Analysis of AC conductivity and dielectric relaxation of solution grown PVA film in desired frequency and temperature window

Organic interfacial layers as nanodielectrics and their thin films have become an interesting topic of research due to their application in flexible electronic devices that may offer a more energy efficient, eco-friendly and affordable approach to grow our electronic world. In our work Dielectric relaxation and ac conductivity (σ_ac) behaviour of solution grown Polyvinyl Alcohol (PVA) film has been investigated in the frequency range 100Hz to 1Mhz for three temperatures (20 °C, 30 °C, 40 °C) using capacitance-voltage (C-V) and conductance-voltage (G/ω-V) measurements. X-ray diffraction (XRD) has been used to investigate the structural properties and that confirms semi-crystalline nature of the film. Surface morphology evolution of the film has been done using Scanning Electron Microscopy (SEM). Sandwich structure of the type Ag-PVA-Ag was formed to study the dielectric and electrical properties of PVA films. Experimental results show that dielectric loss values were strong function of frequency and temperature. From ac conduction studies it was confirmed that ionic hoping is the main mechanism responsible for conduction. The imaginary part of electric modulus gives two peaks corresponding to relaxation dynamics. In addition, loss tangent and real part of electric modulus were obtained and analysed.