Abstract: A method for predicting pattern critical dimensions in a lithographic exposure process includes defining relationships between critical dimension, defocus, and dose. The method also includes performing at least one exposure run in creating a pattern on a wafer. The method also includes creating a dose map. The method also includes creating a defocus map. The method also includes predicting pattern critical dimensions based on the relationships, the dose map, and the defocus map.

Abstract: A method for predicting pattern critical dimensions in a lithographic exposure process includes defining relationships between critical dimension, defocus, and dose. The method also includes performing at least one exposure run in creating a pattern on a wafer. The method also includes creating a dose map. The method also includes creating a defocus map. The method also includes predicting pattern critical dimensions based on the relationships, the dose map, and the defocus map.

Abstract: A system and methods are provide for modeling the behavior of a lithographic scanner and, more particularly, a system and methods are provide using thresholds of an image profile to characterize through-pitch printing behavior of a lithographic scanner. The method includes running a lithographic model for a target tool and running a lithographic model on the matching tool for a plurality of different settings using lens numerical aperture, numerical aperture of the illuminator and annular ratio of a pattern which is produced by an illuminator. The method then selects the setting that most closely matches the output of the target tool.

Abstract: A modeling technique is provided. The modeling technique includes inputting tool parameters into a model and inputting basic model parameters into the model. The technique further includes generating a simulated, corrected reticle design using the tool parameters and the basic model parameters. An image of test patterns for an integrated circuit is compared against the simulated, corrected reticle design. A determination is made as to whether a difference between the simulated, corrected reticle design and exposure results of the image of the test patterns (?1) is less than a predetermined criteria (?1). The technique further includes completing the model the difference between the simulated, corrected reticle design and the exposure results of the image of the test patterns is less than the predetermined criteria.

Abstract: An automated signature detection system and method of use and, more particularly, a predictive modeling component configured to accurately predict maintenance events for optical elements used in lithographic tools. The system comprises at least one module configured to analyze data associated with power illumination at a surface. The at least one module also is configured to fit a curve to the analyzed data using an exponentially based decay model.

Abstract: A method for matching a first OPE curve (700) for a first exposure apparatus (10A) used to transfer an image to a wafer (28) to a second OPE curve (702) of a second exposure apparatus (10B). The method can include the step of adjusting a tilt of a wafer stage (50) that retains the wafer to adjust the first OPE curve. As provided herein, the first exposure apparatus (10A) has the first OPE curve (700) because of the design of the components used in the first exposure apparatus (10A), and the second exposure apparatus (10B) has a second OPE curve (702) because of the design of the components used in the second exposure apparatus (10B). Further, the tilt of the wafer stage (50) can be selectively adjusted until the first OPE curve (700) approximately matches the second OPE curve (702). With this design, the two exposure apparatuses (10A) (10B) can be used for the same lithographic process.

Abstract: A system and method of calculating estimated image profiles. The system and method includes providing lens characteristic data and performing simulation calculations for various levels of aberration components using the lens characteristic data. A response surface functional relation is built between selected variables of the lens characteristics, in particular the lens aberration components, and the Image Profile using the simulation calculations. Evaluation is then performed on the arbitrary specified aberration values of a lens in relation to the response surface functional relations to provide a calculated estimate of the Image Profile for the specified aberration values. A machine readable medium and exposure apparatus are also provided.

Abstract: A method for matching a first OPE curve (700) for a first exposure apparatus (10A) used to transfer an image to a wafer (28) to a second OPE curve (702) of a second exposure apparatus (10B). The method can include the step of adjusting a tilt of a wafer stage (50) that retains the wafer to adjust the first OPE curve. As provided herein, the first exposure apparatus (10A) has the first OPE curve (700) because of the design of the components used in the first exposure apparatus (10A), and the second exposure apparatus (10B) has a second OPE curve (702) because of the design of the components used in the second exposure apparatus (10B). Further, the tilt of the wafer stage (50) can be selectively adjusted until the first OPE curve (700) approximately matches the second OPE curve (702). With this design, the two exposure apparatuses (10A) (10B) can be used for the same lithographic process.

Abstract: A system and method of calculating estimated image profiles. The system and method includes providing lens characteristic data and performing simulation calculations for various levels of aberration components using the lens characteristic data. A response surface functional relation is built between selected variables of the lens characteristics, in particular the lens aberration components, and the Image Profile using the simulation calculations. Evaluation is then performed on the arbitrary specified aberration values of a lens in relation to the response surface functional relations to provide a calculated estimate of the Image Profile for the specified aberration values. A machine readable medium and exposure apparatus are also provided.

Abstract: Methods for using critical dimension test marks (test marks) for the rapid determination of the best focus position of lithographic processing equipment and critical dimension measurement analysis across a wafer's surface are described. In a first embodiment, a plurality of test mark arrays are distributed across the surface of a wafer, a different plurality being created at a plurality of focus positions. Measurement of the length or area of the resultant test marks allows for the determination of the best focus position of the processing equipment. Critical dimension measurements at multiple points on a wafer with test marks allow for the determination of process accuracy and repeatability and further allows for the real-time detection of process degradation. Using test marks which require only a relatively simple optical scanner and sensor to measure their length or area, it is possible to measure hundreds of measurement values across a wafer in thirty minutes.

Abstract: A test mark, as well as methods for forming and using the test mark to facilitate the measurement of the critical dimensions of etched features in semiconductor and other wafer level processing is described. The test marks may be used to characterize, calibrate and/or monitor etch performance. Test marks are defined by imaging (typically at partial exposures) overlapping, angularly offset lines in a resist that covers a layer to be etched. The lines preferably have line widths that are equal (or related) to a critical dimension of interest. After the resist is developed and otherwise processed, the layer is etched as appropriate, thereby creating the test marks. The test marks are then imaged to facilitate the determination of a geometric parameter of each mark. Most commonly, the geometric parameter determined relates to the area of the mark and/or the length of its major dimension.

Abstract: A method for diagnosing a lithographic tool. The method includes developing digitalized images of at least one wafer pattern with different exposure doses and assembling the digitized images into a pupilgram. The at least one function is of a known illuminator behavior of the lithographic tool is modeled. The pupilgram is fitted to the modeled function to determine whether a behavior associated with the pupilgram is within predetermined limits of illuminator behavior to diagnosis imperfections in the illuminator behavior. One technique applied to the illuminator analysis consists of evaluating the dose transmitted (by direct calculation) by the lens for a given input pupilgram (or set of pupilgram basis functions), a given pattern size and pitch, and a defined lens NA, is described.

Abstract: Methods and apparatus for enabling both isolated and dense patterns to be accurately patterned onto a wafer are disclosed. According to one aspect of the present invention, an illumination system that is suitable for use as a part of a projection tool includes an illumination source and an illuminator aperture. The illuminator aperture has a center point and an outer edge, and also includes a first pole and a second pole. The first pole is defined substantially about the center point, and the second pole is defined substantially between the first pole and the outer edge of the first pole. The illumination source is arranged to provide a beam to the illuminator aperture.

Abstract: Methods and apparatus for enabling both isolated and dense patterns to be accurately patterned onto a wafer are disclosed. According to one aspect of the present invention, an illumination system that is suitable for use as a part of a projection tool includes an illumination source and an illuminator aperture. The illuminator aperture has a center point and an outer edge, and also includes a first pole and a second pole. The first pole is defined substantially about the center point, and the second pole is defined substantially between the first pole and the outer edge of the first pole. The illumination source is arranged to provide a beam to the illuminator aperture.

Abstract: Apparatus for performing measurement of a dimension of a test marked formed by overlapping feature imaged onto a an image forming layer of a semiconductor wafer and the calculation of the critical dimensions of the features from test mark. This is used in semiconductor processing. Also included is software configured to program a measurement device to perform the measurement and calculation of the dimension of a test mark.

Abstract: Variation in position of test marks formed of overlapping exposed features imaged by an imaging structure such as that of a lithography tool are characterized at high speed and with extremely high accuracy by imaging test marks formed in resist or on a target or wafer by a lithographic process, collecting irradiance distribution data and fitting a mathematical function to respective portions or regions of output data corresponding to a test mark of a test mark pattern such as respective maxima or minima regions or other regions of the irradiance distribution data to determine actual location and shift of position of respective patterns of test marks. Metrology fields are formed of patterns of test marks on test wafers or production wafers preferably including a critical dimension exposed at different focus distances and/or illumination conditions to capture position/aberration data for the imaging structure.

Abstract: Methods for using critical dimension test marks (test marks) for the rapid determination of the best focus position of lithographic processing equipment and critical dimension measurement analysis across a wafer's surface are described. In a first embodiment, a plurality of test mark arrays are distributed across the surface of a wafer, a different plurality being created at a plurality of focus positions. Measurement of the length or area of the resultant test marks allows for the determination of the best focus position of the processing equipment. Critical dimension measurements at multiple points on a wafer with test marks allow for the determination of process accuracy and repeatability and further allows for the real-time detection of process degradation. Using test marks which require only a relatively simple optical scanner and sensor to measure their length or area, it is possible to measure hundreds of measurement values across a wafer in thirty minutes.

Abstract: Increased accuracy of measurement of variation of a critical dimension is achieved through measurement of area of a test mark by detection of intensity of radiation such as broadband light with which at least a portion of a test mark is imaged. The test mark is preferably formed by partial lithographic exposures of overlapping features, preferably lines having a width approximating a critical dimension of interest and at a shallow angle to each other such that the test mark has the shape of a parallelogram or rhombus.

Abstract: A retention system for securing a stage mirror to the wafer stage of a semiconductor manufacturing device includes at least one first bracket and at least one second bracket. The retention system rigidly secures the stage mirror to the wafer stage during movement of the wafer stage to reduce positional measurement errors. The at least one first bracket has a substantially planar first contact surface for engaging the reflective surface of the mirror. The first contact surface is a finished aluminum surface, which does not scratch the mirror surface. The at least one first bracket is formed with a gusset providing increased stiffness in the direction of movement of the wafer stage. The at least one second bracket includes an actuator for moving a substantially planar second contact surface into engagement with a rear surface of the mirror. In one embodiment, the actuator is a threaded fastener and the second contact surface is a finished polyimide resin tip.

Abstract: Methods and apparatus for enabling both isolated and dense patterns to be accurately patterned onto a wafer are disclosed. According to one aspect of the present invention, an illumination system that is suitable for use as a part of a projection tool includes an illumination source and an illuminator aperture. The illuminator aperture has a center point and an outer edge, and also includes a first pole and a second pole. The first pole is defined substantially about the center point, and the second pole is defined substantially between the first pole and the outer edge of the first pole. The illumination source is arranged to provide a beam to the illuminator aperture.