MTL Fabrication


The electron-beam lithography (EBL) facility enables writing patterns of arbitrary geometries with minimum features sizes as fine as 5 nm. The facility is based on an Elionix FS-125 electron-beam lithography tool operating at 125 keV with a field emission source and a laser interferometer controlled stage capable of holding wafers op to 200 mm diameter. Other features of the tool include laser height sensing of the sample, with automatic Z stage compensation, minimum beam diameter of 1.8 nm, maximum beam current of 100 nA and Proximity Effect Correction (PEC) with Genisys Beamer software.

Facility Procedures

Electron-Beam-Lithography Facility (EBL)
The Elionix FS-125 operates at 125 keV acceleration with a field emission source capable of 25 pA to 100 nA of beam current. The pattern generator maximum speed is 16 MHz with field sizes of 75, 150, 300 and 600 microns at 125 keV. Pixel step sizes from 0.3nm to 25 nm are available. The stage accommodates wafers from 50 mm up to 200 mm and masks to 150 mm. Up to 9 small pieces may also be mounted at one time.


Please refer to the Machine Charge Chart.

Users of the Elionix will need to have an MTL CORAL account (please note that a CMSE CORAL account does not allow billing on the Elionix). Please go to Become an MTL user if you do not already have a CORAL account.

The Elionix FS-125 is a user-run tool. First time e-beam lithography users should contact Mark K Mondol with a proposed process. After meeting to discuss the process the first training session can be arranged. To become a qualified user of the FS-125 requires 4-6 hours of training, after 2-3 initial training sessions users can book and use the tool on their own. However, to fully use all the functionality the tool offers requires many hours of training and experimentation.

What you need to know

There are many and varied parameters that need to be considered before writing a pattern with e-beam lithography. Here is a short list:

To book time in EBL, please use CORAL.


The MIT Electron-Beam Lithography Facility was made possible in part by generous support from the Gordon and Betty Moore Foundation, the Department of Electrical Engineering & Computer Science, Microsystems Technology Laboratories, Office of the Provost, Office of the Vice President for Research, Research Laboratory of Electronics, School of Engineering, School of Science, and faculty from across the Institute.


Facilities Manager
Mark K. Mondol
Room 38-177
617.253.9617—Office Tel
617.253.3416—Raith Tel