Premium
Hot‐Wire Assisted ALD: A Study Powered by In Situ Spectroscopic Ellipsometry
Author(s) -
Kovalgin Alexey Y.,
Yang Mengdi,
Banerjee Sourish,
Apaydin Ramazan O.,
Aarnink Antonius A. I.,
Kinge Sachin,
Wolters Rob A. M.
Publication year - 2017
Publication title -
advanced materials interfaces
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.671
H-Index - 65
ISSN - 2196-7350
DOI - 10.1002/admi.201700058
Subject(s) - materials science , atomic layer deposition , tungsten , wafer , etching (microfabrication) , ellipsometry , substrate (aquarium) , silicon , deposition (geology) , chemical engineering , analytical chemistry (journal) , thin film , nanotechnology , layer (electronics) , optoelectronics , metallurgy , organic chemistry , chemistry , paleontology , oceanography , sediment , geology , engineering , biology
Hot‐wire assisted atomic layer deposition (HWALD) is a novel energy‐enhancement technique. HWALD enables formation of reactive species (radicals) at low substrate temperatures, without the generation of energetic ions and UV photons as by plasma. This approach employs a hot wire (tungsten filament) that is heated up to a temperature in the range of 1300–2000 °C to dissociate precursor molecules. HWALD has the potential to overcome certain limitations of plasma‐assisted processes. This work investigates the ability of a heated tungsten filament to catalytically crack molecular hydrogen or ammonia into atomic hydrogen and nitrogen‐containing radicals. The generation of these radicals and their successful delivery to the wafer (substrate) surface are experimentally confirmed by dedicated tellurium‐etching and silicon‐nitridation experiments. It further reports on deposition of low‐resistivity oxygen‐free tungsten films by using HWALD, as well as on the effect of hot‐wire‐generated nitrogen radicals and atomic hydrogen in deposition of aluminum nitride and boron nitride films. In parallel, this work provides important illustrative examples of using in situ real‐time monitoring of deposition and etching processes, together with extracting a variety of film properties, by spectroscopic ellipsometry technique.