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arXiv · 2607.16439

Atomically precise triple-step staircase on a vicinal silicon surface: Is it Si(5 5 7), Si(7 7 10) or Si(8 8 11)?

A. N. Chaika·A. Yu. Aladyshkin·V. N. Semenov·A. S. Aladyshkina·A. M. Ionov·S. I. Bozhko
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Abstract

Scanning tunneling microscopy studies of periodic arrays of triple steps fabricated on single-crystalline Si(5 5 7) wafers demonstrate several possible atomic structures of consecutive steps and Si(1 1 1) terraces maintaining the same periodicity on micrometer-sized surface areas. Detailed analysis of the atomically resolved data reveals the formation of Si(8 8 11) triple-step staircase with a period of 18b=5.99 nm in projection onto the terrace plane, where b=0.333 nm is the distance between atomic rows for the Si(1 1 1)1x1 surface. Schematic models for several possible configurations of either 7x7 or 5x5-reconstructed terraces and triple steps are proposed.

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A. N. Chaika, A. Yu. Aladyshkin, V. N. Semenov, A. S. Aladyshkina, A. M. Ionov, S. I. Bozhko. 2026-07-17. Atomically precise triple-step staircase on a vicinal silicon surface: Is it Si(5 5 7), Si(7 7 10) or Si(8 8 11)?. https://arxiv.org/abs/2607.16439

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