Improved photosensitive polymeric materials for 3-D WORM optical data storage using two-photon fluorescent writing and readout

ORGN 446

Kevin D. Belfield, belfield@mail.ucf.edu, Ciceron O. Yanez, cyanez@mail.ucf.edu, Sheng Yao, syao@mail.ucf.edu, Zhen-Li Huang, huangz@creol.ucf.edu, and Claudia C. Corredor, ccorredo@mail.ucf.edu. Department of Chemistry and CREOL, College of Optics and Photonics, University of Central Florida, 4000 Central Florida Blvd., P.O. Box 162366, Orlando, FL 32816-2366
We report a photosensitive polymeric (write many read once) WORM system designed to improve the size features and two-photon cross section of the photoacid generator (PAG). The PAG, 9,9-diethyl-(bis-(styryltriphenyl sulfonium hexafluoro phosphonate))fluorene (1), was made by means of a four step synthesis starting from flourene. A VBC-co-PMMA phosphorylated copolymer was employed as a matrix for thin films (single-layer, one-photon) recording, and two different photoinduced crosslinked thiolene polymers were used for making the thicker film matrices (two-photon writing and readout). One-photon writing was achieved by the monoprotonation of the fluorene dyes when exposed to high intensity broadband UV light in presence of PAG (1). Two-photon writing was performed by inducing the photolysis of (1) upon high intensity femtosecond 760 nm laser irradiation to subsequently monoprotonate the dyes within the polymeric film. The changes in florescence emission of the exposed photosensitive systems were used for one and two-photon readout.