Electron Beam Lithography

The e-beam lithography system (left) is a LEO 1530 field emission scanning electron microscope (FE-SEM) fitted with a laser interferometer controlled stage (right).
• The system accepts wafers or pieces up to 100mm diameter.
• Interferometric measurements are used by the stage calibration route to optimize the placement, size and rotation of the writing field.
• The lithography process is controlled the NPGS system at speeds up to 5 MHz.
• Patterns are prepared as a DesignCad drawing and directly written onto electron beam resist coated samples.
• Writing current, determined by the choice of aperture, ranges from 10pA to 2.5nA.

The system is also available for user-operated SEM imaging. The microscope’s intuitive software interface allows new users to achieve excellent results with minimal training.

We currently stock several varieties of PMMA, ZEP520A and MaN2403 resists.

Electron Beam Lithography can be provided as a service.
Please contact
Todd Simpson for details.

The micrograph (above) shows a square array of 300nm holes on 700nm pitch written in PMMA on silicon. Sub-100nm features are achievable with this system. Also shown is an array of chrome dots on silicon patterned by e-beam lithography and lift-off (right).
Metal lift-off can also be performed with a negative resist to form an array of apertures. The micrographs above show a sample after partial removal of the resist pillars (left) and after complete removal of the resist (right).