<title>High-throughput planer glass coating using Laser Reactive Deposition (LRD)</title>

Abstract

Planar Lightwave Circuit (PLC) technology has been considered as a promising route to integrate a greater number of channels and more optical functionalities onto a small foot print, enabling smaller device sizes and lower costs of manufacturing by using existing semiconductor process technologies. Among several planar technology platforms, silica-on-silicon technology comprised of a silica higher index core and lower index clad has taken the lead in this direction. One of the major advantages of silica based PLC technology is its relative ease to couple to a single mode silica fiber because of a close match of the index and dimensions of the waveguide core of planar chip and fiber. In this structure, to completely confine and guide light signals, the silica layer stack, including lower clad, core and top clad can be as thick as 20 -40 microns, in which the core layer thickness is around 6 -8 micron. This has presented a major challenge to several major silica film deposition technologies including CVD, FHD, PVD, and Sol-Gel processes. In addition to basic requirements for optical quality of the glass film, low cost manufacture also demands a high deposition rate to reduce process costs in the fabrication of these planar chips. In this paper, we present a high throughput and planar glass coating technology to lay down doped and undoped glass films at a unprecedented rates. The technology is comprised of a laser reactive deposition (LRD TM ) process developed based on our nanoscale particle manufacture (NPM TM ) methods pioneered by NanoGram Corporation. We report results on planar glass films deposited using this technology and describe the concepts employed using this technology in manufacturing. Furthermore, we will compare it with various existing glass film deposition technologies.

High-Rate Deposition Of Rare-Earth Doped Silicate Nanoparticles For Porous & Dense Optical Films

“…The LRD™ process combines LP with a deposition mechanism in which the nanoparticles impinge upon and adhere to a substrate located above the LRZ. Translating the substrate perpendicularly to the LRZ yields a coated planar preform comprised of packed nanoparticle soot adhered to the substrate [5,6].…”

“…The LRD™ approach has advantages over FHD in the linear scalability of the particle plume along with a great degree of process flexibility and control [5]. These attributes yield greater composition and thickness uniformity.…”

“…These attributes yield greater composition and thickness uniformity. In addition, LRD™ processing has cost and compositional advantages over CVD [5]. This work describes using LRD™ technology to produce active glass films (e.g.…”