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arXiv · 2306.13648

Spatially resolved dielectric loss at the Si/SiO$_2$ interface

Megan Cowie·Taylor J. Z. Stock·Procopios C. Constantinou·Neil Curson·Peter Grütter
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Abstract

The Si/SiO$_2$ interface is populated by isolated trap states which modify its electronic properties. These traps are of critical interest for the development of semiconductor-based quantum sensors and computers, as well as nanoelectronic devices. Here, we study the electric susceptibility of the Si/SiO$_2$ interface with nm spatial resolution using frequency-modulated atomic force microscopy to measure a patterned dopant delta-layer buried 2 nm beneath the silicon native oxide interface. We show that surface charge organization timescales, which range from 1-150 ns, increase significantly around interfacial states. We conclude that dielectric loss under time-varying gate biases at MHz and sub-MHz frequencies in metal-insulator-semiconductor capacitor device architectures is highly spatially heterogeneous over nm length scales. Supplemental GIFs can be found at https://doi.org/10.6084/m9.figshare.25546687

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Megan Cowie, Taylor J. Z. Stock, Procopios C. Constantinou, Neil Curson, Peter Grütter. 2023-06-23. Spatially resolved dielectric loss at the Si/SiO$_2$ interface. https://arxiv.org/abs/2306.13648

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