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Updated: Jan 23, 2026

Silicon Metal-oxide-semiconductor Quantum Dots for Single-electron Pumping
Published on: June 3, 2015
Fabrication and characterization of a ZnO quantum dots-based metal-semiconductor-metal sensor for hydrogen gas
Smrity Ratan1, Chandan Kumar1, Amit Kumar1
1Department of Electronics Engineering, Indian Institute of Technology (BHU), Varanasi, 221005, India.
Abstract:
This paper reports an interdigitated metal-semiconductor-metal (MSM) based hydrogen gas (H2) sensor using colloidal zinc oxide (ZnO) quantum dots (QDs) as the sensing material. The active layer is obtained by spin coating of as-synthesized colloidal ZnO QDs on a SiO2/Si substrate in which the SiO2 layer is grown by oxidation of the Si substrate. The surface morphology of a ZnO QDs -based active film is measured using scanning electron microscopy (SEM) and atomic force microscopy (AFM) support for enhanced gas response. The change in current is measured for different concentrations of H2 gas at 175 °C in an ambient air atmosphere. Reasonably good gas responses of ∼41% for 1% H2 gas and 83.2% for 4% H2 gas have been obtained in ambient air condition. A high selectivity of the proposed sensor with respect to ammonia, sulfur dioxide and organic vapours such as acetone, methanol, chlorobenzene, and chloroform has also been achieved due to nanostructure ZnO films.
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