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arXiv · 1204.4461

Quantum Size Effects on the Chemical Sensing Performance of Two-Dimensional Semiconductors

Junghyo Nah·S. Bala Kumar·Hui Fang·Yu-Ze Chen·Elena Plis·Yu-Lun Chueh·Sanjay Krishna·Jing Guo·Ali Javey
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Abstract

We investigate the role of quantum confinement on the performance of gas sensors based on two-dimensional InAs membranes. Pd-decorated InAs membranes configured as H2 sensors are shown to exhibit strong thickness dependence, with ~100x enhancement in the sensor response as the thickness is reduced from 48 to 8 nm. Through detailed experiments and modeling, the thickness scaling trend is attributed to the quantization of electrons which favorably alters both the position and the transport properties of charge carriers; thus making them more susceptible to surface phenomena.

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Junghyo Nah, S. Bala Kumar, Hui Fang, Yu-Ze Chen, Elena Plis, Yu-Lun Chueh, Sanjay Krishna, Jing Guo, Ali Javey. 2012-04-19. Quantum Size Effects on the Chemical Sensing Performance of Two-Dimensional Semiconductors. https://doi.org/10.1021/jp300446z

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