Tutorial on Two Photon Lithography Tool

By Mohammad Mahfuzul Kabir1, Varun Ajit Kelkar1

1. University of Illinois at Urbana Champaign

Published on


Two-photon lithography (TPL) is a nano-scale 3-d fabrication technique. TPL depends upon the two-photon polymerization process, whereby two incident photons of light are absorbed by a precursor material leading to polymerization. The smallest feature size (voxel) achievable in a TPL process is typically observed in the form of an ellipsoid and depends upon the incident laser beam parameters and the properties of the precursor material. A ultrafast, femtosecond pulsed laser beam is used as the optical source of polymerization.

This tool calculates the expected voxel dimensions - axial length and cross-sectional diameter - under given experimental conditions provided by the user.

In this tool, the user provides the following two different types of input parameters:

- Optical input parameters: These parameters include the beam power, pulsewidth, repetition rate, exposure time, objective lens numerical aperture (NA) and wavelength. 

- Material input parameters: These input factors are related to the precursor materials and include two-photon polymerization cross-section, two-photon polymerization threshold and concentration of initiator. 


Mohammad M Kabir  and Varun Kelkar are PhD students in the department of Electrical and Computer Engineering at University of Illinois at Urbana Champaign. Their work focuses on developing novel optical instrumentation for two-photon lithography and microscopy techniques.

Cite this work

Researchers should cite this work as follows:

  • Mohammad Mahfuzul Kabir, Varun Ajit Kelkar (2018), "Tutorial on Two Photon Lithography Tool," http://nanohub.org/resources/29211.

    BibTex | EndNote