US 12,235,232 B2
Gas sensor, method of manufacturing gas sensor, and fuel cell vehicle
Satoru Ito, Hyogo (JP); Kazunari Homma, Gifu (JP); Koichi Kawashima, Kyoto (JP); Koji Katayama, Nara (JP); and Shinichi Yoneda, Kyoto (JP)
Assigned to NUVOTON TECHNOLOGY CORPORATION JAPAN, Kyoto (JP)
Filed by Nuvoton Technology Corporation Japan, Kyoto (JP)
Filed on Aug. 27, 2021, as Appl. No. 17/459,262.
Application 17/459,262 is a continuation of application No. PCT/JP2020/000803, filed on Jan. 14, 2020.
Claims priority of application No. 2019-042012 (JP), filed on Mar. 7, 2019.
Prior Publication US 2021/0389264 A1, Dec. 16, 2021
Int. Cl. G01N 27/12 (2006.01); B60K 15/03 (2006.01); B60L 50/70 (2019.01)
CPC G01N 27/12 (2013.01) [B60K 15/03006 (2013.01); B60L 50/70 (2019.02); B60K 2015/03315 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A gas sensor, comprising:
a gas detecting element that includes a first electrode, a metal oxide layer provided on the first electrode, and a second electrode provided on the metal oxide layer, the gas detecting element detecting a gas molecule existing in a gas and including a hydrogen atom; and
a first insulating film having an opening that allows a part of the second electrode to be exposed therethrough, the first insulating film covering the first electrode, the metal oxide layer, and another part of the second electrode, wherein
the metal oxide layer has a characteristic in which a resistance value of the metal oxide layer changes when the second electrode comes into contact with the gas molecule,
a first step is provided at a portion lying on an interface between the metal oxide layer and the second electrode and located within the opening as viewed in plan view,
a local region is provided in the metal oxide layer and close to the first step,
a degree of oxygen deficiency of the local region is greater than a degree of oxygen deficiency of a region other than the local region in the metal oxide layer, and
in the plan view, the first electrode is larger than the first step.