US 12,455,255 B2
CMOS integrated humidity sensor with built-in heater
Yufei Wu, San Diego, CA (US); Abhijeet Paul, San Diego, CA (US); Ravi Pramod Kumar Vedula, San Diego, CA (US); Mishel Matloubian, San Diego, CA (US); Periannan Chidambaram, San Diego, CA (US); and Hyunchul Jung, San Diego, CA (US)
Assigned to QUALCOMM INCORPORATED, San Diego, CA (US)
Filed by QUALCOMM Incorporated, San Diego, CA (US)
Filed on Feb. 16, 2024, as Appl. No. 18/444,214.
Prior Publication US 2025/0264431 A1, Aug. 21, 2025
Int. Cl. G01N 27/22 (2006.01)
CPC G01N 27/223 (2013.01) [G01N 27/226 (2013.01); G01N 27/228 (2013.01)] 30 Claims
OG exemplary drawing
 
1. A complementary metal oxide semiconductor (CMOS) integrated humidity sensor, comprising:
a substrate; and
a plurality of unit humidity sensors disposed above the substrate, each unit humidity sensor comprising a resistive heating structure disposed above the substrate and a plurality of capacitive humidity sensors disposed above the resistive heating structure and set apart from each other in a vertical direction, each unit humidity sensor having a top surface that at least a portion of which is water-permeable,
wherein each capacitive humidity sensor comprises a pair of interdigitated vertical metal plates extending in a first direction, set apart from each other in a second direction orthogonal to the first direction, and separated from each other by a moisture-sensitive dielectric disposed between the pair of interdigitated vertical metal plates.