Unique capabilities of the ReactorSTM system

This instrument is comprised of a state-of-the-art scanning probe microscopy integrated in a tiny flow reactor. As can be seen from the scetch, only the tip, tipholder and the sample are exposed to the reactive gases. The reactor is made of an inert material, such that it is ensured that all detected gas products are coming from chemical reactions on the surface or on the tip. As tip material, Au wire can be used.

When the reactor is closed, a special seal is sealing off the sample against the reactor. This seal can be manipulated and replaced inside the UHV (many seals can be stored in the special seal-storage). Opening and closing of the reactor is performed via a very robust drive mechanism that does not rely on mechanical feedthroughs.

The sample holder is equiped with a heater-filament. In order to achieve higher temperatures, electrons that are emitted from this filament can be accellerated towards the sample on applying a high voltage to either the tip or the sample. In mode of operation with sealed reactor, the temperature of the sample is limited by the max. temperature for the seal: 570K. In UHV mode (seal not in contact with sample), the maximum temperature is > 1000K (depending also on the duration of the high-T treatment).


Schematics of the Flow-Reactor

Annealing a sample in the sample holder




System Specifications

STM scan range (x,y):

2.5 μm

STM scan range (z):

1 μm

max. scan speed:

1-2 image/sec (depending on range, controller, etc.)

sample temperature:

300 K -570 K (during STM operation)

Sample temperature:

300 K - > 1000 K (with open reactor or at preparation stage)

STM resolution:

typical: atoms on Au(111), spec: atoms on HOPG

Reactor volume:

0.5 ml

max. reactor pressure:

> 5 bar

respons time on gas inlet:

3 sec. typ.

Damping system:

air legs + eddy current damping

Sample temperature (UHV):

300K - > 1000 K

Download product brochure:


System layout

The ReactorSTM is availabe as a single instrument on a CF flange, but is also offered as a complete surface science platform for catalysis related research (e.g. including sample manipulation, surface preparation tools and additional analysis instruments, such as LEED, XPS, Auger, etc). Below we show a view of a full-blown high pressure surface science system.

In order to operate the Flow-Reactor, a gas handling manifold is required. We have developed a dedicated gas handling system with the following characteristics. Don't hesitate to contact us for more information:

Characteristics gas handling system

number of gasses:

4 different gasses for mixing, 1 gas for purging

mixing ratio:

1:1 to 1:100

flow regulation:

0 - 10 ml/min at 1 bar

minimal volume:

'no' dead volume

puls mode:


mass spec:

via system or via special line


manual or LabView


Based on the STM system, and AFM version is being developed, which is planned to be an add-on which can be retrofitted later to existing ReactorSTMTM setups.

 CO 0xidation on the Pt(11) surface:

Download product brochure:



Stable imaging on a dirty Au(111) sample during temperature ramp from 130C to 177C, while increasing the pressure from 4mbar to 200mbar (gas: N2)


Previous page: ReactorSPM
Next page: VT-STM