title: Highly Sensitive H2S Sensor Based on the Metal-Catalyzed SnO2 Nanocolumns Fabricated by Glancing Angle Deposition.
abstract: As highly sensitive H2S gas sensors, Au- and Ag-catalyzed SnO2 thin films with morphology-controlled nanostructures were fabricated by using e-beam evaporation in combination with the glancing angle deposition (GAD) technique. After annealing at 500 °C for 40 h, the sensors showed a polycrystalline phase with a porous, tilted columnar nanostructure. The gas sensitivities (S = Rgas/Rair) of Au and Ag-catalyzed SnO2 sensors fabricated by the GAD process were 0.009 and 0.015, respectively, under 5 ppm H2S at 300 °C, and the 90% response time was approximately 5 s. These sensors showed excellent sensitivities compared with the SnO2 thin film sensors that were deposited normally (glancing angle = 0°, S = 0.48).
authors.affiliation: Department of Materials Science and Engineering, University of Seoul, 163, Seoulsiripdae-ro, Dongdaemun-gu, Seoul 130-743, Korea. ksyoo@uos.ac.kr.
authors.forename: Kwang Soo
authors.initials: KS
authors.lastname: Yoo
authors.affiliation: Center for Electronic Materials, Korea Institute of Science and Technology, 5, Hwarang-ro 14-gil, Seongbuk-gu, Seoul 136-791, Korea. 113341@kist.re.kr.|KU-KIST Graduate School of Converging Science and Technology, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 136-701, Korea. 113341@kist.re.kr.
authors.forename: Soo Deok
authors.initials: SD
authors.lastname: Han
authors.affiliation: Center for Electronic Materials, Korea Institute of Science and Technology, 5, Hwarang-ro 14-gil, Seongbuk-gu, Seoul 136-791, Korea. moonhigyu@gmail.com.
authors.forename: Hi Gyu
authors.initials: HG
authors.lastname: Moon
authors.affiliation: Center for Electronic Materials, Korea Institute of Science and Technology, 5, Hwarang-ro 14-gil, Seongbuk-gu, Seoul 136-791, Korea. sjyoon@kist.re.kr.
authors.forename: Seok-Jin
authors.initials: SJ
authors.lastname: Yoon
authors.affiliation: Center for Electronic Materials, Korea Institute of Science and Technology, 5, Hwarang-ro 14-gil, Seongbuk-gu, Seoul 136-791, Korea. cykang@kist.re.kr.|KU-KIST Graduate School of Converging Science and Technology, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 136-701, Korea. cykang@kist.re.kr.
authors.forename: Chong-Yun
authors.initials: CY
authors.lastname: Kang
keywords: H2S sensor; SnO2 nanocolumn; glancing angle deposition; nanosensor