Abstract: A method includes the steps of: providing a mold substrate and a cover substrate that are bonded to each other, wherein a surface region of the mold substrate and/or of the cover substrate is structured so as to form an enclosed cavity between the cover substrate and the mold substrate; tempering the cover substrate and the mold substrate so as to decrease the viscosity of the glass material of the cover substrate, and providing an overpressure in the enclosed cavity compared to the surrounding atmosphere so as to cause, on the basis of the decreased viscosity of the glass material of the cover substrate and the overpressure in the enclosed cavity compared to the surrounding atmosphere, bulging of the glass material of the cover substrate starting from the enclosed cavity up to a stop area, spaced apart from the cover substrate, of a stop element so as to acquire a molded cover substrate with a cap element; and removing the stop element and the mold substrate from the molded cover substrate.

Abstract: The present invention is directed to a method for testing the leakage rate of an encapsulated device comprising the step: bombing the device with a neon and/or argon atmosphere using a bombing pressure of at least more than environmental pressure and measuring the quality factor before and after bombing. Preferably, the bombing time is about 10 to 100 hours, and the bombing pressure is 1.5 to 100 bar, more preferably 1.5 to 5 bar and most preferably about 4 bar. With this test, the leakage rate of fine leaks of the device may be determined.

Abstract: The present invention is directed to a method for testing the leakage rate of an encapsulated device comprising the step: bombing the device with a Neon and/or Argon atmosphere using a bombing pressure of at least more than environmental pressure and measuring the quality factor before and after bombing. Preferably, the bombing time is about 10 to 100 hours, and the bombing pressure is 1.5 to 100 bar, more preferably 1.5 to 5 bar and most preferably about 4 bar. With this test, the leakage rate of fine leaks of the device may be determined. This test is helpful in determining statistical surface contaminations or defects caused by wafer processing that affect the seal integrity just enough to cause shorter lifetimes. Further, dicing, die assembly and transfer molding may also introduce physical defects which may be detected with the present method. Finally, the inventive test method may be useful for process optimization: Hermeticity tests are a great help to optimize sealing processes.