Large-scale anodic bonding mediated by a liquid tin solder

Large area seals were prepared between a metal foil frame (Fe-Ni alloy with 48 wt% Ni) and a 901 × 814 mm2 glass pane through the simultaneous application of activated liquid tin solder anodic bonding and soft soldering. An experimental facility including a liquid solder injector was built. Prototype seals were produced with tin solder alloys with variable Al contents and the hermiticity and interface integrity was determined. Solder alloys with an Al content of 112.5 ppm resulted in the strongest adhesion forces, broadly consistent with a previous study at the laboratory scale. The resulting prototypes consist of a bonded area of ∼450 cm2 along the perimeter of a 0.73 m2 glass pane and display consistently strong bonds for sections over a meter in length, demonstrating that activated liquid solder anodic bonding is not restricted to small-area applications.