Effect of chemical composition on the elastic and electrical properties of the boron-oxygen-yttrium system studied by ab initio and experimental means
2004 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, Vol. 69, no 9Article in journal (Refereed) Published
The effect of chemical composition on the elastic and electrical properties is studied for the BOxYz system with 0.27less than or equal toxless than or equal to1.14 and 0.36less than or equal tozless than or equal to0.08. We use ab initio calculations to obtain the elastic constants and density of states for BO1.5 and the BOY phase (yttrium substituting for oxygen in the boron suboxide structure). For decreasing x values, the elastic modulus is predicted to increase from 11 to 340 GPa, while electronic structure calculations suggest a shift in electrical properties from insulating to metallic. Thin films in the B-O-Y system are grown by reactive rf magnetron sputtering. As x decreases from 1.14 to 0.27, the elastic modulus increases from 12 to 282 GPa, which is a factor of 24, while resistivity decreases from 7.6+/-0.4 to (3.8+/-0.1)x10(-2) Omegam. The observed shifts in elasticity and resistivity are shown to be induced by the associated changes in chemical bonding from van der Waals type in BO1.5 to icosahedral type in the BOY phase.
Place, publisher, year, edition, pages
2004. Vol. 69, no 9
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-46249DOI: 10.1103/PhysRevB.69.092103OAI: oai:DiVA.org:liu-46249DiVA: diva2:267145