Comparison of ZnO, Al<sub>2</sub>O<sub>3</sub>, AlZnO, and Al<sub>2</sub>O<sub>3</sub>-Doped ZnO Sensing Membrane Applied in Electrolyte-Insulator-Semiconductor Structures
Chyuan-Haur Kao,
Yi-Wen Liu,
Chih-Chen Kuo,
Shih-Ming Chan,
Deng-Yi Wang,
Ya-Hsuan Lin,
Ming-Ling Lee,
Hsiang Chen
Affiliations
Chyuan-Haur Kao
Department of Electronic Engineering, Chang Gung University, 259 Wen-Hwa 1st Road, Kwei-Shan District, Taoyuan City 333, Taiwan
Yi-Wen Liu
Department of Electronic Engineering, Chang Gung University, 259 Wen-Hwa 1st Road, Kwei-Shan District, Taoyuan City 333, Taiwan
Chih-Chen Kuo
Department of Applied Materials and Optoelectronic Engineering, National Chi Nan University, No.1, University Rd., Puli 545, Taiwan
Shih-Ming Chan
Department of Applied Materials and Optoelectronic Engineering, National Chi Nan University, No.1, University Rd., Puli 545, Taiwan
Deng-Yi Wang
Department of Applied Materials and Optoelectronic Engineering, National Chi Nan University, No.1, University Rd., Puli 545, Taiwan
Ya-Hsuan Lin
Department of Applied Materials and Optoelectronic Engineering, National Chi Nan University, No.1, University Rd., Puli 545, Taiwan
Ming-Ling Lee
Department of Electro-Optical Engineering, Minghsin University of Science and Technology, No. 1, Xinxing Rd., Xinfeng 304, Taiwan
Hsiang Chen
Department of Applied Materials and Optoelectronic Engineering, National Chi Nan University, No.1, University Rd., Puli 545, Taiwan
In this study, ZnO, AlZnO, Al2O3, and Al2O3-doped ZnO-sensing membranes were fabricated in electrolyte–insulator–semiconductor (EIS) structures. Multiple material analyses indicate that annealing at an appropriate temperature of 500 °C could enhance crystallizations, passivate defects, and facilitate grainizations. Owing to their material properties, both the pH-sensing capability and overall reliability were optimized for these four types of membranes. The results also revealed that higher Al amounts increased the surface roughness values and enhanced larger crystals and grains. Higher Al compositions resulted in higher sensitivity, linearity, and stability in the membrane.
