title: Investigation of magnetic properties and microstructure of ultrathin Co films grown on Si(111)- 7 x 7 surface.
abstract: Magnetic properties and growth mechanism of ultrathin Co films on Si(111)-7 x 7 surface have been studied by using both surface magneto-optic Kerr effect (SMOKE) and scanning tunneling microscopy (STM), respectively. STM results show that the growth mechanism of ultrathin Co films on Si(111)-7 x 7 surface at room temperature belongs to Stranski-Krastanov (SK) growth mode. Due to formation of CoSi2 layer, no magnetic signal could be detected by SMOKE for 1-4 ML Co deposited on Si(111) surface. Because of rougher surface, both longitudinal and perpendicular magnetic anisotropy configuration appear for 4.2-10 ML Co/Si(111) films. When the Co thickness is increased to 10 ML, only longitudinal anisotropy configuration is found, resulting from the contribution to the volume anisotropy. Furthermore, in-plane coercivity increases with Co coverage because of enhancement of ferromagnetic coupling with Co thickness, out-of-plane coercivity increases with Co coverage due to the increment of demagnetized field, induced by the rougher Co surface and pinhole structures.
authors: Department of Physics, Tunghai University, Taichung, 407 Taiwan, ROC.
authors: H W
authors: HW
authors: Chang
authors: J S
authors: JS
authors: Tsay
authors: Y C
authors: YC
authors: Hung
authors: W Y
authors: WY
authors: Chan
authors: W B
authors: WB
authors: Su
authors: C S
authors: CS
authors: Chang
authors: Y D
authors: YD
authors: Yao
mesh_terms: D003035:Cobalt / Q000737:chemistry*; D003460:Crystallization / Q000379:methods*; D008280:Magnetics; D008422:Materials Testing; D008567:Membranes, Artificial; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D012825:Silicon / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D008567:Membranes, Artificial; D003035:Cobalt; D012825:Silicon