摘要:
Flare of an imaging system is measured using resist by employing the imaging system to directly expose a first part of the resist at an image plane of the imaging system to a first dose of radiation and to indirectly expose a second part of the resist as a result of flare. The imaging system exposes the second part of the resist to a second dose of radiation. Flare of the imaging system is determined from a pattern that is formed in the second part of the resist.
摘要:
A method and system for reducing the computation time required to apply position-dependent corrections to lithography, usually mask, data is disclosed. Optical proximity or process corrections are determined for a few instances of a repeating cluster or object, usually at widely separated locations and then interpolating the corrections to the other instances of the repeating cluster based on their positions in the exposure field. Or, optical proximity corrections can be applied to the repeating cluster of objects for different values of flare intensity, or another parameter of patterning imperfection, such as by calculating the value of the flare at the location of each instance of the repeating cluster, and interpolating the optical proximity corrections to those values of flare.
摘要:
A method for synthesizing a photomask data set from a given target layout, including the following steps: (a) providing a set of target polygons for the target layout; (b) fitting a smooth curve to a target polygon of the set of target polygons, the curve having a set of etch-target points; (c) moving the etch target points according to a model of an etch process to produce a set of lithography-target points; and (d) synthesizing a photomask data set based on a model of a lithography process and the set of lithography-target points.
摘要:
First and second exposures of a mask onto a wafer are performed such that the exposure field of the second exposure partially overlaps the exposure field of the first exposure. A characteristic of a set of features is determined, and a value of a parameter of an optical proximity correction model is determined. An alignment feature can be used to align a measurement tool. In yet another embodiment, pupil intensity distribution of an imaging system is measured by exposing an image field of a radiation detector with a bright feature, positioning the detector at a distance away from the image plane, and exposing the image field of the detector with a bright feature, resulting in a cumulative exposure of the image field of the detector from the two exposures. A characteristic of a spatial pattern in the cumulative exposure of the image field of the detector is then determined.
摘要:
A method for generating an OPC model is provided which takes into consideration across-wafer variations which occur during the process of manufacturing semiconductor chips. More particularly, a method for generating an OPC model is provided which takes into consideration across-wafer variations which occur during the process of manufacturing semiconductor chips based on the parameters of test patterns measured at the “wafer sweet spots” so as to arrive at an accurate model.
摘要:
A method to self-align a lithographic pattern to a workpiece, the method including the steps of obtaining a workpiece having a predetermined pattern of features; modifying at least some of the features so that when a photoresist material is applied to the pattern, there is a substantial difference in reflectivity between two adjacent features, at least one of which has been modified; applying a photoresist material; masklessly exposing the photoresist material; developing the photoresist material, the substantial difference in reflectivity of the two adjacent features causing the developed photoresist material to reveal one adjacent feature but not the other.
摘要:
A system, method and program product that implement a design object that automatically provides compliance to alternating phase shifted mask (altPSM) rules are disclosed. The invention implements a design object that is used during layout to indicate a phase-shiftable design feature in the layout. Each design object includes a base shape indicative of the feature to be ultimately created and two different type phase shape identifiers that identify the requisite mask area and color of phase-shift required for that base shape. Each phase shape identifier is assigned to a portion of the base shape. During layout, overlapping placement of design objects is not allowed if the placement requires overlapping phase identifiers of the same type. Alternatively, placement is allowed where the phase identifiers of different type are separated by a minimum distance from each other defined by a buffer of the design object.
摘要:
A method of making at least one feature on an object having an upper surface, comprising the steps of:1. applying a layer of a photoresist having an initial thickness to the upper surface;2. exposing the layer of photoresist to a first dosage of light having a first intensity for a first predetermined period of time, such that at least a portion of the upper surface has a thickness that is at most equal to the initial thickness; and3. exposing the layer of photoresist to a second dosage of light having a second intensity for a second predetermined period of time, such that at least a subset of the portion of the upper surface exposed by the first dosage of light is exposed by the second dosage of light.
摘要:
Damage to the rim of a semiconductor wafer caused by etching processes is reduced by forming a rim of photoresist or other material around the outer edge of the wafer that has a thickness such that images projected on the rim are sufficiently out of focus that they do not develop, so that etching takes place only in the interior.