National Ignition Facility (NIF) Small Optics Summit
Introduction
Horst D. Bissinger
September 10, 1998
Cleaning Deliverable NIF Sub-Systems
Now that you have made the best opto-mechanical part in the world, how will you protect and ship the part in one piece?
- We all know, if you can reduce handling, less contamination will occur
- Cleanliness begins during fabrication
- Bevels and edges should be inspection polished
- Coating chambers should be backfilled with clean, dry air (or dry nitrogen)
- Handle all optics in a clean environment (level 50 or 1000)
- Optical substrates should be exposed to other levels to an absolute minimum
- Packing and shipping of optics should be managed in the same spirit
- Mechanical assemblies
- Cleanliness, particulate, and NVR is as critical as the optic itself
- Pre-aligned opto-mechanical assemblies must also meet the ASTM standard vibration and thermal transportation specifications
Recommended Packing Material
- For loose optical components we provide reusable containers molded with PET-G type material
- PET-G is a copolyester, which is a clear, amorphous polymer, glycol-modified polyethylene terephthalate (PET)
- This is a NASA designed and Eastman Kodak developed plastic material
- This material will protect coated surfaces under extreme circumstances, such as out-gassing in temperature
- Extremely shock resistant and recyclable
- For non-glass surfaces we recommend capping the optical surfaces with PET-G caps and skin vacuum pack or back-filled dry nitrogen design
Preparation for Shipment and Delivery
All optically exposed surfaces shall be covered with clean protective covers to protect them from damage during normal shipping and handling.
Delivery preparation:
- Clean and package the item to maintain cleanliness and to prevent damage during handling and shipment to LLNL as specified on the purchase order
- All components are to be prepared and handled in accordance with the requirements specified in MEL98-014
- Each component or large part shall be preferably wrapped separately in clean room quality nylon/polyethylene bag (0.15 mm minimum thickness)
- The bags shall be heat-sealed
PET-G Containers
PET-G Containers to Hold Round or Odd-Shaped Loose Optical Substrates
Different Shapes of PET-G Containers
Shipping Containers Semi-Custom Made for a Specific Item
Cleanliness Requirements
- Level 50 containers are cleaned using:
- CO2 sno spray
- High pressure water spray
- Ultrasonic aqueous cleaning system
- Level 1000 containers are cleaned using:
- Wipe cleaning with high purity ethanol
Cleaning Processes - MEL Guidelines
for Removing Organics, Soil, Dust and Scale
Fabrication and Handling of NIF Laser Components and Structures
Cleaning of Cast Aluminum Alloy Components for NIF
Cleaning of Wrought Aluminum Alloy Components for NIF
Gross High-Pressure Water Wash for NIF Components
Cleaning of 300 and 400 Series CRES Steel Components for NIF
Cleaning of Copper and Copper Alloy Components for NIF
High Temperature Bake-Out to Remove Volatile Organics for NIF
Handling of Components for NIF and Guidelines for Creating and Maintaining Clean Area
for Achieving < 1246C Level 100A Cleanliness
Precision CO2 Snow Cleaning for NIF Components
Precision High-Pressure Water Wash for NIF Components
Precision Ultrasonic Cleaning for NIF Components
Surface Cleanliness Validation by Swiping for NIF Components
Precision Surface Wiping for NIF Components
Precision Ultrasonic Cleaning in OAB for NIF
Non-Volatile Residue Validation for NIF Components
LLNL Packing Procedure Summary
- PET-G loose glass containers are packed in multiples inside a foam packed polyethylene box and then packed in larger cardboard boxes
- Level 100 mechanical parts all need to be double wrapped.
- Nylon bag on inside
- Polyethylene bag on the outside
- Small assemblies use uniquely designed PET-G reusable containers
- Larger assemblies have uniquely designed PET-G end-caps
- Some optical substrates and components mounted in assemblies need to maintain a cleanliness Level 50 per Mil Std. 1296C
