Shakil Ahmed Jiskani

2Department of Electrical Engineering, Sukkur IBA University, Sukkur, Sindh, Pakistan

Safdar Ali Abro

3Department of Mechanical Engineering Technology, The Benazir Bhutto Shaheed University of Technology and Skill Development Khairpur Mirs, Sindh, Pakistan

Abdul Shakoor Shaikh

4Department of Electronic Engineering, Mehran University of Engineering and Technology SZAB Campus Khairpur Mirs, Sindh, Pakistan

Kaneez Fatima

5Department of Electronic Engineering,Mehran University of Engineering and Technology SZAB Campus Khairpur Mirs, Sindh, Pakistan

Ghulam E Mustafa Abro

6Research Unit for Robophilosophy and Integrative Social Robotics (RISR), Aarhus University, Aarhus C 8000, Denmark

Madad Ali Shah

2Department of Electrical Engineering, Sukkur IBA University, Sukkur, Sindh, Pakistan

ABSTRACT:

Humidity and moisture sensors play important roles in industrial process control, environmental monitoring, aerospace, pharmaceutical manufacturing, energy infrastructure and semiconductor fabrication applications. The properties of the humidity-sensitive dielectric layer are important to the performance of these sensors. Anodic Spark Deposition (ASD) is one of the special fabrication techniques to obtain a highly porous and chemically stable α-Al₂O₃ film, which is found to be useful for the fabrication of high-performance moisture sensor. ASD is a technique that allows for direct electrochemical oxidation to create porous ceramic coatings on substrates (graphite, glass, titanium, aluminum and so on) under spark discharge conditions. The α-Al₂O₃ films formed have good thermal stability, corrosion resistance and mechanical strength, and control of pore structure. This article provides a summary of the principles of ASD, pore formation mechanism, process parameters and the resulting microstructural characteristics. Special focus on application of porous alumina produced from ASD in capacitive humidity and moisture sensor. The effects of pore size distribution, surface morphology, adsorption/desorption kinetics, response speed, sensitivity and long-term stability are included. Hybrid α-Al₂O₃/SiO₂ dielectric structures are also reviewed recently.

Keywords: Anodic Spark Deposition, Alpha Alumina, Humidity, Moisture Sensor, Porous Ceramics

How to Cite this paper?

This work is licensed under a Creative Commons Attribution 4.0 International License.