Unique Femtosecond Micromachining Methods in Semi-Insulating and Conducting Silicon Carbide (Preprint)
Abstract
Femtosecond laser pulses were used to write volume phase gratings in bulk 6H semi-insulating and conducting Silicon Carbide (SiC); a wide bandgap semiconductor material provided by Wright-Patterson AFB AFRL/MLPS. Gratings were micro-machined into these materials using a novel anamorphic lens design and an automated x, y, z linear stage to control the sample position. The anamorphic lens reduced the circular laser beam distribution to a 2.5 micron gratings were manufactured for various laser energies, number of laser pulses, and grating line spacing using a direct write process. Single and multi-pulse femtosecond radiations are shown to lead to permanent index of refraction changes from the surface to approximately 10 mnicron below the surface of these bulk materials. Each grating was analyzed visually using a visible microscope and analytically by measuring the diffraction efficiency to determine the most efficient grating. Raman spectroscopy, atomic force microscopy (AFM), and near field scanning optical microscopy (NSOM) results are also presented.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 2007
- Accession Number
- ADA473982
Entities
People
- Angela Campbell
- Chris Brewer
- Don Dorsey
- G. L. Desautels
- Marc Finet
- Matt Whitaker
- Peter Powers
- Qiwen Zhan
- Scott Ristich
- Shane Juhl
Organizations
- Air Force Research Laboratory