Date of Submission
Academic Programs and Concentrations
Project Advisor 1
Christopher N. LaFratta
Two photon polymerization (TPP) is an additive manufacturing technology that creates nano- and micro- scale structures with arbitrary 3-D geometry. As TPP enables people to make three dimensional structures smaller than the diffraction limit, it has been used in optics and bioengineering, and has great potential to contribute to lab-on-a-chip applications. However there has been a lack of standard ways to characterize structures made by TPP. Most methods of a line’s height for example, involve the measurement of structures half submerged into to the surface, which could be misleading as it does not reveal the full profile. In order to ensure the integrity and improve the design, this project propose several model structures to measure spatial resolution, shrinkage, and roughness through the idea of radical diffusion within the resin of TPP and the solvent surface tension. As the structures of interest are created suspended in the resin with little contact to the surface and will fall due to surface tension, a ~1.2 μm tall and ~200 nm wide line was realized. Additionally, with the proposed model, an increase of shrinkage and surface roughness due to an increase of z-step were observed by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM).
Open Access Agreement
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.
Guo, Xiaofei, "The Metrology of Two Photon Polymerization" (2019). Senior Projects Spring 2019. 63.