Ac electrical parameters of Al-ZnPc-Al organic semiconducting films

• Authors: Rushdi Kitaneh , Abdelkarim Saleh , Robert Gould
• Languages of publication: EN

Abstracts

EN

The ac electrical parameters of thermally evaporated zinc phthalocyanine, ZnPc, semiconducting thin films was measured in the temperature range of 180–390 K and frequency between 0.1 and 20 kHz. Aluminum electrode contacts were utilized to sandwich the organic ZnPc semiconducting films. Capacitance and loss tangent decreased rapidly with frequency at high temperatures, but at lower temperatures a weak variation is observed. An equivalent circuit model assuming ohmic contacts could qualitatively and successfully explains capacitance and loss tangent behavior.The ac conductivity showed strong dependence on both temperature and frequency depending on the relevant temperature and frequency range under consideration. Ac conductivity σ (ω) is found to vary with ω, as ω
s with the index s ≤ 1.35 suggesting a dominant hopping conduction process at low temperatures (< 250 K) and high frequency. The conductivity of some samples did not increase monotonically with temperature. This behavior was attributed to oxygen exhaustion of the sample as its temperature is increased. The ac conductivity behavior at low temperatures of ZnPc films could be described well by Elliott model assuming hopping of charge carriers between localized sites.

Keywords

EN

Thermal evaporation; organic semiconductor; capacitance; conductivity; ZnPc; 73.61-I; 68.55.-a; 72.20.-I; 78.30.Jw

• Publisher: De Gruyter Open
• Journal: Open Physics
• Year: 2006
• Volume: 4
• Issue: 1
• Pages: 87-104

Dates

published

1 - 3 - 2006

online

1 - 3 - 2006

Contributors

author

Rushdi Kitaneh

• Physics Department, College of Science and Technology, Al-Quds University, Jerusalem, P.O. Box 20002, West Bank, Palestine via, Israel

author

Abdelkarim Saleh

• Physics Department, College of Science and Technology, Al-Quds University, Jerusalem, P.O. Box 20002, West Bank, Palestine via, Israel

author

Robert Gould

• Thin Films Laboratory, Physics Department, Keele University, Keele, Staffordshire, ST5 5BG, UK

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Identifiers

DOI

10.1007/s11534-005-0008-4