Somdatta Paul

Investigation of the electrical switching and rectification characteristics of a single standalone n-type ZnO-nanowire/p-Si junction diode

In this work, n-ZnO-nanowire/p-Si junction diodes have been fabricated and characterized both physically as well as electrically. The measurements are performed on a single standalone nanowire diode for the investigation of electrical transport through the nano-junction. The rectification properties of the single n-ZnO nanowire/p-Si diode have been studied for various input waveforms and frequencies. The diodes exhibit very promising rectification as well as switching behavior with no charge storage effect and consequently, a switching time as small as ∼1 ms has been achieved.

Investigating the Growth-Time Dependent Comparative Performance of Vapour-Liquid-Solid (VLS) Grown p-CuO/n-Si Thin Film Hetero-Junction Solar Cells

This work investigates the impact of growth time on the performance of p-CuO/n-Si hetero-junction solar cells, where CuO thin films are grown by employing vapour liquid solid method, using CBD synthesized CuO powder. Studies are performed in terms of the film morphology, chemical composition, crystallite structure, optical properties and energy conversion efficiency. The potential for photovoltaic applications of such films are investigated by measuring the p-CuO/n-Si diode current-voltage characteristics and by extracting its relevant photovoltaic parameters, including open circuit photo-generated voltage, short circuit current density and energy conversion efficiency.

Electrical Characterization of n-ZnO NW/p-CuO Thin Film Hetero-Junction Solar Cell Grown by Chemical Bath Deposition and Vapor Liquid Solid Technique with Varying Reaction Time

The current work reports the fabrication of p-CuO/n-ZnO heterojunction grown on n-Silicon (100) substrate by varying the growth time of ZnO nanowires. The p-CuO thin film has been grown by vapor-liquid-solid (VLS) technique and the n-ZnO nanowires by employing chemical bath deposition (CBD) method. The surface morphology, crystalline structure and optoelectronic properties of the heterojunction are investigated by employing SEM, XRD and spectroscopic ellipsometry respectively. The ZnO NWs grown for 40 min on the CuO film, indicates best performance in terms of crystal quality, band gap, refractive index and solar performance parameters like short circuit current density, open circuit voltage and efficiency.

Performance investigation of n-ZnO nanowire/p-CuO thin film heterojunction solar cell grown by chemical bath deposition and vapour liquid solid technique

In the present work, the authors report the fabrication of p-CuO/n-ZnO heterojunction grown on (100) n-Si substrate. The CuO thin film has been grown by employing vapour-liquid-solid (VLS) technique and the n-ZnO nanowires are grown by chemical bath deposition (CBD) method. The optoelectronic and the photovoltaic properties of the fabricated devices have been investigated. The heterojunction exhibits a photocurrent of 0.25µA under UV illumination of 13mW/cm2 at 365 nm. An open circuit voltage of 20mV, short-circuit current density of 7.7mA/cm2 and a fill factor of 23.3% is obtained from the heterojunction. The overall power conversion efficiency is 0.3%.