Novel hard, tough HfAlSiN multilayers, defined by alternating Si bond structure, deposited using modulated high-flux, low-energy ion irradiation of the growing film
2015 (English)In: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 33, no 5, 05E103-1-05E103-9 p.Article in journal (Refereed) Published
Hf1-x-yAlxSiyN (0 less than= x less than= 0.14, 0 less than= y less than= 0.12) single layer and multilayer films are grown on Si(001) at 250 degrees C using ultrahigh vacuum magnetically unbalanced reactive magnetron sputtering from a single Hf0.6Al0.2Si0.2 target in mixed 5%-N-2/Ar atmospheres at a total pressure of 20 mTorr (2.67 Pa). The composition and nanostructure of Hf1-x-yAlxSiyN films are controlled by varying the energy Ei of the ions incident at the film growth surface while maintaining the ion-to-metal flux ratio constant at eight. Switching E-i between 10 and 40 eV allows the growth of Hf0.78Al0.10Si0.12N/Hf0.78Al0.14Si0.08N multilayers with similar layer compositions, but in which the Si bonding state changes from predominantly Si-Si/Si-Hf for films grown with E-i = 10 eV, to primarily Si-N with E-i = 40 eV. Multilayer hardness values, which vary inversely with bilayer period Lambda, range from 20 GPa with Lambda = 20 nm to 27 GPa with Lambda = 2 nm, while fracture toughness increases directly with Lambda. Multilayers with Lambda = 10nm combine relatively high hardness, H similar to 24GPa, with good fracture toughness. (C) 2015 American Vacuum Society.
Place, publisher, year, edition, pages
A V S AMER INST PHYSICS , 2015. Vol. 33, no 5, 05E103-1-05E103-9 p.
Condensed Matter Physics
IdentifiersURN: urn:nbn:se:liu:diva-121905DOI: 10.1116/1.4920980ISI: 000361229000003OAI: oai:DiVA.org:liu-121905DiVA: diva2:860742
Funding Agencies|U.S. Department of Energy [DE-FG02-07ER46453, DE-FG02-07ER46471]; Swedish Foundation for Strategic Research project Designed Multicomponent Coatings, MultiFil; U.S. Department of Defense Science, Mathematics, and Research for Transformation program; Swedish Government Strategic Research Area Grant (SFO MAT-LiU) on Advanced Functional Materials; Swedish Research Council (VR) [2009-00971]2015-10-132015-10-122016-08-31