Preparatıon Of The Mps Structures And The Investıgatıon Of Dıelectrıc Propertıes As A Functıon Of Frequency And Voltage

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Thesis Type: Postgraduate

Institution Of The Thesis: Gazi Üniversitesi, Fen Bilimleri Enstitüsü, Turkey

Approval Date: 2020

Thesis Language: Turkish

Student: SEDA KARADAŞ

Supervisor: MUZAFFER BALBAŞI

Abstract:

Real and the imaginary components of complex dielectric (*=’-j’’), complex electric modulus (M*=M’+jM’’), and electrical conductivity (ac) of the fabricated Al/(0.05Graphene-PVA)/p-Si/Al (MPS) structures were investigated in the wide frequency (5kHz-5MHz) and voltage (± 4V) range by using impedance (Z=1/Y=G+jC) measurements at room temperature. To get more storage charges/energy in capacitor, highdielectric (0.05Gr-PVA) organic interfacial layer was grown between Al and p-Si by electrospinning method. We observed that capacitance of MPSis considerably increased by using this interlayer. The value of ’ was changed from 32.586 (at 5 kHz) to 1.132 (at 5 MHz). The decreases in ’ and ” with increasing frequency was attributed to the existence surface/dipole polarization and surface states (Nss). The observed lower-values of M' at lowfrequencies is related to a long-range mobility of charge carriers. On the other hand, the observed peak in the tanδ-V and M’’-V plots and changes their magnitude and position with frequency because of at low frequencies, dipoles have enough time to orient themselves in the direction of the alternating field contrary to high frequency. Additionally, we show that organic interlayer can be successfully used instead of insulator in respect of its flexibility, low-energy consumption, and easy grown processes