Scanning Electron Microscope/E-beam writer TESCAN MIRA3


Vojtěch Švarc

A scanning electron microscope (SEM) is a type of microscope where a focused beam of electrons is scanned over the sample to generate its image or to modify the sample surface with nanometre resolution (usually better than 10 nm). The sample image is most often formed by detecting secondary and backscattered electrons emitted from the impact location of the beam.

The preferential usage of SEM in the Nanofabrication laboratory is for e-beam lithography (EBL), where the resist-coated sample is selectively exposed to the focused electron beam by means of an electrostatic beam blanker and the sophisticated nanolithography attachment, allowing the preparation of very small patterns (<50 nm) on the resist surface. The stage accuracy of a common SEM is the key limitation for most lithography patterning. Therefore, the instrument is equipped with the laser interferometer stage (LIS) to allow for ultra-high resolution structuring of areas of a millimeter in size.

Mira3 XMH

A Scanning Electron Microscope combined with a precise laser-based interferometric stage for e-beam patterning of areas up to 45 mm x 45 mm.

Features

  • Scanning Electron Microscope with Schottky cathode for high-resolution/hig­hcurrent/low-noise imaging
  • Laser-based interferometric closed-loop XYZ stage with nanometric resolution and accuracy and repeatability in the other of tens of nanometers
Lithography system Raith Elphy Plus
Proximity effect correction software
Active anti-vibration suspension system
Sample sizeup to 2" wafer size
Chamber vacuum< 9e-3 Pa (< 5e-4 Pa reachable)

Scanning Electron Microscope (SEM)

Tescan Mira 3FEG
Accelerating voltage200 V – 30 kV
Probe current2 pA – 200 nA
View field> 6 mm x 6 mm at WD 9 mm
Magnification1× – 1 000 000×
Detectors (resolution)Secondary Electron (SE) detector (1.2 nm at 30 kV)
In-Beam SE detector (1.0 nm at 30 kV)


Laser Interferometry Stage (LIS) Closed loop

Patterning area45 mm x 45 mm (x 25 mm)
Resolution2 nm
Stitching accuracy<= 100 nm
Overlay accuracy<= 100 nm
Raith Elphy Plus

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