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Title: Transparent conductor-Si pillars heterojunction photodetector

Abstract

We report a high-performing heterojunction photodetector by enhanced surface effects. Periodically, patterned Si substrates were used to enlarge the photo-reactive regions and yield proportionally improved photo-responses. An optically transparent indium-tin-oxide (ITO) was deposited on a Si substrate and spontaneously formed an ITO/Si heterojunction. Due to an electrical conductive ITO film, ITO/Si heterojunction device can be operated at zero-bias, which effectively suppresses the dark current, resulting in better performances than those by a positive or a negative bias operation. This zero-bias operating heterojunction device exhibits a short response time (∼ 22.5 ms) due to the physical reaction to the incident light. We revealed that the location of the space charge region (SCR) is crucial for a specific photon-wavelength response. The SCR space has the highest collection efficiency of the photo-generated carriers. The photo-response can be maximized when we design the photodetector by superposing the SCR space over a corresponding photon-absorption length. The surface enhanced Si pillar devices significantly improved the photo-responses ratios from that of a planar Si device. According to this design scheme, a high photo-response ratio of 5560% was achieved at a wavelength of 600 nm. This surfaced-enhanced heterojunction design scheme would be a promising approach for various photoelectric applications.

Authors:
 [1];  [2];  [1];  [3]
  1. Department of Electrical Engineering, Incheon National University, Incheon 406772 (Korea, Republic of)
  2. (United States)
  3. Measurement and Analysis Division, National Nanofab Center (NNFC), Daejeon 305-806 (Korea, Republic of)
Publication Date:
OSTI Identifier:
22314631
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 6; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ABSORPTION; DESIGN; EQUIPMENT; HETEROJUNCTIONS; LENGTH; PERIODICITY; PHOTONS; SPACE CHARGE; SUBSTRATES; SURFACES; TIN OXIDES; VISIBLE RADIATION; WAVELENGTHS

Citation Formats

Yun, Ju-Hyung, Department of Electrical Engineering, University at Buffalo, State University of New York, Buffalo, New York 14260, Kim, Joondong, E-mail: joonkim@incheon.ac.kr, and Park, Yun Chang. Transparent conductor-Si pillars heterojunction photodetector. United States: N. p., 2014. Web. doi:10.1063/1.4892489.
Yun, Ju-Hyung, Department of Electrical Engineering, University at Buffalo, State University of New York, Buffalo, New York 14260, Kim, Joondong, E-mail: joonkim@incheon.ac.kr, & Park, Yun Chang. Transparent conductor-Si pillars heterojunction photodetector. United States. doi:10.1063/1.4892489.
Yun, Ju-Hyung, Department of Electrical Engineering, University at Buffalo, State University of New York, Buffalo, New York 14260, Kim, Joondong, E-mail: joonkim@incheon.ac.kr, and Park, Yun Chang. Thu . "Transparent conductor-Si pillars heterojunction photodetector". United States. doi:10.1063/1.4892489.
@article{osti_22314631,
title = {Transparent conductor-Si pillars heterojunction photodetector},
author = {Yun, Ju-Hyung and Department of Electrical Engineering, University at Buffalo, State University of New York, Buffalo, New York 14260 and Kim, Joondong, E-mail: joonkim@incheon.ac.kr and Park, Yun Chang},
abstractNote = {We report a high-performing heterojunction photodetector by enhanced surface effects. Periodically, patterned Si substrates were used to enlarge the photo-reactive regions and yield proportionally improved photo-responses. An optically transparent indium-tin-oxide (ITO) was deposited on a Si substrate and spontaneously formed an ITO/Si heterojunction. Due to an electrical conductive ITO film, ITO/Si heterojunction device can be operated at zero-bias, which effectively suppresses the dark current, resulting in better performances than those by a positive or a negative bias operation. This zero-bias operating heterojunction device exhibits a short response time (∼ 22.5 ms) due to the physical reaction to the incident light. We revealed that the location of the space charge region (SCR) is crucial for a specific photon-wavelength response. The SCR space has the highest collection efficiency of the photo-generated carriers. The photo-response can be maximized when we design the photodetector by superposing the SCR space over a corresponding photon-absorption length. The surface enhanced Si pillar devices significantly improved the photo-responses ratios from that of a planar Si device. According to this design scheme, a high photo-response ratio of 5560% was achieved at a wavelength of 600 nm. This surfaced-enhanced heterojunction design scheme would be a promising approach for various photoelectric applications.},
doi = {10.1063/1.4892489},
journal = {Journal of Applied Physics},
number = 6,
volume = 116,
place = {United States},
year = {Thu Aug 14 00:00:00 EDT 2014},
month = {Thu Aug 14 00:00:00 EDT 2014}
}
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