著者

Park Wug-Dong Tanioka Kenkichi

出版者

Published by the Japan Society of Applied Physics through the Institute of Pure and Applied Physics

雑誌

Jpn J Appl Phys (ISSN:00214922)

巻号頁・発行日

vol.48, no.4, pp.04C159-04C159-4, 2009-04-25

被引用文献数

4

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The thickness dependence of the avalanche characteristics of a tellurium (Te)-doped amorphous selenium (a-Se) high-gain avalanche rushing amorphous photoconductor (HARP) target is investigated. To improve the quantum efficiency of the a-Se HARP photoconductive target, a Te-doped a-Se photoconductive layer is sandwiched within a-Se HARP target. The avalanche multiplication factor and hole ionization coefficient of the a-Se HARP target are obtained using the result of photocurrent measurement. The multiplication factor in the avalanche mode exponentially increases with increasing electric field by avalanche multiplication phenomena over the threshold field. The quantum efficiency of the 8-μm-thick a-Se HARP target in the avalanche mode is higher than that of the thin HARP target below 2 μm thickness. Also the spectral response, decay lag, and light-transfer characteristics are studied.

著者

Park Wug-Dong Tanioka Kenkichi

出版者

Published by the Japan Society of Applied Physics through the Institute of Pure and Applied Physics

雑誌

Japanese journal of applied physics. Pt. 1, Regular papers & short notes (ISSN:00214922)

巻号頁・発行日

vol.42, no.4, pp.1954-1956, 2003-04-15

被引用文献数

11

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In this paper, spectral responses of Te-doped a-Se HARP (High-gain Avalanche Rushing amorphous Photoconductor) thin films for a solid state image sensor have been reported. Te concentrations of Te-doped layer in a-Se HARP thin film were 15 wt.% and 26 wt.%, and thicknesses of Te-doped layer were 60 nm, 90 nm, and 120 nm. Spectral responses of Te-doped a-Se HARP films were investigated at bias voltages of 40 V and 60 V. Relative sensitivity and quantum efficiency of a-Se HARP films at 60 V were found to be improved by the increase of Te-doped layer thickness. This improvement is explained by the increased photogeneration efficiency at long wavelength region by the increase of Te-doped layer thickness and avalanche multiplication of the photogenerated carriers at a high electric field.