Abstract: In a method for manufacturing a dual shallow trench isolation structure, a substrate is provided, and a mask layer is formed on the substrate. The mask layer is patterned by using a photomask to form at least one first hole and at least one second hole in the mask layer, in which a depth of the at least one first hole is different from a depth of the at least one second hole. The mask layer and the substrate are etched to form at least one first trench having a first depth and at least one second trench having a second depth, in which the first depth is different from the second depth. The remaining mask layer is removed. A first isolation layer and A second isolation layer are respectively formed in the at least one first trench and the at least one second trench.

Abstract: In a method for manufacturing a dual shallow trench isolation structure, a substrate is provided, and a mask layer is formed on the substrate. The mask layer is patterned by using a photomask to form at least one first hole and at least one second hole in the mask layer, in which a depth of the at least one first hole is different from a depth of the at least one second hole. The mask layer and the substrate are etched to form at least one first trench having a first depth and at least one second trench having a second depth, in which the first depth is different from the second depth. The remaining mask layer is removed. A first isolation layer and A second isolation layer are respectively formed in the at least one first trench and the at least one second trench.

Abstract: A method comprising providing at least one dielectric layer above a semiconductor substrate, the at least one dielectric layer having a top surface and a bottom surface; forming a photoresist layer on the top surface of the at least one dielectric layer; providing a single photomask having at least one first pattern corresponding to a conductive via and at least one second pattern corresponding to a conductive trace; patterning the photoresist layer using the single photomask, for forming a trench in the photoresist corresponding to the conductive trace and an opening in a bottom surface of the trench corresponding to the via with a single photo exposure step; and etching the dielectric through the photoresist layer to form the trench and via therein. This application also relates to photomasks for use in the methods of this application.