Benchmarking UHV STM and AFM Technology

At a Glance

  • 25 K – 1500 K
  • True pA STM
  • Improved dI/dV Spectroscopy
  • Beam Deflection AFM
  • ‘QPlus® sensor’  AFM
  • In-situ Evaporation

The Omicron VT SPM is a well established microscope in many research labs for Scanning Probe Microscopy. It won the prominent R&D award in 1996. To date, more than 500 instruments have been delivered and successfully installed around the world. The volume of research results and publications is a conclusive proof for the performance, quality, and versatility of the Variable Temperature SPM design.


State-of-the-Art STM Technology

The Variable Temperature SPM uses the latest preamplifier technology for true sub-pA scanning tunnelling microscopy and spectroscopy. Stable low current operation is important for the investigation of surfaces that are sensitive or have a low conductivity. For modulation spectroscopy an electronic compensation reduces the influence of parasitic currents. This saves acquisition time and improves results.


Superior AFM Technology

The AFM Technology of the Variable Temperature SPM is based on more than 20 years of experience in Atomic Force Microscopy in UHV. It has been continuously developed and improved. The classic Beam Deflection AFM for contact and non-contact AFM offers the flexibility for many operational modes and different cantilever types. For example high resolution AFM, Friction Force Microscopy, Electrostatic Force Microscopy (EFM), Scanning Kelvin Probe Microscopy (SKPM) and Magnetic Force Microscopy (MFM) are available.

The latest major development is a new AFM preamplifier which increases the detection bandwidth from 450 kHz to 2 MHz. In combination with the new AFM electronics (PLL) of the MATRIX Control System, users can now use high resonant frequency cantilevers for high speed non-contact AFM measurements.

This new preamplifier technology in combination with an improved light source is also available as an upgrade package for existing Variable Temperature AFM’s. Please contact your local sales representative or our service support team (service@omicron.de) if you are interested in upgrading your system.

The new “QPlus®” sensor, based on a tuning fork design, is today extending the possible application range of the Variable Temperature SPM.


Easy and Safe Sensor Exchange

In-situ tip exchange is crucial for multifunctional UHV scanning probe microscopy. Up to 12 different sensors can be stored in the VT chamber. The different sensors are exchanged by remote-control using Omicron’s patented piezo-inertia coarse positioning drives. A sensor is transferred through the UHV system on a transfer plate with a ‘keyhole‘ cut-out. It is picked up by the scanner under user-driven remote-control, minimizing the risk of mechanical damage.


Eddy Current Damping

Introduced as part of the first commercial UHV STM in the 1980’s, the OMICRON eddy current vibration isolation system defined a milestone in UHV SPM technology. The proven design allows high resolution Scanning Tunnelling Microscopy operation even in non-ideal conditions for more than 25 years.