# Presentation: 666289

## Vacuum Deposition Thin Film Coatings Facility at Lab 7

- Eileen Hahn

- Particle Physics Division Technical Centers

## Services Offered

- Optical fiber and connector polishing
- Fiber splicing
- Evaporated and sputtered coatings, especially fiber mirroring
- Cleaning and bake-out for UHV parts
- High temperature vacuum furnace  (1200 C) -hydrogen degassing of SRF cavities
- RGA and out-gassing studies
- Plasma etching

- Particle Physics Division Technical Centers

## High Output Production History of Optical Fiber Polishing & Mirroring

- CDF Plug and Muon Tracker
- CMS HCAL
- CREAM
- D0 Central Fiber Tracker, VLPC Production, ICD, Forward Pre-Shower & Forward Proton Detectors
- NASA-GLAST
- PHENIX
- STAR-EMC Fiber barrel & End cap
***Polished >1,000,000 fibers ***
*** ******Mirrored >500,000 fibers***

- Particle Physics Division Technical Centers

## Polish and Mirror Processing of Optic Fibers

- “Ice Polishing”
- Quality Control
- Preparation for Mirroring
- Sputter Deposition in Vacuum
- Optional UV epoxy coating of mirrored ends
- Transport Packaging

- Particle Physics Division Technical Centers

## “Ice Polishing” of Optical Fibers

**“****Ice Polishing” of Optical Fibers**

- 2 programmable diamond polishers built at Fermilab specially engineered to reduce/eliminate vibration
- Frozen water clamps fibers eliminating chatter and lubricates allowing for high rpm and slow feed recipe for high quality polish
- Fabricate special hex fixtures to hold fiber bundles normal to cut
- Individual Fibers ranging from 0.35mm to 2mm diameters
- Round and square cross section fibers
- Setup for fiber lengths from 5cm to 10m
- Rate of production is dependent on diameter

- Particle Physics Division Technical Centers

## Quality Controls

- Daily testing procedure of polishing results
- Attention to machine maintenance
- Log keeping
- Visual inspection of fiber polish under magnification
- Monitoring of sputter process, tracking identification and visual inspection
- Reflectivity testing has been handled by the experimenters –Reflectivity rates have ranged from 80% to 90% consistently

- Particle Physics Division Technical Centers

## Prep for Mirroring of Optical Fiber ends

- Amber room lights for light sensitive fibers (such as 3HF)
- Experienced handling and cleaning of delicate fibers
- All fibers handled with CR100 rated gloves

- Particle Physics Division Technical Centers

## Sputter Deposition System for Aluminizing fiber ends

- Particle Physics Division Technical Centers

## Fiber Mirroring Sputter Process 

**Fiber Mirroring Sputter Process **

- 2 vacuum systems specifically built and dedicated to optical fiber sputtering
- Varying diameters & lengths can be mirrored - systems were designed to accommodate production lengths of 2.5 meters.  Auxiliary extension will handle 3.5 meter long fibers
- Sputter load dependent on diameter - typically 500 to 2000 fibers per pump down per unit
- 99.999% chemically pure aluminum target
- Very pure argon gas “Sputtering Grade” used
- 3000 Angstrom thick coating monitored with oscillating quartz crystal sensor
- Magnetron sputtering gun driven by DC power supply

- Particle Physics Division Technical Centers

## Summary

- We have been providing this service over the last 15 years
- Supporting
- FNAL experiments
- University R&D
-  DOE and International Facilities
- On time and on budget!!

- Particle Physics Division Technical Centers