Fabrication of porous ZnO thin films using wet chemical etching with 0.5% HNO₃

Abstract

Purpose

The purpose of this paper is to synthesize porous zinc oxide (ZnO) by means of strain etching/wet chemical etching method with the use of 0.5% of nitric acid (HNO₃) etchant. The structural and surface morphological properties of the samples are accessed by using X‐ray diffraction (XRD) and scanning electron microscopy (SEM) characterization techniques.

Design/methodology/approach

ZnO samples used in this work were deposited on the p‐Si (111) substrates by using radio frequency (RF) sputtering technique. Wet chemical etching processes with the use of 0.5% HNO₃ etchant was applied on these samples in order to obtain porous structure. The porous ZnO samples are characterized by means of XRD and SEM to access their structural and surface morphological properties.

Findings

The XRD and SEM cross‐sectional measurements revealed that the thickness of the etched ZnO thin films is proportional to the etching time. SEM micrographs show that the surface morphology of ZnO changes over etching time. On the other hand, XRD results indicate that the crystallite sizes of the ZnO(002) decreases when the etching time increases.

Originality/value

The paper shows how porous ZnO thin films have been successfully synthesized by using simple wet chemical etching. SEM images reveal that this method is reliable when producing porous structure ZnO surfaces.

Citation

Chai Im, A., Lu Tze Jian, L., Poh Kok, O., Yaakob, S., Chin Guan, C., Sha Shiong, N., Hassan, Z., Abu Hassan, H. and Johar Abdullah, M. (2012), "Fabrication of porous ZnO thin films using wet chemical etching with 0.5% HNO₃", Microelectronics International, Vol. 29 No. 2, pp. 96-100. https://doi.org/10.1108/13565361211237699