어 초록 (Multilingual Abstract)

Sensitivity changes in piezoelectric-type ultrasonic microsensors have been investigated for
variations in the layered structures in their diaphragms. The structure variations have been
designed for sensitivity improvement in sensors having statically downward-deflected diaphragms
to reduce lateral strain cancellation on their piezoelectric layer by enhancing the strain of the
structural expansion component and by suppressing the strain of the bending component. The
piezoelectric layer on the front side of the diaphragm has been removed around the top electrode to
make slits with various widths. Silicon-dioxide and silicon layers on the rear side of the diaphragm
have been removed entirely. These two variations in the structures have been analyzed for their
effectiveness in sensitivity improvement, the modified sensor structures have been fabricated, and
their sensitivity have been evaluated.

다국어 초록 (Multilingual Abstract)

Sensitivity changes in piezoelectric-type ultrasonic microsensors have been investigated for
variations in the layered structures in their diaphragms. The structure variations have been
designed for sensitivity improvement in sensors having statically downward-deflected diaphragms
to reduce lateral strain cancellation on their piezoelectric layer by enhancing the strain of the
structural expansion component and by suppressing the strain of the bending component. The
piezoelectric layer on the front side of the diaphragm has been removed around the top electrode to
make slits with various widths. Silicon-dioxide and silicon layers on the rear side of the diaphragm
have been removed entirely. These two variations in the structures have been analyzed for their
effectiveness in sensitivity improvement, the modified sensor structures have been fabricated, and
their sensitivity have been evaluated.

참고문헌 (Reference)

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