Fabrication of buried channel waveguides in fused silica using focused MeV proton beam irradiation
A Roberts, ML vonBibra
JOURNAL OF LIGHTWAVE TECHNOLOGY | IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC | Published : 1996
Low-loss channel waveguides have been fabricated in fused silica using a beam of MeV protons focused down to a spot size of several microns. By using a combination of beam and sample scanning, single- and multimode graded index waveguides with lateral dimensions down to approximately 5 μm x 5 μm have been fabricated using ion doses in the range (3 × 1014)-(6 × 1016) ions/cm2. Typical beam currents in the range 100 pA-10 nA were used. Optical mode profiles have been measured at 670 nm and propagation losses of the order of 3 dB/cm measured in unannealed samples. Annealing the substrate for one h at 500°C reduced these losses to below 0.5 dB/cm.