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 and their expected distribution - 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. 

Developers:

Mohammad M Kabir, Qing Ding 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. Hemangg Singh Rajput is a Master's student in the department of Mechanical Science and Engineering at the University of Illinois at Urbana-Champaign. Yuhang Yang and Sixian Jia are PhD students in the department of Mechanical Science and Engineering at the University of Illinois at Urbana-Champaign. Their work focuses on characterizing and controlling for process variations within the two-photon lithography process.

Darren Adams is a Senior Research programmer with the National Center for Supercomputing Applications at UIUC. Kimani Toussaint is a Professor of Engineering at Brown University. His research focuses on developing novel optical tools for biomedical imaging and nano-manufacturing. Chenhui Shao is an Assistant Professor in the department of Mechanical Science and Engineering at UIUC. His research aims to enhance the automation and intelligence of manufacturing by applying methodologies such as machine learning, statistics, and automatic control.

Researchers should cite this work as follows:

• Mohammad Mahfuzul Kabir, Darren K Adams, Varun Ajit Kelkar, Kimani C Toussaint (2021), "Two Photon Lithography," https://nanohub.org/resources/tpl. (DOI: 10.21981/BWCA-2B15).

  BibTex | EndNote

1. 3d printing
2. Jupyter notebooks
3. lithography
4. Micro/Nanofabrication
5. nanomanufacturing
6. nanoMFG Node
7. nanophotonics
8. polymerization
9. processing
10. two-photon lithography