Spin-dependent tunneling has been investigated for ferromagnetic tunnel junctions with a new structure, which consists of a hard ferromagnetic insulating granular thin film sandwiched between two soft ferromagnetic layers, or soft ferromagnetic and non-ferromagnetic layers. The granular film, consisting of ferromagnetic Co80Pt20 nanosize particles embedded in a SiO2 matrix with 13 nm thickness, has a high coercive force. The film was prepared by co-sputtering of Co80Pt20 and SiO2 targets on a glass substrate with a Cr or a Co80Pt20/Fe underlayer as a bottom electrode. A ferromagnetic Co9Fe layer as a top electrode was deposited over the granular film to form cross pattern junctions of 0.01 mm2 junction area through a metal mask. The tunneling magnetoresistance up to 4.5% at RT was observed for a Co9Fe/Co80Pt20-SiO2/Co 80Pt20/Fe junction at a low field.
|Journal||Japanese Journal of Applied Physics, Part 2: Letters|
|Issue number||10 SUPPL. B|
|Publication status||Published - 1997 Oct 15|
- Hard magnetic
ASJC Scopus subject areas
- Physics and Astronomy(all)