Resistive MEMS humidity sensor

摘要

A semiconductor device includes a substrate, an insulating film provided on a surface of the substrate, and a sensing film formed of a conductive material deposited on top of the insulating film. The sensing film defines at least one conductive path between a first position and a second position on the insulating film. A first circuit connection is electrically connected to the sensing film at the first position on the insulating layer, and a second circuit connection is electrically connected to the sensing film at the second position. A control circuit is operatively connected to the first circuit connection and the second circuit connection for measuring an electrical resistance of the sensing film. The sensing film has a thickness that enables a resistivity of the sensing film to be altered predictably in a manner that is dependent on ambient moisture content.

主权项

1. A semiconductor device comprising:
a substrate; an insulating film formed of a dielectric material and provided on a surface of the substrate; a sensing film formed of a conductive material deposited on top of the insulating film, the sensing film defining at least one conductive path between a first position and a second position on the insulating film; a first circuit connection electrically connected to the sensing film at the first position on the insulating layer; a second circuit connection electrically connected to the sensing film at the second position; and a control circuit operatively connected to the first circuit connection and the second circuit connection and configured to measure an electrical resistance of the sensing film, wherein the sensing film has a thickness that enables a resistivity of the sensing film to be altered predictably in a manner that is dependent on ambient moisture content, and wherein the control circuit is configured to pass a reset pulse through the sensing film via the first and the second circuit connections, the reset pulse being configured to heat the sensing film to a degree that causes water molecules to be desorbed from the sensing film.