Facilities of USDL

Laser Scanning Magnetic Microscope (LSMM)

Specification

  • Beam size - minimum 1μm
  • Minimum scanning step - 100nm
  • Laser wavelength - 660nm
  • Laser maximum power - 110mW
  • Maximum out-of-plane field - About 1kOe
  • Maximum in-plane field - About 1kOe
  • Sample heating using Ceramic heater
  • No rotator, Current injection and Voltage measurement is possible.

Magnetoresistance & Ferromagnetic Resonance Measurement System (a.k.a. RX78-2)

Specification

  • ~1T Magnetic field
  • ~100mA DC & AC current
  • ~10μV resolution Voltmeter
  • ~0.1˚ resolved rotation
  • ~100nV resolution Lock-in amplifier
  • 9kHz ~ 40GHz, -20 ~ +10dBm Signal generator
  • 9kHz ~ 26.5GHz, -120 ~ -20dBm Spectrum analyzer

Wide-field Kerr Microscope (a.k.a. 미경이)

About Kerr microscope

  • People usually depict each pole of magnet as blue and red. However, In reality magnetism is hardly visible. One way to observe magnetism optically is using magneto-optical kerr effect(MOKE), which is change of polarization after refection on magnetic surface. This wide-field polarized microscope is capable of coloring magnetization direction of magnetic film, either perpendicular or planar with either bright or dark field mode, applying external magnetic field.
  • Current spatial resolution is ~0.5μm, working on improving it. (both systemically and optically)

Low Temperature Probe Station

Specification

  • DC voltage noise : ~3uV
  • Out of plane field ~ 4000 Oe
  • Temperature range : 100K ~ 400K
  • Vacuum level : 1 torr

Feature

  • Applying temperature gradient
  • RF probe

THz TDS (Terahertz Time-Domain Spectroscopy)

THz-TDS can

  • Measure THz range complex material parameters of sample: refractive index and conductivity. Also it can investigate THz Dynamics(spin wave) and other ps order effects.

Specification

  • 8 K ~ 350 K
  • In-plane vector magnet (max. 300 mT)
  • THz spectroscopy range: 0.2THz ~ 4THz
  • Time resolution 0.33ps
  • Max Frequency resolution 1.2GHz
  • THz pulse peak amplitude below 100V/cm(0.33 Oe)

Magnetic Force Microscope (MFM)

Specification

  • Acoustic enclosure with active vibration isolation table
  • Scan size – maximum 50 μm
  • Sample size – maximum 50 mm
  • manual XY stage (travel range 13 mm)
  • In-plane magnetic field – up to 500 Oe
  • Temperature control – up to 180℃
  • Direct on-axis optical microscope

3D-Magnetic Field MOKE Microscopy RF Probe Station

Specification

  • Perpendicular magnetic field ~0.4 T
  • 360˚ rotatable in-plane magnetic field ~0.35 T
  • MOKE microscope resolution ~0.25 μm
  • Single & GSG tips simultaneous use up to 5
  • Oscilloscope ~3 GHz
  • Pulse generator 100 ps ~ ms
  • Sourcemeter DC & AC current ~100 mA
  • Voltmeter resolution ~10 μV
  • Vector Network Analyzer (latest Keysight model) ~26.5 GHz

Feature

  • DC & RF measurements with 3D magnetic field while imaging magnetizations
  • Domain wall motion, Skyrmion motion, FMR, Spin wave transmission
  • Quick and multi-functional measurements of spin dynamics

Electrical Measurement System with 2T Magnet

Specification

  • ~2T Magnetic field
  • ~100mA DC & AC current
  • ~10μV resolution Voltmeter x2
  • ~0.1˚ resolved rotation
  • ~100nV resolution Lock-in amplifier

Argon Ion Milling & Sputtering System

Specification

  • Base pressure < 8×10-7 Torr
  • Milling uniformity < ±5%
  • Deposition uniformity < ±5%
  • Gridded ion source
  • RF(0.6kW), DC(1kW) Power
  • 2 Sputtering Gun
  • Ultra-High Vacuum Sputtering Chamber

    Specification

    • Total 4 chambers: Main chamber, 2nd chamber, Reactive sputtering chamber, Load-Lock chamber
    • 7 sputtering sources in main chamber, 3 sputtering sources in 2nd chamber, 1 sputtering source in reactive sputtering chamber
    • Base pressure: 9.5 X 10-9 Torr (Main chamber), 3.5 X 10-7 Torr (2nd chamber), ~10-7 Torr (Reactive sputtering chamber)
    • In-situ annealing temperature up to 800℃