Bonding formation and gas absorption using Au/Pt/Ti layers for vacuum packaging

Area of Science:

• Materials Science
• Surface Science
• Semiconductor Manufacturing

Background:

• Achieving reliable hermetic sealing is critical for microelectronic device longevity and performance.
• Residual gases within electronic packages can lead to device degradation and failure.
• Current vacuum packaging methods can be complex and costly.

Purpose of the Study:

• To develop a metal multilayer capable of both hermetic sealing and in-situ residual gas absorption.
• To investigate the direct bonding of gold/platinum/titanium (Au/Pt/Ti) layers for packaging applications.
• To evaluate the gas absorption properties of a titanium underlayer after high-temperature annealing.

Main Methods:

• Fabrication of a metal multilayer consisting of Au/Pt/Ti layers on a wafer.
• Direct bonding of the Au/Pt/Ti layers to create a sealed package.
• Annealing the packaged assemblies at 450°C to induce thermal diffusion and gas absorption.

Main Results:

• The Au/Pt/Ti multilayer successfully achieved hermetic sealing without any leak paths.
• Annealing at 450°C facilitated the diffusion of titanium atoms to the inner surface.
• The diffused titanium layer effectively absorbed residual gas molecules within the package.

Conclusions:

• A wafer coated with Au/Pt/Ti offers a simplified approach to vacuum packaging by providing hermeticity and gas scavenging.
• The developed metal multilayer technology can enhance the reliability and simplify the manufacturing of electronic devices.
• This method presents a promising solution for advanced semiconductor packaging, reducing process complexity and cost.