Arrays of nanoscale magnetic dots: Fabrication by x-ray interference lithography and characterization

Journal Article · Mon Nov 22 00:00:00 EST 2004 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.1821649· OSTI ID:20634461

Heyderman, L J; Solak, H H; David, C; Atkinson, D; Cowburn, R P; Nolting, F ^[1]

---

1. Laboratory for Micro- and Nanotechnology, Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland)

X-ray interference lithography (XIL) was employed in combination with electrodeposition to fabricate arrays of nanoscale nickel dots which are uniform over 40 {mu}m and have periods down to 71 nm. Using extreme-ultraviolet light, XIL has the potential to produce magnetic dot arrays over large areas with periods well below 50 nm, and down to a theoretical limit of 6.5 nm for a 13 nm x-ray wavelength. In the nickel dot arrays, we observed the effect of interdot magnetic stray field interactions. Measuring the hysteresis loops using the magneto-optical Kerr effect, a double switching via the vortex state was observed in the nickel dots with diameters down to 44 nm and large dot separations. As the dot separations are reduced to below around 50 nm a single switching, occurring by collective rotation of the magnetic spins, is favored due to interdot magnetic stray field interactions. This results in magnetic flux closure through several dots which could be visualized with micromagnetic simulations. Further evidence of the stray field interactions was seen in photoemission electron microscopy images, where bands of contrast corresponding to chains of coupled dots were observed.

• OSTI ID: 20634461
• Journal Information: Applied Physics Letters, Vol. 85, Issue 21; Other Information: DOI: 10.1063/1.1821649; (c) 2004 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ELECTRODEPOSITION
ELECTRON MICROSCOPY
EXCHANGE INTERACTIONS
EXTREME ULTRAVIOLET RADIATION
FABRICATION
FERROMAGNETIC MATERIALS
HYSTERESIS
IMAGES
INTERFERENCE
KERR EFFECT
MAGNETIC FLUX
MAGNETO-OPTICAL EFFECTS
NICKEL
PHOTOEMISSION
QUANTUM DOTS
SIMULATION
WAVELENGTHS
X RADIATION