Self Diffraction Holographic Techniques For Investigation Of Photosensitive Materials

Holographic techniques are powerful tools to study photosensitive materials due to the high sensitivity of diffraction measurement and the ability to detect dynamic gratings. The self diffraction technique consists in to project an interference fringe pattern into the photosensitive material and to measure, in real time, the self-diffraction of the interfering beams, at the grating generated in the photosensitive material. Besides the higher sensitivity, such measurement allows to measure simultaneously and separately the phase and the amplitude grating contributions, as well as thin or thick gratings. In order to demonstrate potentiality of this technique we measured the kinetic constant of the photo-reaction in positive photoresists (AZ types) and negative SU-8 photoresist, as well as the maximum values of the refractive index and of the absorption coefficient modulations induced in these materials at different wavelengths of exposure. The same measurements were performed in SB based chalcogenide glasses in order to evaluate the potential of such materials to be used as optical data storage devices. © 2013 SPIE.8776The Society of Photo-Optical Instrumentation Engineers (SPIE)Megla, G.K., Optical properties and applications of photochromic glass (1966) Appl. Opt., 5, pp. 945-960Reichmanis, E., Houlihan, F.M., Nalamasu, O., Neenan, T.X., Chemical amplification mechanisms for microlithography (1991) Chem. Mater., 3, pp. 394-407Kolobov, A.V., Tominaga, J., Chalcogenide glasses as prospective materials for optical memories and optical data storage (2003) J. Mat. Sci. Mat. Elec., 14, pp. 677-680Cheben, P., Calvo, M.L., A photopolymerizable glass with diffraction efficiency near 100% for holographic storage (2001) Appl. Phys. Lett., 78, pp. 1490-1492Cordeiro, C.M.B., Freschi, A.A., Cescato, L., Progress on holographic techniques to measure real-time phase and amplitude gratings in photosensitive materials (2003) J. Opt. A: Pure Appl. Opt., 5, pp. 170-174Pinsl, J., Gehrtz, M., Bräuchle, C., Phase-modulated holography: A new technique for investigation of solid state photochemistry and hologram formation mechanisms (1986) J. Phys. Chem., 90, pp. 6754-6756MacK, C.A., Absorption and exposure in positive photoresist (1988) Applied Optics, 27, p. 4913Dill, F.H., Characterization of positive photoresists (1975) IEEE Trans. Electron Dev, 22, p. 445Teh, W.H., Durig, U., Drechler, U., Guntherodt, C.G., Effect of low numerical-aperture femtosecond twophoton absorption on (SU-8) resist for ultrahigh-aspect-ratio microstereolithography (2005) J. Appl. Phys., 97, pp. 054907-0549011Zakery, A., Elliott, S.R., Optical properties and applications of chalcogenide glasses: A review (2003) J. Non-Cryst. Sol., 330, pp. 1-12Sati, D.C., Kumar, R., Mehra, R.M., Jain, H., Ganjoo, A., Kinetics of photodarkening in a-As2Se3 thin films (2009) J. Appl. Physics, 105, p. 123105Avila, L.F., Freschi, A.A., Cescato, L., Holographic technique for measurement of the kinetic constant and optical modulations of photosensitive materials (2010) Appl. Optics, 49, p. 349