@article{ref1,
title="Thermal instability and silicidation of ultrathin HfO x on Si(001)",
journal="Journal of the Korean Physical Society",
year="2004",
author="Lee, J.-h.",
volume="44",
number="6",
pages="1590-1593",
abstract="The thermal instability and silicidation behaviors of ultrathin HfO x on Si(001) were studied by using scanning tunneling microscopy (STM) with in-situ X-ray photoelectron spectroscopy (XPS). A 1.5-nm-thick HfO x layer was grown on Si(001) by using Hf deposition in an oxidizing ambient. In the low temperature (600 ∼ 800°C) region, hafnium oxide near the interface region easily reacted with the substrate silicon ions in order to form a silicate structure (Hf-O-Si bonding units). When the SiO evaporation proceeded in the high-temperature (≥ 900°C) region, silicon migration from the substrate became kinetically remarkable and transformed the Hf-O-Si units into Hf-Si bonds with some remnant Si-O bonds. In contrast with the multi-phase feature of crystalline HfSi 2 that has been reported to occur by annealing hafnium metal on ultrathin SiO 2, our STM study reveals the formation of &quot;irregularly shaped&quot; suicides upon silicidation. These suicides contain some oxygen in the form of Si-O bonds, so they exhibit a slightly insulating behavior in the spectroscope mode of STM.<p /><p>Language: en</p>",
language="en",
issn="0374-4884",
doi="",
url="http://dx.doi.org/"
}