We investigated the detection properties of nitrogen monoxide (NO) gas using transparent p-type CuAlO2 thin film gas sensors. The CuAlO2 film was fabricated on an indium tin oxide (ITO)/glass substrate by pulsed laser deposition (PLD), and then the transparent p-type CuAlO2 active layer was formed by annealing. Structural and optical characterizations revealed that the transparent p-type CuAlO2 layer with a thickness of around 200 nm had a non-crystalline structure, showing a quite flat surface and a high transparency above 65 % in the range of visible light. From the NO gas sensing measurements, it was found that the transparent p-type CuAlO2 thin film gas sensors exhibited the maximum sensitivity to NO gas in dry air at an operating temperature of 180˚C. We also found that these CuAlO2 thin film gas sensors showed reversible and reliable electrical resistance-response to NO gas in the operating temperature range. These results indicate that the transparent p-type semiconductor CuAlO2 thin films are very promising for application as sensing materials for gas sensors, in particular, various types of transparent p-n junction gas sensors. Also, these transparent p-type semiconductor CuAlO2 thin films could be combined with an n-type oxide semiconductor to fabricate p-n heterojunction oxide semiconductor gas sensors.

• 박수정(충남대학교 차세대전자기판회로학과) | Park, Soo-Jeong
• 김효진( 충남대학교 차세대전자기판회로학과, 충남대학교 공과대학 재료공학과) | 김효진
• 김도진( 충남대학교 차세대전자기판회로학과, 충남대학교 공과대학 재료공학과) | 김도진