Improvement of the surface roughness and optical transparency of microstructures lithographically fabricated in APEX TM glass was accomplished through a post-etch anneal. An optimal dose of UV radiation is found to be 24 J g −1 for a wavelength of 280 nm, after which etch rate in HF acid and selectivity saturate. The anneal process, while originally designed to improve the surface roughness by reflowing, can be used to join multiple structures for the creation of optically transparent three-dimensional devices. The resulting glass microstructures demonstrate an average sidewall RMS surface roughness that is reduced from 0.7 μm to 32.7 nm which is adequate for optical signal detection across a wide frequency band that includes the visible spectrum.

No abstract

Wireless communications need radio frequency links. Radio frequency spectrum is a limited and expensive resource. To help protect the privacy of frequency users and improve efficiency of radio frequency spectrum, we propose a new topic in Spectrum Engineering. Spectrum engineering is the technical skill to solve problems in spectrum management and includes private frequency licensing, Electromagnetic Compatibility (EMC), radio regulation, and spectrum planning. In this presentation fundamental of spectrum engineering with a focus on user side and privacy of channel will be covered and considered as an objective of study in courses, such as communications systems and wireless communications.

No abstract

No abstract