抄録
We have developed chip scale vacuum packaging for an uncooled IRFPA and successfully obtained excellent IR images less than 60 mK in NETD. This package consists of a device chip and a silicon lid. A 160×120 SOI diode uncooled IRFPA with a 25 μm pixel pitch is used as the device chip in this study. The size of the package is 14.5 (L)×13.5 (W)×1.2 (H) mm. The gap between the device chip and the lid is controlled by the thickness of the vacuum sealing material (solder), which is mounted by our original molten solder ejection method. Patterned thin-film getter is formed on the lid wafer. Due to the use of patterned thin-film getter, there is no need to form a cavity on the lid to allow installation of getter or to insert a spacer between the device chip and the lid. The measured pressure of the package is less than 0.5 Pa, which is sufficient for obtaining high thermal isolation. The package also passed 1000 heat cycle tests from -40 to 125°C. In this technique, only the good dies in a wafer are simultaneously packaged in chip scale. Thus, size and cost reduction of the package has been achieved.
