摘要:
Before the diffraction from a diffracting structure on a semiconductor wafer is measured, where necessary, the film thickness and index of refraction of the films underneath the structure are first measured using spectroscopic reflectometry or spectroscopic ellipsometry. A rigorous model is then used to calculate intensity or ellipsometric signatures of the diffracting structure. The diffracting structure is then measured using a spectroscopic scatterometer using polarized and broadband radiation to obtain an intensity or ellipsometric signature of the diffracting structure. Such signature is then matched with the signatures in the database to determine the grating shape parameters of the structure.
摘要:
Before the diffraction from a diffracting structure on a semiconductor wafer is measured, where necessary, the film thickness and index of refraction of the films underneath the structure are first measured using spectroscopic reflectometry or spectroscopic ellipsometry. A rigorous model is then used to calculate intensity or ellipsometric signatures of the diffracting structure. The diffracting structure is then measured using a spectroscopic scatterometer using polarized and broadband radiation to obtain an intensity or ellipsometric signature of the diffracting structure. Such signature is then matched with the signatures in the database to determine the grating shape parameters of the structure.
摘要:
Before the diffraction from a diffracting structure on a semiconductor wafer is measured, where necessary, the film thickness and index of refraction of the films underneath the structure are first measured using spectroscopic reflectometry or spectroscopic ellipsometry. A rigorous model is then used to calculate intensity or ellipsometric signatures of the diffracting structure. The diffracting structure is then measured using a spectroscopic scatterometer using polarized and broadband radiation to obtain an intensity or ellipsometric signature of the diffracting structure. Such signature is then matched with the signatures in the database to determine the grating shape parameters of the structure.
摘要:
Before the diffraction from a diffracting structure on a semiconductor wafer is measured, where necessary, the film thickness and index of refraction of the films underneath the structure are first measured using spectroscopic reflectometry or spectroscopic ellipsometry. A rigorous model is then used to calculate intensity or ellipsometric signatures of the diffracting structure. The diffracting structure is then measured using a spectroscopic scatterometer using polarized and broadband radiation to obtain an intensity or ellipsometric signature of the diffracting structure. Such signature is then matched with the signatures in the database to determine the grating shape parameters of the structure.
摘要:
Increased impact resistance capability is achieved in a cost and weight efficient manner by providing a spinner made of a 3-D orthogonal woven composite material. The spinner defines a generally conical shell having a plurality of axial rib stiffeners and at least one circumferential rib stiffener integrally formed thereon. The combination of the integral rib stiffeners with the 3-D orthogonal woven composite material results in a substantially greater torsional stiffness. The use of the 3-D orthogonal woven composite material also eliminates delamination found in laminated composite spinners.
摘要:
Before the diffraction from a diffracting structure on a semiconductor wafer is measured, where necessary, the film thickness and index of refraction of the films underneath the structure are first measured using spectroscopic reflectometry or spectroscopic ellipsometry. A rigorous model is then used to calculate intensity or ellipsometric signatures of the diffracting structure. The diffracting structure is then measured using a spectroscopic scatterometer using polarized and broadband radiation to obtain an intensity or ellipsometric signature of the diffracting structure. Such signature is then matched with the signatures in the database to determine the grating shape parameters of the structure.
摘要:
Before the diffraction from a diffracting structure on a semiconductor wafer is measured, where necessary, the film thickness and index of refraction of the films underneath the structure are first measured using spectroscopic reflectometry or spectroscopic ellipsometry. A rigorous model is then used to calculate intensity or ellipsometric signatures of the diffracting structure. The diffracting structure is then measured using a spectroscopic scatterometer using polarized and broadband radiation to obtain an intensity or ellipsometric signature of the diffracting structure. Such signature is then matched with the signatures in the database to determine the grating shape parameters of the structure.
摘要:
Before the diffraction from a diffracting structure on a semiconductor wafer is measured, where necessary, the film thickness and index of refraction of the films underneath the structure are first measured using spectroscopic reflectometry or spectroscopic ellipsometry. A rigorous model is then used to calculate intensity or ellipsometric signatures of the diffracting structure. The diffracting structure is then measured using a spectroscopic scatterometer using polarized and broadband radiation to obtain an intensity or ellipsometric signature of the diffracting structure. Such signature is then matched with the signatures in the database to determine the grating shape parameters of the structure.
摘要:
The film thickness and surface profile of a test sample consisting of optically dissimilar regions are measured by phase-shifting interferometry. Conventional phase-shifting interferometry at a given wavelength is performed to measure the step height between two regions of the surface. The theoretical measured step height as a function of the film thickness is then calculated. A set of possible solutions corresponding to the experimentally measured-height are found numerically or graphically by searching the theoretically generated function at the measured height. If more than one solution exists, the phase-shifting procedure is repeated at a different wavelength and a new theoretical measured-height as a function of the film thickness is calculated for the optical parameters of the materials at the new wavelength, yielding another set of possible solutions that correspond to the newly measured height. The number of repetitions of the procedure depends on the number of unknowns of the test sample. The film thicknesses are obtained by comparing all possible solution sets and finding the single combination of thicknesses corresponding to the experimentally measured heights at different measurement wavelengths. The same method may also be used for reconstructing a 3-dimensional profile of the patterned film surface by measuring the film thickness variation point by point across the entire measurement field.
摘要:
A method and system are described for performing phase unwrapping integrations in a phase-shifting interferometric profiling operation. The disclosed technique uses one characteristic of modulation or slope distributions to segment the modulation or slope histogram into a plurality of sections. The principal phase values are divided into a plurality of groups in accordance with corresponding modulation or slope histogram sections. The phase unwrapping integrations are performed in such an order that the areas with a high probability of containing a 2.pi. discontinuity are contained in the last group integrated. Thus, inaccuracies due to 2.pi. discontinuities do not "propagate" to earlier-computed phase values computed by the phase unwrapping algorithm.