Abstract: A method for forming square shape images in a lithographic process is disclosed wherein a first plurality of lines running in a first direction is defined in a first, usually sacrificial, layer, and then a second resist is defined wherein the lines run in an intersecting pattern to those of the first layer, thereby creating cornered images wherever the first and second layer intersect and in the open areas between the lines. Methods are proposed for developing the square intersecting areas and the square angle areas defined by the openings. Additionally, a photomask is disclosed in which the length and width of the cornered images are independently patterned using the two-exposure process.

Abstract: A method for forming square shape images in a lithographic process is disclosed wherein a first plurality of lines running in a first direction is defined in a first, usually sacrificial, layer, and then a second resist is defined wherein the lines run in an intersecting pattern to those of the first layer, thereby creating cornered images wherever the first and second layer intersect and in the open areas between the lines. Methods are proposed for developing the square intersecting areas and the square angle areas defined by the openings. Additionally, a photomask is disclosed in which the length and width of the cornered images are independently patterned using the two-exposure process.

Abstract: A process of phase edge lithography is employed in the manufacture of very large scale integrated (VLSI) chips in which chrome images are biased on a phase edge of a phase shift mask (PSM) and the mask overexposed to compensate for the positive bias. This overexposure eliminates any residual images from the phase edge mask with minimum impact to the desired images. This simple process results in a trim-less phase edge process that takes advantage of the improved resolution and process latitude of phase edge PSMs while avoiding layout impacts caused by a trim mask or other phase edge elimination methods.