Enhanced vacuum glazing bonding strength by anodic bonding‐assisted sealing method

Abstract

A novel sealing method of vacuum glazing is introduced in this study. Anodic bonding technology was used to enhance the bonding strength of the sealant of vacuum glazing. Two sheets of plane glass were sealed by V2O5‐P2O5‐TeO2 glass powder with low glass transition temperature (339.3℃) using anodic bonding‐assisted low‐temperature sintering. Through analyzing the results of Shear Strength test, the diagram of microstructures of the sealing bond taken by a micro Super‐depth Microscopy, Scanning Electron Microscope (SEM), and Energy Dispersive Spectrometer (EDS), the best bonding treatment schedule was determined for achieving the strongest bond. The experiment results show that anodic bonding has a dramatic influence on bonding performance. When the sealing temperature and bonding time are kept constant, the shear strength of the sample increases by increasing the bonding voltage. With the bonding temperature of 470℃ and the voltage of 600 V, the air tightness of the sealed sample is 3.9 × 10−9 Pa·m3/s. The improved bonding strength can enhance life‐time of vacuum glazing.

Glass forming region and bonding mechanism of low‐melting V2O5–TeO2–Bi2O3 glass applied in vacuum glazing sealing

“…We have successfully fabricated durable vacuum glazing samples under the parameters of 470°C, 20 min, and 600 V, and average shear strength of the samples reached 3.42 MPa 43 . Compared with our former work, vacuum glazing fabricated under the optimal parameters possesses a higher shear strength of 4.31 MPa, and the sealing process could be finished at a lower temperature.…”

“…Figure 15 manifests the anodic‐bonding mechanism of the edge sealing of vacuum glazing. When the sample (shown in Figure 2C) was applied with voltage, oxides decomposed into cations (such as Na + , V 5+ , Te 4+ and Bi 3+ ) and oxygen ions (O 2− ) 43 . Due to the applied electric field, the cations gradually move towards the cathode, while the oxygen ions move towards the anode.…”

“…When the sample (shown in Figure 2C) was applied with voltage, oxides decomposed into cations (such as Na + , V 5+ , Te 4+ and Bi 3+ ) and oxygen ions (O 2− ). 43 Due to the applied electric field, the cations gradually move towards the cathode, while the oxygen ions move towards the anode. In order to maintain the electrical neutrality, covalent bonds, such as Si-O, V-O and Te-O, were formed at the interfaces of the low-melting glass coating and glass substrates.…”

“…Lu first adopted anodic‐bonding technique to seal the vacuum gap using In‐Sn alloy solder for fabrication of vacuum glazing 41 . Very recently, we reported the low‐melting glasses of V 2 O 5 –P 2 O 5 –TeO 2 42–43 and V 2 O 5 –P 2 O 5 –B 2 O 3 44 system were chosen as the edge sealing material for the fabrication of vacuum glazing, and the enhanced sealing performance with the assistance of anodic‐bonding method was investigated.…”