Wafer-level hermetic vacuum micro-packaging technology for IR detector applications

Abstract

A low-cost low temperature wafer-level vacuum micropackage has been developed exhibiting an equivalent flow rate of 3.8x10 -14 Torr.L/sec for storage at 80 °C.

Vacuum quality evaluation for uncooled micro bolometer thermal imager sensors

“…1). (4,5) and is defined by the geometrical bolometer leg design, with the leg area A, the leg length l and the material specific thermal conductivity k of the different material layers.…”

“…Independently from which packaging and bonding process is chosen, the increasing internal pressure directly leads to performance reductions of the IRFPA. The influence of changing pressure on the imager performance was also investigated in [2][3][4]. For that reason it is necessary to measure and track the internal pressure level of the package to investigate and assure the quality and reliability of the IRFPA.…”

Investigation on Performance and Vacuum Package of MEMS Infrared Focal Plane Arrays

“…Regarding the vacuum packaging, our substrate-free FPA is unlike other optical or IR MEMS devices [5], [6], [9], [10]. There are two transparent windows with different materials for visible and IR light, respectively, that need to be assembled with a metal chamber.…”

“…They demonstrated that, when the internal pressure is 10 −2 torr or below, the thermal conductance by the gas inside the vacuum package is much smaller than the thermal conductance of the solid part of the bolometer [3]. Other works such as [4]- [6] were also focused on the relationship between the vacuum and sensitivity of the bolometer, indicating that low air pressure in the package contributes to the sensitivity. The relationship between response time and air pressure, however, has not been mentioned yet.…”