A package includes a tray and a cover configured to seal an open end of the tray when the cover is assembled onto the tray. The tray has a flange extending about a periphery at the open end of the tray. A continuous barrier seal is formed between the flange and the cover when the cover is assembled onto the tray, and a discontinuous sacrificial seal is also formed between the flange and the cover when the cover is assembled onto the tray. The discontinuous sacrificial seal is configured to absorb stress applied to the flange. The continuous barrier seal is disposed closer to an inner periphery of the flange than the discontinuous sacrificial seal. Holes are formed on the corners of the flange, and the holes are spaced apart from the discontinuous sacrificial seal.