Bonding technologies adapted to glass and glass-ceramics

Objective

Development of “adapted“ bonding technologies for glass and glass-ceramics using water based silicate solutions or no additives at all (“Direct Bonding“) by applying suitable surface activation processes before assembly in a vacuum environment.

 

Pre-conditions

  • Materials with a high SiO2 content
  • Surfaces highly plane (or otherwise conform),
  • flatness at least λ /10 PV* 
  • Extremely smooth (polished) surfaces, roughness < 1 nm RMS*

* λ:        wavelength (632 nm)
   PV:      peak-to-valley
   RMS:   root-mean-square

 

Bond characteristics

  • Full transparency (bonding area is "invisible”)
  • No uncontrolled creep/drift under mechanical load
  • No outgassing at elevated temperatures
  • No stress from thermal mismatch (for identical materials)
  • Assembly of individual parts “accurate to gage blocks“

 

Applications

  • UV, VIS and IR optics (transmission and reflection)
  • Laser applications  
  • Space applications
  • Lithography and precision engineering applications