Semiconductor pressure sensor, pressure sensor apparatus, electronic equipment, and method of manufacturing semiconductor pressure sensor

摘要

A semiconductor pressure sensor (720) includes a thin film piezoelectric element (701) which applies strain to a portion of a semiconductor substrate that corresponds to a thin region (402). The thin film piezoelectric element (701) is formed at a distance away from diffusion resistors (406, 408, 410, and 412) functioning as strain gauges and is extended to the proximity of a bonding pad (716A) connected to an upper electrode layer of the thin film piezoelectric element and a bonding pad (716F) connected to a lower electrode thereof. The diffusion resistors (406, 408, 410, and 412) constitute a bridge circuit by metal wiring (722) and diffusion wiring (724). During self-diagnosis, a prescribed voltage is applied to a thin film piezoelectric element (701). If the output difference of the bridge circuit between before and after the voltage application falls outside a prescribed range, it is determined that a breakage occurs in the semiconductor pressure sensor (720).

主权项

1. A pressure sensor apparatus comprising:
a sensor configured to change a signal voltage based on a pressure; and a signal processing circuit for processing a signal output from said sensor, said signal processing circuit including
an amplification circuit for amplifying said signal voltage, anda first operation circuit for generating a first voltage changing in accordance with said pressure, based on an output voltage of said amplification circuit, wherein said first operation circuit is configured to generate said first voltage by subtracting a voltage having a prescribed correlation with said output voltage of said amplification circuit from a prescribed offset voltage.