Silicon waveguide sidewall smoothing by KrF excimer laser reformation
Journal
Journal of Lightwave Technology
Journal Volume
27
Journal Issue
7
Pages
887-892
Date Issued
2009
Author(s)
Abstract
A novel laser-reformation technique is presented for sidewall smoothing of silicon waveguides. A KrF excimer laser is used to melt and reform the sidewalls to reduce the surface roughness. Atomic-force-microscopy measurement shows that the root-mean-square (rms) roughness is reduced from 14 to 0.24 nm. The calculated scattering loss is reduced to 0.033 dB/cm. The waveguide profile after laser illumination at an incident angle of 75deg transforms to a shape of arch. The crystal quality of laser-illuminated silicon wafer characterized by microwave reflection photoconductance-decay carrier lifetimes shows 94% less damage than the furnace-treated wafer.
Type
journal article