Room-temperature hermetic sealing by ultrasonic bonding with Au compliant rim

We newly introduce a compliant rim to realize hermetic sealing of electronic components at low temperature. The compliant rim easily deforms under pressing load owing to its cone-shaped cross section and, therefore, intermetallic bonding can be performed at low temperature. We demonstrate the room-temperature vacuum sealing using the compliant rim made of Au with the aid of ultrasonic vibration of submicron amplitude. A test vehicle fabricated using silicon and glass showed that the air leak rate of the room-temperature sealing was well below 1 × 10^-12 Pa.m³/s, which is sufficiently low for use in vacuum packaging.