Capacitance/Conductance-Voltage-Frequency Characteristics of Au / PVC + TCNQ / p - Si Structures in Wide Frequency Range

• Published in: IEEE transactions on electron devices Vol. 61; no. 2; pp. 584 - 590
• Main Authors: Kaya, Ahmet, Tecimer, Huseyin, Vural, Ozkan, Tasdemir, Ibrahim Hudai, Altindal, Semsettin
• Format: Journal Article
• Language: English
• Published: 01-02-2014
• Subjects: Capacitance
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2013.2296037

The energy dependence of the interface states ( N ss ) and relaxation time ( tau ) and capture cross section ( sigma p ) of N ss in ( Au / PVC + TCNQ / p - Si ) heterojunction were investigated using high-low frequency capacitance ( C HF - C LF ) and conductance method, which contains many capacitance/conductance [ C / ( G / omega ) - V ] plots. The C value of the heterojunction increases with decreasing frequency as almost exponentially due to the existence of N ss between metal and semiconductor. The N ss and tau values have been obtained in the (0.053- E v )-(0.785- E v )-eV energy range by considering the voltage-dependent surface potential obtained from the lowest measurable frequency C - V curve at 1 kHz. The magnitude of N ss ranges from 3.88 10 12 ~ eV - 1 cm - 2 to 3.24 10 12 ~ eV - 1 cm - 2 . In the same energy range, the value of tau ranges from 5.73 10 - 5 to 1.58 10 - 4 ~ s and shows almost an exponential increase with increasing bias from the top of the valance band edge toward the midgap of semiconductor. The obtained N ss values from C HF - C LF and conductance methods are in good agreement with each other for the heterojunction. As a result, the mean value of N ss was found on the order of 10 12 ~ eV - 1 cm - 2 and this value is very suitable for an electronic device.