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arXiv · 2410.08372

Formation of Micrometer-Sized Textured Hexagonal Silicon Crystals via Nanoindentation

Mouad Bikerouin·Anna Marzegalli·Davide Spirito·Gerald J. K. Schaffar·Corrado Bongiorno·Fabrizio Rovaris·Mohamed Zaghloul·Agnieszka Anna Corley-Wiciak·Antonio M. Mio·Leo Miglio·Verena Maier-Kiener·Giovanni Capellini·Emilio Scalise
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Abstract

We present a comprehensive study on the formation of micrometer-sized, textured hexagonal diamond silicon (hd-Si) crystals via nanoindentation followed by annealing. Utilizing advanced characterization techniques such as polarized Raman spectroscopy, high-resolution transmission electron microscopy, and electron energy-loss spectroscopy, we demonstrate the successful transformation of silicon into high-quality hd-Si. The experimental results are further supported by first-principles calculations and molecular dynamics simulations. Notably, the hd-Si phase consists of nanometer-sized grains with slight misorientations, organized into large micrometer-scale textured domains. These findings underscore the potential of nanoindentation as a precise and versatile tool for inducing pressure-driven phase transformations, particularly for the stabilization of hexagonal silicon. The textured nature of hd-Si also presents a unique opportunity to tailor its optical properties, opening new avenues for its application in semiconductor and optoelectronic devices.

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Mouad Bikerouin, Anna Marzegalli, Davide Spirito, Gerald J. K. Schaffar, Corrado Bongiorno, Fabrizio Rovaris, Mohamed Zaghloul, Agnieszka Anna Corley-Wiciak, Antonio M. Mio, Leo Miglio, Verena Maier-Kiener, Giovanni Capellini, Emilio Scalise. 2024-10-10. Formation of Micrometer-Sized Textured Hexagonal Silicon Crystals via Nanoindentation. https://doi.org/10.1002/sstr.202400552

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