Electrical and Thermal Property of Si/GaAs Heterojunction Formed by Ultra-Thin Oxide Interfacial Layer

Md Nazmul Hasan; Yixiong Zheng; Junyu Lai; Edward Swinnich; Olivia Grace Licata; Mohadeseh A. Baboli; Baishakhi Mazumder; Parsian K. Mohseni; Jung-Hun Seo

arXiv · 2107.06983

Electrical and Thermal Property of Si/GaAs Heterojunction Formed by Ultra-Thin Oxide Interfacial Layer

Md Nazmul Hasan·Yixiong Zheng·Junyu Lai·Edward Swinnich·Olivia Grace Licata·Mohadeseh A. Baboli·Baishakhi Mazumder·Parsian K. Mohseni·Jung-Hun Seo

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Abstract

We have successfully demonstrated Si/GaAs p-n heterostructures using Al2O3 ultra-thin oxide interfacial layers. The band diagram and band offsets were investigated using X-ray photoelectron spectroscopy and confirm a small discontinuity in the conduction band (0.03 eV) at the interface. The interface defect density (Dit) values of the heterointerface with different ultra-thin oxide (UO) thicknesses ranged from 0.35 nm to 3.5 nm and were also characterized based on a metal-oxide-semiconductor capacitor (MOSCAP) structure using a capacitance-voltage measurement. The results revealed that a thin UO interfacial layer (around 1 nm) maximizes carrier transport property due to better surface passivation and efficient tunneling properties. Thermal property investigation also shows that the Al2O3 UO interfacial layer offers a good tunneling layer but also facilitates phonon transport across the interface. Finally, the electrical characterization of Si/GaAs heterojunction p-n diodes confirms reliable rectifying behavior with an extremely low ideality factor; thus, heterogeneous integration using the UO approach offers a robust way to create more types of heterojunctions between dissimilar semiconductors.

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Md Nazmul Hasan, Yixiong Zheng, Junyu Lai, Edward Swinnich, Olivia Grace Licata, Mohadeseh A. Baboli, Baishakhi Mazumder, Parsian K. Mohseni, Jung-Hun Seo. 2021-07-14. Electrical and Thermal Property of Si/GaAs Heterojunction Formed by Ultra-Thin Oxide Interfacial Layer. https://arxiv.org/abs/2107.06983

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