Impedance Spectroscopy and Dielectric Relaxation in Phthalocyanine Thin Film

Abstract

Dielectric relaxation behavior of spin coated thin film of novel ball-type binuclear zinc(II) phthalocyanine were studied using impedance spectroscopy technique over a frequency range of 5–13x10⁶ Hz and temperatures (298 – 468 K). Simulation of the obtained impedance data indicated that the dielectric behaviour of the system can be modeled by a parallel RC electrical equivalent circuit. A frequency dependence in the form of ω^m, where the index m is found strongly temperature dependent, was observed for the ac conductivity σ_ac. Ac conductivity data were analyzed in terms two different models. The observed temperature dependence of the m indicate that the ac charge transport in Pc film take place via hopping process.

 

Keywords

• Phthalocyanine,Impedance,Relaxation,Ac conductivity,CBH model

FTALOSIYANIN İNCE FILMDE EMPEDANS SPEKTROSKOPI VE DIELEKTRIK DURULMA

Abstract

Döndürerek kaplama yöntemiyle hazırlanan top tipi çinko (II) ftalosiyanin ince filmlerin dielektrik durulma davranışları 5 Hz. ile 13x10⁶ Hz frekans aralığında sıcaklığa bağlı olarak (298 K – 468 K sıcaklık aralığında) empedans spektroskopi yöntemiyle incelenmiştir. Elde edilen verilerin modellenmesinde sistemin dielektrik davranışının paralel RC eşdeğer devre ile temsil edilebileceği görülmüştür. Filmlerde ac iletkenliğin frekansa bağlılığının ω^m şeklinde olduğu ve frekansın üssü olan m parametresinin kuvvetle sıcaklığa bağlı olduğu gözlemlenmiştir. Deneysel olarak elde edilen ac iletkenlik verileri iki farklı model kullanılarak analiz edilmiştir. Frekansın üssü olan m parametresinin sıcaklığa bağlılığının incelenmesinde çinko (II) ftalosiyanin ince filmlerde ac yük iletiminin hoplama mekanizması sayesinde gerçekleştiği sonucuna varılmıştır.

Keywords

• Ftalosiyanin,Empedans,Durulma,Ac iletkenlik,CBH model

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