Koninklijke Philips Corporation N.v.

Vlsi Technology, Inc.

Infineon Technologies Ag

Nxp B.v.

At&t Bell Laboratories

Philips Semiconductor, Inc.

Synopsys, Inc.

Vsli Technology, Inc.

David Howard Ziger

Pierre Leroux

Sethi Satyendra

Christopher Robinett

Hunter B Brugge

Ramiro Solis

Ralf Ziebold

Frank Goodwin

Edward Dension

Steven Qian

Edward Denison

Hunter Brugge

A computer-implemented method of managing resources for multiple trial distributed processing tasks is presented. The method includes estimating an expected time needed to process each of a set of mask patterns which can be independently processed. The method further includes allocating each of the set of mask patterns to a set of processing cores in accordance with the expected time, and processing the mask patterns in accordance with the allocation, when the computer in invoked to estimate, allocate, and process.

Managing resources for multiple trial distributed processing tasks

A method of determining dimensional changes of features in a mask involves calculating a spacing to be used between adjacent unit cells, correcting a unit cell surrounded by replicas of the same unit cell at the calculated spacing for optical proximity effects, arraying the proximity corrected unit cell at the calculated spacing, and dividing the array of unit cells into templates. Each template frames a portion of the array of unit cells, and locations of the unit cells in each framed template are shifted relative to locations of the unit cells in other framed templates. Critical dimensions for features in the unit cell are determined within each template, and the critical dimensions determined across the template are used to obtain shift variances of each feature. A dimensional change is determined for a feature based on the shift variance for that feature.

Determination of dimensional changes of features across mask pattern simulation fields

A system and method of calibrating optical line shortening measurements, and lithography mask for same. The lithography mask comprises a plurality of gratings, with a calibration marker disposed within each grating. The mask is used to pattern resist on a semiconductor wafer for purposes of measuring and calibrating line shortening. The pattern on the wafer is measured and compared to measurements made of the pattern on the mask. The difference gives the amount of line shortening due to flare, and may be used to calibrate line shortening measurements made using optical measurement tools.

Calibration of optical line shortening measurements

A process () is disclosed to measure predetermined wavelength reflectance spectra of a photo resist coated wafer () at a nominal thickness. After coating, the predetermined wavelength reflectance () is measured and the peak heights and valleys in the vicinity of the predetermined wavelength are tabulated. The relative swing ratio is computed () as the average peak height of the spectra at the exposure wavelength. This relative swing ratio is then compared to similar computations on other processes to determine which provides the best critical dimension (CD) control.

Method for determining relative swing curve amplitude

In photo-lithography, one may assess the effect of flare due to various exposure tools. In an example embodiment, in a photo-lithography process on a photo resist coated substrate, there is a method for determining the effect of flare on line shortening. The method comprises, at a first die position on the substrate and in a first exposure, printing a first mask that includes a flare pattern corresponding to one corner of the first mask, and in a second exposure, printing a second mask that includes another flare pattern corresponding to an opposite corner of the second mask. At a second die position on the substrate, a composite mask pattern based on features of the first mask and the second is printed. The printed patterns are developed and measurements are obtained therefrom. The effect of flare is determined as a function of the measurements.

Measuring the effect of flare on line width

In photo-lithography, one may assess the effect of flare due to various exposure tools. In an example embodiment, in a photo-lithography process on a photo resist coated substrate, there is a method () for determining the effect of flare on line shortening. The method () comprises, at a first die position on the substrate and in a first exposure, printing a first mask () that includes a flare pattern () corresponding to one corner of the first mask (), and in a second exposure, printing a second mask () that includes another flare pattern corresponding to an opposite corner of the second mask. At a second die position on the substrate, a composite mask pattern () based on features of the first mask and the second is printed. The printed patterns () are developed and measurements () are obtained therefrom. The effect of flare () is determined as a function of the measurements.

In the manufacture of semiconductors, it is often necessary to characterize the effect of line width and line width shape on yield. In an example embodiment, there is a method () for randomizing exposure conditions across a substrate. The method comprises generating a list of random numbers (). A random number is mapped () to an exposure field, forming a list of random numbers and corresponding exposure fields. The list or random numbers and corresponding exposure fields is sorted () by random number. To each exposure field in the list sorted by random number, an exposure dose is assigned (). The list is sorted is sorted by exposure field ().

System and method for characterizing lithography effects on a wafer

In an example embodiment, there is a method () for determining an approximately optimal resist thickness comprising providing a first substrate coated with a resist film having a first thickness using a first coat program, (). The first thickness of resist is measured (). A second substrate is provided () and coated with a resist film using the first coat program. The resist film on the second substrate is exposed to radiation. The reflectance spectrum near the actinic wavelength of the resist film is measured (). As a function of the periodicity of the reflectance spectrum, an effective refractive index is determined. Based on the effective refractive index, a periodicity of a swing curve of the resist film coated on the second substrate is determined (). The maxima and minima are determined as a function of the periodicity.

Method for determining optimal resist thickness

A system and method for measuring optical properties of films deposited or formed on semiconductor wafers. Measurements of an optical property are made in a plurality of non-overlapping locations within a test region of a film at a low radiation dose, and the measurements are averaged. The radiation dose is less than the actinic radiation sensitivity dose of the film, so that chemical changes in the film are not caused by the measurements. The measurements may be calibrated to prior art methods, and the results may be adjusted by the adjustment or calibration factor.

Measurement of optical properties of radiation sensitive materials

Systems, methods, and lithography masks for measuring flare in semiconductor lithography. A layer of photosensitive material is exposed to a first test pattern and a second test pattern, the second test pattern comprising an opaque or attenuated region. The second test pattern is placed proximate features formed in a photosensitive material in a first exposure by the first test pattern, in a second exposure by the second test pattern on the same mask or a different mask. Alternatively, the second test pattern may be disposed proximate a portion of the first test pattern on a single mask using a single exposure. If flare exists in the optical system, the second test pattern causes line shortening in the features formed in the photosensitive material of the first test pattern. The line shortening can be measured to determine the effect of flare in the lithography system.

Measuring flare in semiconductor lithography

There is a method for manufacturing wafers. In an example embodiment, the method employs a stepper with a reticle, lens, and stage movement parameters that comprise providing a set of intentionally-misaligned calibration wafers with predetermined input corrections, the input corrections accounting for linearity of response and interactions between the reticle, lens and stage movement parameters of the stepper. The stepper is calibrated by using the predetermined input corrections from the set of intentionally misaligned calibration wafers. Using the calibrated stepper, aligned patterns on the wafers are printed.

Calibration wafer for a stepper

A technique is provided to define a pattern ( ) on a substrate ( ) that includes a dense region with a number of features ( ) and an isolated feature region comprised of at least a part of one of the features ( ). The dense feature region has a greater feature density than the isolated feature region. A reference feature ( ) is measured at a number of different points relative to the isolated feature region and the dense feature region with a measurement tool ( ). An iso-dense effect is determined from these measurements.

Techniques to characterize iso-dense effects for microdevice manufacture

A method for improving substrate alignment on a stepper comprises imposing predetermined corrections on each of a plurality of substrates, a different set of corrections for each substrate. The actual corrections occurring on the substrates are measured and mathematically processed to produce a matrix and a plurality of equations. The equations are resolved to provide correct corrections for accurate alignment.

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San Antonio, TX, United States of America

David Howard Ziger