| Title: | High-Resolution p-Type Metal Oxide Semiconductor Nanowire Array as an Ultrasensitive Sensor for Volatile Organic Compounds |
| Author(s): | Cho SY; Yoo HW; Kim JY; Jung WB; Jin ML; Kim JS; Jeon HJ; Jung HT; |
| Address: | "Department of Chemical and Biomolecular Engineering (BK-21 Plus), Korea Advanced Institute of Science and Technology (KAIST) , Yuseong-gu, Daejeon 305-701, Korea. KAIST Institute for Nanocentury , Yuseong-gu, Daejeon 305-701, Korea. The Fourth R&D Institute, Agency for Defense Development , Yuseong-gu, Daejeon 305-600, Korea. Department of Nano-Structured Materials Research, Korea National Nanofab Center , Yuseong-gu, Daejeon 305-701, Korea" |
| DOI: | 10.1021/acs.nanolett.6b01713 |
| ISSN/ISBN: | 1530-6992 (Electronic) 1530-6984 (Linking) |
| Abstract: | "The development of high-performance volatile organic compound (VOC) sensor based on a p-type metal oxide semiconductor (MOS) is one of the important topics in gas sensor research because of its unique sensing characteristics, namely, rapid recovery kinetics, low temperature dependence, high humidity or thermal stability, and high potential for p-n junction applications. Despite intensive efforts made in this area, the applications of such sensors are hindered because of drawbacks related to the low sensitivity and slow response or long recovery time of p-type MOSs. In this study, the VOC sensing performance of a p-type MOS was significantly enhanced by forming a patterned p-type polycrystalline MOS with an ultrathin, high-aspect-ratio ( approximately 25) structure ( approximately 14 nm thickness) composed of ultrasmall grains ( approximately 5 nm size). A high-resolution polycrystalline p-type MOS nanowire array with a grain size of approximately 5 nm was fabricated by secondary sputtering via Ar(+) bombardment. Various p-type nanowire arrays of CuO, NiO, and Cr2O3 were easily fabricated by simply changing the sputtering material. The VOC sensor thus fabricated exhibited higher sensitivity (DeltaR/Ra = 30 at 1 ppm hexane using NiO channels), as well as faster response or shorter recovery time ( approximately 30 s) than that of previously reported p-type MOS sensors. This result is attributed to the high resolution and small grain size of p-type MOSs, which lead to overlap of fully charged zones; as a result, electrical properties are predominantly determined by surface states. Our new approach may be used as a route for producing high-resolution MOSs with particle sizes of approximately 5 nm within a highly ordered, tall nanowire array structure" |
| Keywords: | gas sensor high resolution lithography nanopattern p-Type metal oxide volatile organic compound; |
| Notes: | "PubMed-not-MEDLINECho, Soo-Yeon Yoo, Hae-Wook Kim, Ju Ye Jung, Woo-Bin Jin, Ming Liang Kim, Jong-Seon Jeon, Hwan-Jin Jung, Hee-Tae eng Research Support, Non-U.S. Gov't 2016/06/16 Nano Lett. 2016 Jul 13; 16(7):4508-15. doi: 10.1021/acs.nanolett.6b01713. Epub 2016 Jun 17" |
