Abstract: A photolithographic mask comprises a first plurality of image segments etched into a mask substrate to a first level imparting a predetermined phase shift with respect to electromagnetic radiation of a predetermined frequency, preferably a 90° phase shift, and a second plurality of image segments etched into the mask substrate to a second level imparting a phase shift of 180° more or less than the phase shift of the first plurality of image segments with respect to the predetermined electromagnetic radiation, preferably a 270° phase shift. The first and second segments are disposed adjacent each other on a substrate and positioned such that an intersection of the predetermined electromagnetic radiation passing through the segments causes printable images to be created below the substrate when exposed to the predetermined electromagnetic radiation.

Abstract: A patterned mask and method of forming a patterned mask over a substrate, comprising forming a first resist layer over the substrate, forming a second resist layer over the first resist layer, patterning the first resist using energy selective to the first resist layer to form a first patterned resist, and patterning the second resist using energy selective to the second resist layer to form a second patterned resist, wherein the first patterned resist and the second patterned resist form the patterned mask.

Abstract: A method for detection of a photomask defect. The method comprises the steps of applying a contrast-enhancing coating on the photomask and optically inspecting the photomask for defects. The contrast-enhancing coating may be copper, aluminum, molybdenum silicide, or any material capable of altering the reflectivity or transmissivity of defects.

Abstract: A two-step method for eliminating transmission errors in alternating phase-shifting masks is described. Initially, the design data is selectively biased to provide a coarse reduction in the inherent transmission error between features of different phase, size, shape, and/or location. During fabrication of the mask with the modified data, residual transmission errors are then eliminated via the positioning of the edges of the etched-quartz trenches which define the phase of a given feature to a set location beneath the opaque chrome film. Application of feedback, in which the aerial image of the mask is monitored during the positioning of the etched-quartz edges, provides additional and precise control of the residual transmission error.

Abstract: A lithographic patterning method and mask set using a phase shift trim mask having mask dimensions increased in block size so as to remove previous exposure defects.

Abstract: A method of forming a substantially defect-free mask for optical and phase-shift lithography. The method involves depositing a transfer layer on a mask layer deposited on a transmissive substrate, forming in the transfer layer a mask image to be defined in the mask layer, inspecting the image formed in the transfer layer, repairing the image formed in the transfer image, and transferring the corrected image from the transfer layer into the mask layer. The repair of the transfer layer is accomplished by removing unwanted portions of the transfer layer followed by filling any unwanted voids therein with a selected material. Preferably, the fill material has the same desirable etching and/or optical characteristics as the surrounding transfer layer. However, any material that is substantially opaque to the radiation used to transfer the image from the transfer layer to the mask layer can be successfully employed.

Abstract: An attenuating, phase-shift, semiconductor fabrication mask having recessed attenuating and phase-shifting regions that is not susceptible to phase defects in the printing regions of the mask. This desirable result is accomplished by not altering the surface of the fully transmissive regions of the mask and by recessing the attenuating regions of the mask relative to the fully transmissive regions.A method of forming the recessed attenuated phase-shift mask is also included. The process begins by forming recesses in the regions of the mask substrate where phase-shifting is desired and back filling these recessed regions with a selected thickness of attenuating material so that the attenuation effect of the deposited material together with the depth of the recess co-act to shift the light approximately 180.degree. (.pi. radians) from the light transmitted through the adjacent transmissive regions of the mask to create by destructive interference a sharp delineation at the edges of the projected mask image.

Abstract: A method of forming rim type phase-shift lithography mask (140) involving backside overexposure of a positive resist layer (130) overlying a patterned light-blocking layer (120). By subjecting the resist layer to electromagnetic radiation (132) (e.g., broad band UV) transmitted via the backside (115) of the mask substrate (112), portions (134) of the resist layer extending from peripheral edges of the light blocking layer inwardly a selected distance are activated. After developing activated portions of the resist layer, the "pull back" of the resist layer is transferred to the underlying light blocking layer by anisotropically etching portions of the light blocking layer not covered by the resist layer, thereby forming the desired rim structure.