Patent ID: 11867648
Assignee: FLUSSO LIMITED
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. A fluid sensor for sensing a concentration or composition of a fluid, the fluid sensor comprising:
a semiconductor substrate comprising a first etched portion and a second etched portion;
a dielectric region located on the semiconductor substrate, wherein the dielectric region comprises a first dielectric membrane located over the first etched portion of the semiconductor substrate, and a second dielectric membrane located over the second etched portion of the semiconductor substrate;
two temperature sensing elements on or within the first dielectric membrane and two temperature sensing elements on or within the second dielectric membrane; and
an output circuit configured to measure a differential signal between the two temperature sensing elements of the first dielectric membrane and the two temperature sensing elements of the second dielectric membrane;
wherein the first dielectric membrane is exposed to the fluid and the second dielectric membrane is isolated from the fluid; and
wherein one or both of the temperature sensing elements within the first and second dielectric membranes are configured to operate as heating elements.