Abstract: Heat is applied to a conductive structure that includes one or more vias, and the temperature at or near the point of heat application is measured. The measured temperature indicates the integrity or the defectiveness of various features (e.g. vias and/or traces) in the conductive structure, near the point of heat application. Specifically, a higher temperature measurement (as compared to a measurement in a reference structure) indicates a reduced heat transfer from the point of heat application, and therefore indicates a defect. The reference structure can be in the same die as the conductive structure (e.g. to provide a baseline) or outside the die but in the same wafer (e.g. in a test structure) or outside the wafer (e.g. in a reference wafer), depending on the embodiment.

Abstract: A sidewall or other feature in a semiconductor wafer is evaluated by illuminating the wafer with at least one beam of electromagnetic radiation, and measuring intensity of a portion of the beam reflected by the wafer. Change in reflectance between measurements provides a measure of a property of the feature. The change may be either a decrease in reflectance or an increase in reflectance, depending on the embodiment. A single beam may be used if it is polarized in a direction substantially perpendicular to a longitudinal direction of the sidewall. A portion of the energy of the beam is absorbed by the sidewall, thereby to cause a decrease in reflectance when compared to reflectance by a flat region. Alternatively, two beams may be used, of which a first beam applies heat to the feature itself or to a region adjacent to the feature, and a second beam is used to measure an increase in reflectance caused by an elevation in temperature due to heat transfer through the feature.

Abstract: A method and apparatus measure properties of two layers of a damascene structure (e.g. a silicon wafer during fabrication), and use the two measurements to identify a location as having voids. The two measurements may be used in any manner, e.g. compared to one another, and voids are deemed to be present when the two measurements diverge from each other. In response to the detection of voids, a process parameter used in fabrication of the damascene structure may be changed, to reduce or eliminate voids in to-be-formed structures.

Abstract: A structure having a number of traces passing through a region is evaluated by using a beam of electromagnetic radiation to illuminate the region, and generating an electrical signal that indicates an attribute of a portion (also called “reflected portion”) of the beam reflected from the region. The just-described acts of “illuminating” and “generating” are repeated in another region, followed by a comparison of the generated signals to identify variation of a property between the two regions. Such measurements can identify variations in material properties (or dimensions) between different regions in a single semiconductor wafer of the type used in fabrication of integrated circuit dice, or even between multiple such wafers. In one embodiment, the traces are each substantially parallel to and adjacent to the other, and the beam has wavelength greater than or equal to a pitch between at least two of the traces.

Abstract: A coefficient of a function that relates a measurement from a wafer to a parameter used in making the measurement (such as the power of a beam used in the measurement) is determined. The coefficient is used to evaluate the wafer (e.g. to accept or reject the wafer for further processing), and/or to control fabrication of another wafer. In one embodiment, the coefficient is used to control operation of a wafer processing unit (that may include, e.g. an ion implanter), or a heat treatment unit (such as a rapid thermal annealer).

Abstract: An apparatus measures a property of a layer (such as the sheet resistance of a conductive layer or thermal conductivity of a dielectric layer that is located underneath the conductive layer) by performing the following method: (1) focusing the heating beam on the heated a region (also called “heated region”) of the conductive layer (2) modulating the power of the heating beam at a predetermined frequency that is selected to be sufficiently low to ensure that at least a majority (preferably all) of the generated heat transfers out of the heated region by diffusion, and (3) measuring the power of another beam that is (a) reflected by the heated region, and (b) modulated in phase with modulation of the heating beam. The measurement in act (3) can be used directly as a measure of the resistance (per unit length) of a conductive line formed by patterning the conductive layer.

Abstract: A method (1) creates charge carriers in a concentration that changes in a periodic manner (also called “modulation”) only with respect to time, and (2) determines the number of charge carriers created in the carrier creation region by measuring an interference signal obtained by interference between a reference beam and a portion of a probe beam that is reflected by charge carriers at various depths of the semiconductor material, and comparing the measurement with corresponding values obtained by simulation (e.g. in graphs of such measurements for different junction depths). Various properties of the reflected portion of the probe beam (such as power and phase) are functions of the depth at which the reflection occurs, and can be measured to determine the depth of the junction, and the profile of active dopants.

Abstract: A method (1) creates charge carriers in a concentration that changes in a periodic manner (also called “modulation”) only with respect to time, and (2) determines the umber of charge carriers created in the carrier creation region by measuring an interference signal obtained by interference between a reference beam and a portion of a probe beam that is reflected by charge carriers at various depths of the semiconductor material, and comparing the measurement with corresponding values obtained by simulation (e.g. in graphs of such measurements for different junction depths). Various properties of the reflected portion of the probe beam (such as power and phase) are functions of the depth at which the reflection occurs, and can be measured to determine the depth of the junction, and the profile of active dopants.

Abstract: A system for measuring an amount of microroughness of a surface of a substrate, wherein a first beam of electromagnetic radiation and a second beam of electromagnetic radiation are generated, the first and second beams being substantially parallel and spaced apart from each other so that the first and second beams are substantially non-overlapping, and the first and second beams are focused onto the substrate so that the beams impinge upon a selected area of the surface of the substrate having a surface contour, the surface contour of the substrate causing a scattering of both beams. The scattering of the first and second beams is detected, the amount of scattering corresponding to a microroughness value of the selected area of the substrate, and the microroughness value of the selected area of the substrate is determined from the amount of scattering of the first and second beams. The microroughness measuring system may also be used for controlling a fabrication process.

Abstract: A system for measuring a property of a semiconductor substrate, wherein an analyzer beam is generated and transmitted to the substrate, and a generation beam, superposed on top of the analyzer beam, is also generated and transmitted to the substrate. A response generated by the generation beam, in the substrate, causes a change in a predetermined characteristic of the analyzer beam that is measured by a detector. The property of the substrate is then determined from the change in a predetermined characteristic. The property measuring system may be used in a semiconductor fabrication process.

Abstract: A system for measuring the doping levels of a doped region in a semiconductor substrate, wherein an analyzer beam and a reference beam are generated, the analyzer and reference beams being substantially parallel and spaced apart from each other so that the analyzer and reference beams are non-overlapping. The analyzer beam is focused on a preselected doped region of the substrate and the reference beam is focused on an undoped region of the substrate, the doped region generating a phase shift of the analyzer beam relative to the reference beam corresponding to a level of doping of the doped region of the substrate. A detector detects the phase shift of the analyzer beam relative to the reference beam, and the doping level of the substrate in the preselected doped region is determined from the phase shift. The doping level measuring system may be used to control a semiconductor fabrication process.

Abstract: A system for measuring an amount of microroughness of a surface of a substrate, wherein a first beam of electromagnetic radiation and a second beam of electromagnetic radiation are generated, the first and second beams being substantially parallel and spaced apart from each other so that the first and second beams are substantially non-overlapping, and the first and second beams are focused onto the substrate so that the beams impinge upon a selected area of the surface of the substrate having a surface contour, the surface contour of the substrate causing a scattering of both beams. The scattering of the first and second beams is detected, the amount of scattering corresponding to a microroughness value of the selected area of the substrate, and the microroughness value of the selected area of the substrate is determined from the amount of scattering of the first and second beams. The microroughness measuring system may also be used for controlling a fabrication process.