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Photo of Microscopy/Surface Analysis

Scanning Tunneling Microscopes

Contact: Dr. Raluca Gearba
Location: EER 0.746

Equipment Type:

Microscopy/Surface Analysis

Scanning Tunneling Microscopes (STM)

Surface Analysis

Information the Equipment Can Provide

TMI manages two Scanning Tunneling Microscopes.

  • The Omicron Nanotechnology Low Temperature STM
  • The ambient ATM 300 STM from RHK

The Omicron Nanotechnology Low-Temperature Scanning Probe Microscopy (LT-SPM) system is a dedicated surface science instrument with unique capabilities which include high resolution Low Temperature UHV STM and Non-contact AFM (nc-AFM) technology as well as Kelvin Probe Force Microscopy (KPFM) using Qplus sensors. The system is also optimized for modulation spectroscopy (STS, CITS, etc) by using an external dedicated preamplifier technology.

System Characteristics:

  • With vibration isolation stability in the picometer range, the LT- STM is capable of atomic resolution on metals such as Au(111), while the nc-AFM offers atomic resolution on NaCl, KBr as well as molecules.
  • LHe bath cryostat and LN2 shielding which ensures temperatures of T<5K. The sample reception stage is equipped with a heating system for sample temperature variation up to 55K above LN2.
  • Scan size: 10 x 10 x 1 µm at 300K and reduced by a factor of 2.4 and 5.5 at LN2 and LHe temperatures respectively
  • The system has three vacuum chambers:
    • The INTRO chamber equipped with 4 K-cells for deposition of organic molecules and NaCl
    • The PREP chamber includes a fully rotatable sample manipulator with temperature control from LN2 up to 900°. The manipulator configuration and sample holders designs allows for both direct current heating of samples as well as resistive heating. The chamber is also equipped with a sputtering system (0.1 to 30keV at 55 mm working distance) as well as an Electron Beam Evaporator for extremely clean sub-monolayer and multilayer thin film growth.
    • The LT chamber which hosts the SPM system also includes two carousels for sample storage (up to 18samples and STM/Qplus tips can be stored), a tip preparation tool and an integrated optical fiber for sample illumination as well as lenses holders aligned at 90 and 270 degrees with respect to the sample transfer axis.
  • The MATRIX data acquisition program allows for data collection on multiple channels. STM/nc-AFM and KPFM data can be recorded simultaneously.

The ATM 300 STM is capable of atomic resolution on Au(111) in air.

System Characteristics:

  • Scanning Tunneling Spectroscopy capabilities
  • 5 Angstroms resolution in (x,y) and 0.05 Angstroms resolution in z
  • Tunneling current <1pA
  • Bias voltage: ±1V or ±10V with 10 turn potentiometer resolution
  • Sample size: 16mm dia (image area: 6mm dia)

Fees and Policies

  • UT Users: $7/hour
  • Higher Education/State Agencies: $23hour
  • Corporate/External Users: $24/hour

To become a new user of this facility, please read the Instrument Reservation Information page. If you are already a user you can make a reservation in FBS.

To become a user of this instrument contact the facility manager to schedule a training session. Due to the complexity of the instrument the first stage of training will only involve data collection. Sample and tip transfer will be performed by TMI staff.