著者

宇佐美 清章 坂本 謙二 荒谷 毅 潮田 資勝

出版者

一般社団法人 日本液晶学会

雑誌

日本液晶学会討論会講演予稿集 (ISSN:18803490)

巻号頁・発行日

vol.1999, pp.6-7, 1999

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We have measured the polarized infrared (IR) absorption spectra of poly[4,4'-oxydiphenylen-l,2,3,4- cyclobutanetetracarboxyimide] (CBDA-ODA) films irradiated with linearly polarized ultraviolet light (LPUVL) of wavelength 〜 250 nm. The measurement was carried out for a very thin film (10 nm thick) as a function of the LPUVL exposure. The dichroic difference, A_⊥- A_//, of the phenyl C-C stretching vibration of CBDA-ODA, which is polarized along the polyimide chain, has a maximum around 3 J/cm^2. Here A_//and A_⊥ are the absorbance for the IR light polarized parallel and perpendicular to the polarization direction of LPUVL, respectively. The dichroic difference per unit film thickness at 3 J/cm^2 was greater than that of a rubbed CBDA-ODA film with the same film thickness. Although the average IR absorbance, (A_⊥+ A_//)/2, decreases monotonically over the entire measurement range of LPUVL exposure, A_⊥ increases up to 1 J/cm^2. This result shows that the number of polyimide molecules oriented perpendicular to the polarization direction of LPUVL increases. We conclude that the photo-induced orientation contributes to the large surface anisotropy of LPUVL-exposed CBDA-ODA films in addition to the anisotropic photo-induced decomposition.

著者

上原 洋一 潮田 資勝

出版者

一般社団法人 日本真空学会

雑誌

Journal of the Vacuum Society of Japan (ISSN:18822398)

巻号頁・発行日

vol.51, no.12, pp.796-800, 2008 (Released:2009-01-15)

参考文献数

21

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Scanning tunneling microscope (STM) light emission spectroscopy provides a powerful tool for characterization of individual nanometer scale structures on solid surfaces. However, the light to be detected is usually very weak. It is desirable to improve the intensity level for measurements with good signal-to-noise ratio. For this purpose the role that the STM tip-sample gap plays in the light emission is analyzed by the dielectric theory of STM light emission. Based on the theoretical predictions, we discuss how one can obtain strong STM light emission and problems associated with the enhancement of emission.

著者

潮田 資勝

雑誌

ぶんせき (ISSN:03862178)

巻号頁・発行日

no.374, 2006-02-05