A Reduced-Temperature Process for Preparing Atomically Clean Si(100) and SiGe(100) Surfaces with Vapor HF

Peña, Luis Fabián [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); University of New South Wales, Sydney, NSW (Australia)]; Anderson, Evan M. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000237713085); Mudrick, John P. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)]; Rosenberg, Samantha G. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Lockheed Martin Space, Palo Alto, CA (United States)]; Scrymgeour, David A. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000185709841); Bussmann, Ezra [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)]; Misra, Shashank [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)]

doi:10.1021/acs.jpcc.5c00280

DOE OSTI · 2566655

A Reduced-Temperature Process for Preparing Atomically Clean Si(100) and SiGe(100) Surfaces with Vapor HF

Peña, Luis Fabián [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); University of New South Wales, Sydney, NSW (Australia)]·Anderson, Evan M. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000237713085)·Mudrick, John P. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)]·Rosenberg, Samantha G. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Lockheed Martin Space, Palo Alto, CA (United States)]·Scrymgeour, David A. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000185709841)·Bussmann, Ezra [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)]·Misra, Shashank [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)]

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Abstract

Silicon processing techniques such as atomic precision advanced manufacturing (APAM) and epitaxial growth require surface preparations that activate oxide desorption (typically >1000 °C) and promote surface reconstruction toward atomically clean, flat, and ordered Si(100)-2 × 1. Here, in this study, we compare the aqueous and vapor phase cleaning of Si and Si/SiGe surfaces to prepare APAM-ready and epitaxy-ready surfaces at lower temperatures. Angle resolved X-ray photoelectron spectroscopy (ARXPS) and Fourier transform infrared (FTIR) spectroscopy indicate that vapor hydrogen fluoride (VHF) cleans dramatically reduce carbon surface contamination and allow the chemically prepared surface to reconstruct at lower temperatures, 600 °C for Si and 580 °C for a Si/Si 0.7 Ge 0.3 heterostructure, into an ordered atomic terrace structure indicated by scanning tunneling microscopy (STM). After thermal treatment and vacuum hydrogen termination, we demonstrate STM hydrogen desorption lithography (HDL) on VHF-treated Si samples, creating reactive zones that enable area-selective chemistry by using a thermal budget similar to CMOS process flows. We anticipate that these results will establish new pathways to integrate APAM with Si foundry processing.

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Peña, Luis Fabián [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); University of New South Wales, Sydney, NSW (Australia)], Anderson, Evan M. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000237713085), Mudrick, John P. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)], Rosenberg, Samantha G. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Lockheed Martin Space, Palo Alto, CA (United States)], Scrymgeour, David A. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000185709841), Bussmann, Ezra [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)], Misra, Shashank [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)]. 2025-05-06. A Reduced-Temperature Process for Preparing Atomically Clean Si(100) and SiGe(100) Surfaces with Vapor HF. https://doi.org/10.1021/acs.jpcc.5c00280

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