## Doctoral Dissertations

Summer 1998

Dissertation

#### Degree Name

Doctor of Engineering (DEng)

#### Department

Micro and Nanoscale Systems

A manufacturing process for an optical fiber ferrule mold insert with twelve channels has been established. This research project presents mask design, mask fabrication, deep X-ray lithography exposure, resist developing, nickel electroforming, as well as surface finishing to attain the final result. Deep X-ray mask fabrication methods are explored, including mechanically machined masks, micro-EDM masks, and E-beam written masks. The exposures to pattern resists and electroforming to fabricate nickel molds up to 500 $\mu$m thickness are reported in this study. Nickel structures for the optical fiber ferrule insert with twelve channels made by electroforming are the final products. A practical method to finish the microstructure surface is presented. Channels with precision $-$0.0/+0.5 micron and pitch alignment with 0.25 micron are accomplished to satisfy the requirements of the research sponsor for inserting standard optical fibers (125 $\mu$m in diameter).