Abstract: A pillow cover assembly includes a plurality of layers of pillow sheets bound together on one edge that can be flipped around the bound end like a book; an attachment system configured to attach the pillow sheets to pillow or a pillow case configured to house the pillow, wherein the attachment system is a plurality of straps with fasteners at each end; and a holding mechanism attached to a bottom layer of the plurality of layers of pillow sheets. Each layer of pillow sheets above the bottom layer has a hole in a position corresponding to a point of attachment of the holding mechanism on the bottom sheet, where the holding mechanism goes through the holes, and each layer of pillow sheets is longer than the one below.

Abstract: A semiconductor device includes a first layer, first and second active areas disposed on the first layer; a trench disposed between the first and second active areas, an insulating oxide that fills the trench to a level below a surface of the first and second active layers, and a nitride cap disposed on top of the insulating oxide so that the first and second active areas can be cleaned without damaging the insulating oxide. A top surface of the nitride cap in regions adjacent to the first and second active areas is aligned with a top surface of the first and second active areas, a top surface of the nitride cap in a center region of the nitride cap is stepped below the top surface of the adjacent regions, and a void is formed between the top surface regions adjacent to the first and second active areas.