摘要:
An NMR pulse sequence for use in a borehole logging tool includes a series of CPMG pulses according to:T.sub.r -90.degree..sub..+-.x -(t.sub.cp -180.degree..sub.y -t.sub.cp -echo.sub.j)where j is the index of CPMG echoes gathered, T.sub.r is wait time, t.sub.cp is the Carr-Purcell spacing. This pulse sequence is used to determine Bound Fluid Volume (BFV) which is subtracted from total porosity to yield Unbound Fluid Volume (UFV) of a formation surrounding the borehole. Measuring the BVF, the amount of rapidly relaxing fluid (less than 50 ms), is more efficient than measuring UFV (up to 2 secs), and is insensitive to motion of the logging tool.
摘要:
Disclosed is a method, apparatus, and program product for routing an electronic design using sidewall image transfer that is correct by construction. The layout is routed by construction to allow successful manufacturing with sidewall image transfer, since the router will not allow a routing configuration in the layout that cannot be successfully manufactured with a two-mask sidewall image transfer. A layout is produced that can be manufactured by a two-mask sidewall image transfer method. In one approach, interconnections can be in arbitrary directions. In another approach, interconnections follow grid lines in x and y-directions.
摘要:
An apparatus and method for modifying a mask data set includes calculating a derivative of a figure-of-merit, indicative of a data set defined by a plurality of polygon edges and then segmenting polygon edges in response to said step of calculating.
摘要:
An apparatus and method for improving image quality in a photolithographic process includes calculating a figure-of-demerit for a photolithographic mask function and then adjusting said photolithographic mask function to reduce the figure of demerit.
摘要:
A method of measuring flare in an optical lithographic system utilizes an exposure mask with first and second discrete opaque features each having rotational symmetry of order greater than four and of different respective areas. The exposure mask is positioned in the lithographic system such that actinic radiation emitted by the lithographic system illuminates the sensitive surface of an exposure target through the exposure mask. The extent to which regions of the sensitive surface that are within the geometric image of a feature of the exposure mask are exposed to actinic radiation during due to flare is measured.
摘要:
Computational models of a patterning process are described. Any one of these computational models can be implemented as computer-readable program code embodied in computer-readable media. The embodiments described herein explain techniques that can be used to adjust parameters of these models according to measurements, as well as how predictions made from these models can be used to correct lithography data. Corrected lithography data can be used to manufacture a device, such as an integrated circuit.
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 measuring overlay in semiconductor wafers includes a calibration phase in which a series of calibration samples are analyzed. Each calibration sample has an overlay that is known to be less than a predetermined limit. A difference spectrum for a pair of reflectively symmetric overlay targets is obtained for each calibration sample. The difference spectra are then combined to define a gross overlay indicator. In subsequent measurements of actual wafers, difference spectra are compared to the overlay indicator to detect cases of gross overlay.
摘要:
An apparatus and method of compensating for lens imperfections in a projection lithography tool, includes extracting from a diffraction image created by the projection lithography tool a lens transmittance function, and then using the extracted lens transmittance function as a compensator in the lithography projection tool. Another preferred apparatus and method of synthesizing a photomask pattern includes obtaining a phase and an amplitude of a transmittance function of an imaging system; forming a computational model of patterning that includes the transmittance function of the imaging system; and then synthesizing a mask pattern from a given target pattern, by minimizing differences between the target pattern and another pattern that the computational model predicts the synthesized mask pattern will form on a wafer.
摘要:
A calibration method suitable for highly precise and highly accurate surface metrology measurements is described. In preferred embodiments, an optical inspection tool including a movable optics system is characterized in terms of position and wavelength dependent quantities over a range of motion. Once the position-dependant quantities are determined at various wavelengths and positions, they are stored and used to interpret data from test wafers having an unknown metrology. Free of position-dependent variations and other information pertaining to the measurement system, the accuracy of the resulting wafer measurement more closely matches the precision of the tool than existing techniques. In particular embodiments, a portion of the characterization of the optical system is accomplished by using tilted black glass to provide a non-reflective reference.