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XMCD (x-ray Magnetic Circular Dichroism) is a unique tool to investigate the magnetic phenomena of ferromagnetic materials from the microscopic point of view. It has several capabilities, which are not available by another magnetics techniques. First of all it can give us magnetic information with elemental and chemical specificity. The foremost advantage is the capability of the quantitative separation of spin and orbital moment. And it is surface-sensitive because XMCD is usually based on the total electron yield (TEY) measurement. Sometimes it is disadvantageous when we are interested in the bulk property. But if we can control the surface sensitivity, XMCD will be more useful to investigate the surface or interface region of magnetic thin film and multilayer. CFS and CIS measurement is very old technique to measure x-ray absorption with kinetic energy selectivity. And it is well known that the penetration depth of electron is highly depends on the electron ki-netic energy. It means that we can change the surface sensitivity by selecting the kinetic energy of photo-emitted electrons. In order to measure XMCD in CFS and CIS modes, I modified the data acquisition system of a commercial electron analyser and developed a pulse-magnet to apply a magnetic field to samples. The first measurement was done on the sample of CoFe alloy film with 1 nm thick Al oxide capping layer, which is a part of TMR (Tunnelling Magneto-Resistance) device. The CFS(CIS)-XMCD spectra of Co and Fe L edges were successfully measured and compared with the TEY-XMCD. The kinetic energy was selected to be around 100 eV, in order to maximize the surface sensitivity. When compared with TEY-XMCD spectra, which are measured simultaneously, CFS(CIS)-XMCD shows that the orbital moment contribution to the total magnetic moment is different and there is a clear difference in the dichroism of Auger process between Co and Fe. The detailed analysis of the spectra will be shown in the presentation. Because the CFS(CIS)-XMCD spectra reflects the magnetic properties of the interfacial region between CoFe alloy and Al-oxide layers more efficiently, this measurement will contribute to enhance the understanding the role of the interface in magnetoresistance phenomena. |