High-resolution spin-polarized scanning electron microscopy (spin SEM)
Open Access
- 19 October 2009
- journal article
- Published by Oxford University Press (OUP) in Journal of Electron Microscopy
- Vol. 59 (1), 43-52
- https://doi.org/10.1093/jmicro/dfp047
Abstract
We have developed spin-polarized scanning electron microscopy (spin SEM) with a 5-nm resolution. The secondary electron optics is very important, as it needs to transfer a sufficient number of secondary electrons to the spin polarimeter, due to the low efficiency of the polarimeter. The optics was designed using a three-dimensional (3D) simulation program of the secondary electron trajectories, and it achieves highly efficient collection and transport of the secondary electrons even though the distance between the sample and the objective lens exit of the electron gun remains short. Moreover, the designed optics enables us to obtain clear SEM images in the spin SEM measurement and to precisely adjust the probe beam shape. These functions lead to images with high spatial resolution and sufficient signal-to-noise (S/N) ratios. This optics has been installed in an ultra-high vacuum (UHV) spin SEM chamber with a Schottky-type electron gun for the probe electron beam. We observed recorded bits on a perpendicular magnetic recording medium and visualized small irregularities in the bit shapes around the track edges and bit boundaries. The high resolution of 5 nm was demonstrated by observing the smallest domain composed by a single grain in the recording medium.Keywords
This publication has 20 references indexed in Scilit:
- Direct Imaging of Temperature-Dependent Layered Antiferromagnetism of a Magnetic OxidePhysical Review Letters, 2004
- Magnetic domain structure of a La0.7Sr0.3MnO3 (001) surface observed by a spin-polarized scanning electron microscopeApplied Physics Letters, 2004
- High resolution magnetic force microscopy using focused ion beam modified tipsApplied Physics Letters, 2002
- Magnetic depth profiling Co/Cu multilayers to investigate magnetoresistance (invited)Journal of Applied Physics, 2000
- High spatial-resolution domain-observation of longitudinal thin film media by spin-polarized scanning electron microscopyIEEE Transactions on Magnetics, 1994
- Ultrathin films: magnetism on the microscopic scaleJournal of Magnetism and Magnetic Materials, 1994
- Fine structure in electron channelling patternsJournal of Microscopy, 1985
- The investigation of magnetic domain structures in thin foils by electron microscopyJournal of Physics D: Applied Physics, 1984
- Scanning Electron Microscope Observation of Magnetic Domains Using Spin-Polarized Secondary ElectronsJapanese Journal of Applied Physics, 1984
- Electron spin polarization of secondary electrons ejected from magnetized europium oxidePhysics Letters A, 1976