• Bulletin of the Korean Chemical Society
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• v.24 no.8
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• pp.1155-1162
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• 2003

Nanocrystalline semiconductor film electrodes have been prepared by sintering three different sizes of TiO₂ nanoparticle sols on conducting indium-tin-oxide (ITO) glass substrate. The electrochemical and photoelectrochemical properties of the prepared electrodes were comparatively investigated. The particle sizes, surface morphologies and crystallinities of the films were studied by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. Cyclic voltammetry and capacitance measurements in the dark implies the formation of depletion layer in the semiconductor films which was usually neglected in the previous studies and shows that flat band potential ($E_{fb}$

• Electrical & Electronic Materials
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• v.7 no.1
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• pp.7-14
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• 1994

Structural and optical characteristics in $SnO_2$/a-Se/Al sample by aging variation and applying constant voltage had been investigated. a-Se was varied with monoclinic structure and its surface was greatly exchanged. Its capacitance was first decreased and then increased and its photo-current, photo-voltage and photo-capacitance were increased gradually with day and applying voltage. From the results, crystallization of a-Se and dopant trap level formation had been identified. Also, it was acknowledged $SnO_2$/a-Se/Al sample is useful in photovoltaic and solid thin film cell.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.32 no.6
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• pp.199-204
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• 1983

In this paper, we investigated that the Al-Amorphous Se-Al structure had a large photovoltage and a Dark EMF (DEMF). This DEMF phenomena did not show just after the fabrication of a sample. However, it was shown after a few days, and it was increased with time, and was saturated after 30 days. Just after the fabrication of a sample, by appling the positive voltage on a sample for 100mins, we observed almost the same effect as had shown in a aging experiment. As the results, we found that Al3+ ions has related to a DEMF by migrating into amorphous Se, and form a trap in amorphous Se. We have also observed the photocapacitance effect to identify this trap formation.