著者

Kimura Yoshinari Kitamura Masatoshi Kitani Asahi Arakawa Yasuhiko

出版者

Institute of Physics

雑誌

Jpn. J. Appl. Phys. (ISSN:00214922)

巻号頁・発行日

vol.55, no.2, 2016-01-22

被引用文献数

3

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Pentacene-based organic thin-film transistors (TFTs) having a SiO<inf>2</inf>gate dielectric treated with oxygen plasma have been investigated for control of the threshold voltage. The threshold voltage changed in the wide range from −15 to 80 V, depending on plasma treatment time, AC power for plasma generation, and gate dielectric thickness. The threshold voltage change was attributed to negative charges induced on and/or near the surface of the gate dielectric. The threshold voltage change on the order of 1 V was particularly proportional to plasma treatment time. The predictable change enables the control of threshold voltage in this range. In addition, the effect of gate bias stress on threshold voltage was examined. The results suggested that gate bias stress does not negate the threshold voltage change induced by plasma treatment.

著者

Tatara Shingo Kuzumoto Yasutaka Kitamura Masatoshi

出版者

Institute of Physics

雑誌

Jpn. J. Appl. Phys. (ISSN:00214922)

巻号頁・発行日

vol.55, no.3, 2016-01-15

被引用文献数

19

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The surface properties, including work function and wettability, of Au and Ag surfaces modified with various substituted benzenethiols have been investigated. Whereas the work functions of the modified Au surfaces ranged from 4.42 to 5.48 eV, those of the modified Ag surfaces ranged from 3.99 to 5.77 eV. The highest work function of 5.77 eV was obtained on the Ag surface modified with pentafluorobenzenethiol, and the lowest work function of 3.99 eV was obtained on the Ag surface modified with 4-methylbenzenethiol. The water contact angle on modified Au surfaces was found to be in a wide range from 30.9 to 88.3°. The water contact angle on the Au surface modified with a substituted benzenethiol was close to that on the Ag surface modified with the same benzenethiol. Furthermore, the tension of the modified Au surfaces was estimated from their contact angles of water and ethylene glycol.

著者

Kitani Asahi Kimura Yoshinari Kitamura Masatoshi Arakawa Yasuhiko

出版者

Institute of Physics

雑誌

Jpn. J. Appl. Phys. (ISSN:00214922)

巻号頁・発行日

vol.55, no.3, 2016-01-07

被引用文献数

9

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The threshold voltage in p-channel organic thin-film transistors (TFTs) having dinaphthothienothiophene as a channel material has been investigated toward their applicability to logic circuits. Oxygen plasma treatment of the gate dielectric surface was carried out to control the threshold voltage. The threshold voltage changed in the range from −6.4 to 9.4 V, depending on plasma treatment time and the thickness of the gate dielectric. The surface charge after plasma treatment was estimated from the dependence of the threshold voltage. Operation of logic inverters consisting of TFTs with different threshold voltages was demonstrated as an application of TFTs with controlled threshold voltage.