Domain observation with Polarized Secondary Electrons

A new method for observing domain and other microstructure features of films by detecting secondary electron spins is described. The sample surface was scanned using an electron gun, and one component of the polarization vectors of the secondary electrons emitted, which reflect the magnetization, were detected. The detected signals were converted into video signals to obtain images of magnetic domains. As opposed to previous methods, this technique features 1) reflectivetype resolution down to 20-30 nm, 2) the possibility for three simultaneous polarization vector component measurements, and 3) magnetic domain images which are independent of the surface topographic contrast.