Rapid evaluation of hermetic seals in microelectronic packages using shearography

One possible failure of microelectronic devices is due to leakage resulted from imperfect hermetical seal in mircochips and microelectronic packages. This paper presents an optical technique for rapid evaluation of hermetics seals. It is based on measuring package deformation with shearography. The package under test is stressed by an external pressure change and the deformation of the test package's Lid is measured with shearography. With the pressure change maintained, the lid of a perfectly sealed package will remain deformed while a leaky package will not hold the deformation that can be monitored by shearography. The proposed process of leaking testing is very fast and practical.