Abstract: A method for pressing an identification mark into a ceramic lid of an integrated circuit package. The method includes the steps of mixing an oxide material with a binder to create a powder. The powder is then placed into a mold and pressed into a substrate with a press. The bottom of the press has raised or recessed portions arranged in the pattern of an identification mark. The raised or recessed portions press the mark into the powder when the powder is pressed into a substrate. The substrate is then removed from the mold and heated to harden the powder into a ceramic lid. The recessed or raised indicia are relatively deep and wide so that it is difficult to remove the mark with known grinding or laser techniques.

Abstract: A lid for sealing a semiconductor package containing a semiconductor chip, a semiconductor package making use of the lid, and a method for producing the lid. The lid has a solder layer along the peripheral side of a ceramic plate. The solder layer has a portion of an increased solder thickness and a portion of a reduced solder thickness extending along the peripheral direction. When sealing the semiconductor package, a gas confined within the inside of the semiconductor chip mounting site of the package substrate may be discharged from the semiconductor package for realizing hermetic sealing.