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Infrastructure of Thin Films Division in IMP. Hubert Głowiński and Janusz Dubowik, IFM PAN. Outline. VNA-FMR FMR PIMM. Dynamic measurements. VSM PPMS MOKE. Static measurements. GIXRD XRF. Structural characterization. Field sweep FMR.
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Infrastructure of Thin Films Division in IMP Hubert Głowiński and Janusz Dubowik, IFM PAN
Outline VNA-FMR FMR PIMM Dynamic measurements VSM PPMS MOKE Static measurements GIXRD XRF Structural characterization
Field sweep FMR During field sweep FMR experiment magnetization vector changes its direction
FMR • X-band spectrometer 9.18 GHz • Field up to 11 kOe Gaussmeter Lock-in Microwave bridge Field sweep controller
VNA-FMR • Frequency up to 40 GHz On frequency sweep FMR experiment magnetization vector does not change its direction Port 1 Port 2 Próbka Microwave field Coplanar waveguide External magnetic field
CPW – coplanar waveguide External magnetic field Magnetic field lines Magnetic field lines Electric field lines Electric field lines Simulated current Homogenous current I. Neudecker et al. JMMM 307 (2006) 148–156
Channelized Coplanar Waveguide The vias are acting as a microwave wall The other determining factor in the high frequency performance of the vias is the spacing between the rows of the vias. The wider the spacing, the lower the cutoff frequency and the closer the spacing the higher the cutoff frequency. http://mpd.southwestmicrowave.com/pdf/Launch_Report.pdf
VNA-FMR Gaussmeter VNA Helmholtz’s coils Power supply
Au Co Au Co Au Co Au Co Au Co Au Ti Si VNA-FMR Frequency sweep mode Different fields Field sweep mode Different frequencies
Pulsedinductivemicrowavemagnetometer (PIMM) Pulse generator Trigger Port Port Sampling oscilloscope Pulse magnetic field Bandwidth 20 GHz Pulse risetime 55 ps Pulse amplitude 10 V Sample External magnetic field
PIMM Pulse generator Oscilloscope Helmholtz coils Power supply
Vibrating Sample Magnetometer – VSM • Frequency: 35 Hz • Dual pickup coils • Magnetic field: up to 16 kOe • Temperature: -100oC to 250oC Generator Loudspeaker Glass pipe Gaussmeter Hallotron PC Power supply Pickup coils Lock-in M.Matczak, Thesis, Politechnika Poznańska, Poznań, 2011
PHYSICAL PROPERTY MEASUREMENT SYSTEM (PPMS) • Options • VSM • Resistance • Torque magnetometer • PPMS system properties: • Temperature range: 2 K - 350 K. • Magnetic field: up to 9 tesla. • Magnetic field ramp rate: determinedby magnet and power supply. • Temperature and magnetic field may beramped during the measurement.
Z axis Stepper motor Modulator Lens Polarizer Mirror Laser Elektromagnet Modulator Analyzer Gaussmeter Power supply Lens Lock-in PC Detector MOKE Wavelength λ=640 nm M.Matczak, Thesis, Politechnika Poznańska, Poznań, 2011
MOKE – device setup • Laser diode • Polarizer • Modulator • Lens • Electromagnet • Sample holder and table • Mirror • Analyser • Lens • Detector (fotodiode) • Magnetic field sensor M.Matczak, Thesis, Politechnika Poznańska, Poznań, 2011
Au Co Au Co Au Co Au Co Au Co Au Ti Si MOKE
XRF Characteristic radiation • We can measure: • Thickness of thin films (up to 200 nm) • Chemical elements composition Multichannel analyzer 10 keV / 1024 channels 1 – X-ray source, 2 - collimator, 3 – sample holder, 4 - detector K. Załęski, Masters thesis, UAM Wydział Fizyki, Poznań 2007 Wikipedia
detector aperture X-ray source sample GIXRD 2θ varies 0o - 10o Seifert, model XRD 3003, X-ray source Cu-K (wavelength λ=0.15419 nm) Interference of the wave reflected from surface of the film and the surface of the substrateresults in Kiessiga fringes. Allows to measure thickness of thin films P. Kuświk, PhD dissertation, IFM PAN, Poznań, 2010
Summary • We are able to characterize magnetically samples (effective fields, anisotropy, damping parameter) • We are able to characterize structure of the sample (film thickness, sublayer thickness, chemical composition)