SEMICONDUCTOR PRESSURE SENSOR

摘要

In a semiconductor pressure sensor element, a first hydrogen permeation protection film is provided on a principal surface side of a first silicon substrate, and a second hydrogen permeation protection film is provided on a principal surface side of a second silicon substrate. The permeation paths of the hydrogen fluxes shown by the arrows A and B in FIG. 9 are blocked by the films. Also, a trench surrounding a reference pressure chamber is provided, and the first hydrogen permeation protection film and a third hydrogen permeation protection film are joined at the bottom portion of the trench, thereby blocking the permeation path of the hydrogen flux shown by the arrow C in FIG. 9. Furthermore, by providing a hydrogen storage chamber, hydrogen is trapped before the hydrogen reaches the reference pressure chamber.

主权项

1. A semiconductor pressure sensor, comprising:
a first silicon substrate having a diaphragm; a first hydrogen permeation protection film provided on the side of one principal surface of the first silicon substrate; a second silicon substrate, one principal surface of which having a depressed portion is joined to another principal surface of the first silicon substrate via an embedded oxide film; and a reference pressure chamber, the space of which, enclosed by the depressed portion and the other principal surface of the first silicon substrate, is brought into a vacuum state.