Radiation-induced polarization and charge transport mechanisms in graphene-doped PVA based MPS structures
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING, cilt.132, sa.8, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 132 Sayı: 8
- Basım Tarihi: 2026
- Doi Numarası: 10.1007/s00339-026-09965-6
- Dergi Adı: APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Aerospace Database, Chemical Abstracts Core, Chimica, Compendex, INSPEC, Academic Search Ultimate (EBSCO), Engineering Source (EBSCO), Materials Science & Engineering Collection (ProQuest), Technology Collection (ProQuest)
- Gazi Üniversitesi Adresli: Evet
Özet
In this work, capacitance-voltage (C-V) and conductance-voltage (G/omega-V) measurements were performed in a dark environment, both before and after beta irradiation, at a frequency of 1 MHz over a broad voltage range (- 4 V < V < 3 V), to determine the dielectric parameters of the Au/(3% graphene-doped PVA)/n-Si (MPS) structure. Based on these measurements, dielectric parameters of the MPS structure including the dielectric constant (epsilon '), dielectric loss (epsilon ''), loss tangent (tan delta), ac electrical conductivity (sigma(ac)), the real and imaginary parts of the electric modulus (M ' and M ''), the real and imaginary components of impedance (Z ' and Z ''), and the phase angle (theta) were determined both before and after beta irradiation. The obtained results were analyzed through comparison with previously reported studies in the literature. Variations, in the form of increases or decreases, were observed in the calculated dielectric parameters as a consequence of beta radiation. This behavior arises because, upon beta irradiation of the MPS structure, charge carriers are transferred to radiation-induced lattice defects at the interface and to interface states formed within the forbidden energy band gap of the semiconductor. These defect centers and interface states subsequently function as recombination centers for charge carriers, leading to increases or decreases in carrier polarization. Furthermore, the Cole-Cole plot of M ' versus M '' exhibited a semicircular arc. The appearance of this arc indicates that the polarization mechanism within the interfacial layer is predominantly governed by grain effects rather than grain boundary contributions. The dielectric constant (epsilon ') of the 3% Graphene doped PVA (0.03 Gr: PVA) insulator in the MPS structure was determined to be approximately 408 at 1 kHz. As this value is nearly 107x times higher than that of conventional SiO2 (epsilon '(SiO2)= 3.8), it was concluded that this material can be effectively utilized as an alternative to traditional insulating layers for storing a greater amount of electrical charge and energy.