Patent ID: 8431420

Claim:
A manufacturing method of an ultrasonic probe for forming an ultrasonic probe mounted with a semiconductor device, in which an element having an upper electrode mechanically operated when a potential difference is applied between the upper electrode and a lower electrode disposed via a cavity part serves as one cell, blocks each including a predetermined number of the cells disposed in a first direction and a second direction orthogonal to the first direction are provided on a main surface of a semiconductor substrate, the upper electrodes of the plurality of cells constituting the blocks disposed in the first direction are electrically connected to each other by spokes, the lower electrodes of the plurality of cells constituting the blocks disposed in the second direction are electrically connected to each other, and the blocks are disposed in a matrix in the first direction and the second direction, the manufacturing method comprising: (a) a step of measuring a breakdown voltage between the upper electrode and the lower electrode after operating the upper electrode; (b) a step of removing the upper electrode of the cell determined to be defective in the step (a); and (c) a step of forming a protective film on the main surface of the semiconductor substrate after the step (b).