부산대학교 도서관

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.tsf.2004.08.076 Byline: In-Seop Lee (a), Chung-Nam Whang (a), Young-Hee Lee (b), Gun Hwan Lee (c), Bong-Joo Park (d), Jong-Chul Park (d), Won-Seon Seo (e), Fu-Zhai Cui (f) Keywords: Nano iridium oxide; E-beam evaporation; Charge injection; Cortical neural cell; Neurofilament Abstract: Iridium film with the thickness of 30 and 60 nm were formed on both Si wafer and commercially pure (CP) Ti by electron beam evaporation. The thin iridium film showed the identical charge injection capability with the bulk Ir. However, the charge injection value of iridium film was decreased with continuous potential cycling when the deposited iridium became depleted due to the formation of oxide. The number of cycles at which the charge injection value decreased was 800 and 1600 cycles for the 30- and 60-nm-thick Ir film, respectively. FE-SEM observations on the cross section of Ir film clearly showed the thicker iridium oxide was formed with the more potential cycling. Ar ion beam etching to substrates before deposition certainly improved the adhesion strength of Ir film enough to resist to the strain induced by the larger volume occupation of iridium oxide. Swiss 3T3 fibroblasts culture on Ir and Ir oxide showed no cytotoxicity. Also, embryonic cortical neural cell culture on electrode indicated neurons adhered and survived by the formation of neurofilament. Author Affiliation: (a) Institute of Physics and Applied Physics, and Yonsei Center for Nano Technology, Yonsei University, Seoul 120-749, Korea (b) Department of Rehabilitation Medicine, Yonsei University Wonju College of Medicine, Kangwon 220-701, Korea (c) Korea Institute of Machinery and Materials, Chang-Won 641-010, Korea (d) Department of Medical Engineering, Yonsei University College of Medicine, Seoul 120-752, Korea (e) Korea Institute of Ceramic Engineering and Technology, Seoul 153-023, Korea (f) Department of Materials Science and Engineering, Tsinghua University, Beijing 100084, China