Skip to main content
OSTI.GOVU.S. Department of Energy Office of Scientific and Technical Information
U.S. Department of Energy
Office of Scientific and Technical Information
 

Magnetic properties of epitaxial Co-doped anatase TiO2 thin films with excellent structural quality

Journal Article · · Journal of Vacuum Science and Technology B--Microelectronics and Nanometer Structures, 24(4):2012-2017
DOI:https://doi.org/10.1116/1.2216723· OSTI ID:946402
; ; ; ; ; ; ; ; ;
The heteroepitaxy of Co-doped anatase TiO2 on LaAlO3(001) has been refined with the goal of determining the relationship between structural quality and magnetic ordering. By significantly reducing the deposition rate and substrate temperature, well-ordered Co:TiO2 films with unprecedented crystalline quality were obtained by oxygen-plasma-assisted molecular beam epitaxy, as characterized by x-ray diffraction. These films exhibit uniform Co doping, with no evidence of Co segregation or secondary phases throughout the film depth or on the surface. Despite the improvement in crystalline quality and Co distribution, the films exhibit negligible ferromagnetism, with saturation moments of only ~0.1 μB/Co. This loss of ferromagnetism is in stark contrast to faster-grown Co:TiO2 films, where a higher growth rate and substrate temperature typically result in lower crystalline quality, a highly non-uniform Co distribution, and average saturation moments of ~1.2 μB/Co. The presence of ferromagnetism in faster-grown Co:TiO2 does not appear to arise from intrinsic point defects present in the bulk material, such as charge-compensating oxygen vacancies, but is instead attributed to the presence of extended structural defects.
Research Organization:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Organization:
USDOE
DOE Contract Number:
AC05-76RL01830
OSTI ID:
946402
Report Number(s):
PNNL-SA-48059; 16895; KC0203020
Journal Information:
Journal of Vacuum Science and Technology B--Microelectronics and Nanometer Structures, 24(4):2012-2017, Journal Name: Journal of Vacuum Science and Technology B--Microelectronics and Nanometer Structures, 24(4):2012-2017
Country of Publication:
United States
Language:
English

Similar Records

Ferromagnetism and structure of epitaxial Cr-doped anatase TiO2 thin films
Journal Article · Fri Mar 31 23:00:00 EST 2006 · Physical Review. B, Condensed Matter and Materials Physics · OSTI ID:881934
Negligible Magnetism in Excellent Structural Quality Cr[subscript x]Ti[subscript 1-x]O[subscript 2] Anatase: Contrast with High-T[subscript C] Ferromagnetism in Structurally Defective Cr[subscript x]Ti[subscript 1-x]O[subscript 2]
Journal Article · Mon Jul 19 00:00:00 EDT 2010 · Phys. Rev. Lett. · OSTI ID:1008670
Epitaxial Growth and Properties of MBE Grown Ferromagnetic Co-doped TiO₂ Anatase Films on SrTiO₃(001) and LaAlO₃(001)
Journal Article · Tue Oct 15 00:00:00 EDT 2002 · Thin Solid Films, 418(2):197-210 · OSTI ID:15006939

Related Subjects

Environmental Molecular Sciences Laboratory