| 摘要 |
<p>PURPOSE:To form a small-sized sensor which can obtain an image by being inserted into a minute part such as a blood vessel, etc., by connecting a thin film piezoelectric converting part and a signal processing circuit part of the piezoelectric converting part concerned by a pattern wiring in the extreme vicinity of the piezoelectric converting part and installing them on a semiconductor substrate. CONSTITUTION:On a silicon substrate 10, a circuit part 15 consisting of a driver circuit for exciting a piezoelectric thin film, a pre-amplifying circuit, a transmission/reception separating circuit, etc., is formed. Thereafter, an ultrasonic converting part is constituted by forming first the lower electrode 11 consisting of, for instance, platinum, etc., and laminating successively a thin film 12 of 10mum film thickness mainly composed of lead titanate, and also, the upper electrode 13 consisting of aluminum. The thin film 12 mainly composed of lead titanate is formed by a high frequency magnetron spattering method. After the upper electrode 13 is formed, a sample is held at 150 deg.C, a voltage of 100V is applied between the upper and the lower electrodes 11, 13 for ten minutes, and a polarization processing is performed.</p> |
