Ultra-Low Shrinkage Hybrid Photosensitive Material for Two-Photon Polymerization Microfabrication

TLDR

The study investigates two‑photon polymerization of a non‑shrinking, photosensitive zirconium sol‑gel material. The hybrid material, containing up to 30 mol % ZPO, can be photostructured and its refractive index tuned by adjusting inorganic content. Adding ZPO boosts photosensitivity, enabling high‑resolution 3D photonic crystals with a near‑IR band‑stop that require no shrinkage compensation, and the material’s tunable optical, mechanical, and chemical properties make it versatile for two‑photon polymerization.

Abstract

Investigations into the structuring by two-photon polymerization of a nonshrinking, photosensitive, zirconium sol−gel material are presented. This hybrid material can be photostructured even when it contains up to 30 mol % of zirconium propoxide (ZPO); by varying the material's inorganic content, it is possible to modify and tune its refractive index. The introduction of ZPO significantly increases the photosensitivity of the resulting photopolymer. The fabricated three-dimensional photonic crystal structures demonstrate high resolution and a clear band-stop in the near-IR region. In contrast to common practice, no additional effort is required to precompensate for shrinkage or to improve the structural stability of the fabricated photonic crystals; this, combined with the possibility of tuning this material's optical, mechanical, and chemical properties, makes it suitable for a variety of applications by two-photon polymerization manufacturing.