Product Code: ICAL09_P119

Femtosecond Laser Written Microstructures in PMMA and PDMS at 800nm for Photonic Applications
Authors:
Deepak K.L.N., University of Hyderabad; Hyderabad India
R.S.S. Kumar, School of Physics, University of Hyderabad; Hyderabad India
Narayana Rao Desai, University of Hyderabad; Hyderabad India
Venugopal Rao Soma, University of Hyderabad; Hyderabad India
Presented at ICALEO 2009

Microstructures, including gratings and photonic crystal structures, have been fabricated in bulk PDMS and PMMA using femtosecond pulses. The variation of structure width with different writing conditions (focusing, speed, energy) has been investigated. Physical characterization of the structures was performed using laser confocal and SEM techniques. Structural modifications at the focal volume have been investigated using micro-Raman, UV-Visible, and FT-IR techniques. Diffraction efficiencies of the gratings were calculated followed by the refractive index change in PDMS and PMMA. Highest diffraction efficiencies of 34% and 10%, for the first order, were observed in PMMA and PDMS respectively. Refractive index change of 10-3 and higher could be achieved. Fabrication of microchannels on the surface and within the bulk was also attempted. We present our results on the fabrication and characterization of these microstructures and microchannels. Several applications resulting from these structures will also be discussed.