다양한 기판에서 성장한 탄소 나노튜브 특성연구

Abstract

Porous silicon has tremendous exposed surface area; thus the area allows it to enhance light absorption and chemical activity of the suspended material in the pores. The textured wafer, consisted of a large number of pyramidal structures on the surface, also increases the properties. 3-D suspended Single Walled carbon Nanotubes (SWNTs) show great properties such as chemical, physical and photonic. This is because, as the SWNTs are separated each naontubes, the SWNTs own properties could be expressed. We synthesized the SWNTs network on the diverse surface morphology by LP-TCVD method and proved SWNTs existed by Raman spectroscopy. SWNTs could absorb the Infra red (IR) region based on their diameter. The SWNTs having under 5nm diameter specifically satisfy this region. The SWNTs grown in the pores with the small diameter have prospective viewing for a Photo detector, especially IR. Here, we repot a novel type of the IR detector s using the suspended SWNTs. Previous IR detectors using the SWNTs showed the disadvantages, low sensitivity and slow response time as a photo sensor. We measured the response time and photo current of the SWNTs for IR radiation. This new type detector suggested the clue for SWNTs to be applied as one of photo sensor without the problems. Hydrophobic property is important because of the application, like biosensor or covering material. Fundamentally, SWNTs express the contact angle over the 90 degrees that is hydrophobic. However, it is impossible for SWNTs to allow over 150 degrees, super hydrophobic, on flat substrate morphology. We tremendous enhanced the hydrophobic property using the other substrate morphology. The textured wafer basically possesses micro structures and SWNTs are nano structures, combining of which brings about the super hydrophobic properties. This is because the wafer with SWNTs is similar to Lotus leaf that water droplet cannot be placed. Following the statement supports this phenomenon. The water droplet is difficult to be placed the top point of the pyramidal structure, then the water droplet move to SWNTs but the SWNTs? surface are not stable neither. We measured the field emission of SWNTs grown on the various substrates morphology. The SWNTs on the substrates were influenced by surface morphology during the synthesis process. The different beta value, which is closed with aspect ratio, is one of evidence. The precursors for SWNTs used to be aggregated but this tendency can be prevented by the morphology. Therefore, SWNTs conformation is totally different, which brings about different values.