Abstract: An optically-based system and method are disclosed for detecting surface pits and their average depth in a metal film by an examination of pulse shape in a reflected probe beam pulse. Also disclosed is an optically-based system and method for detecting an occurrence of a failure in a CMP process by detecting surface pits in a metal film by an examination of pulse shape in a reflected probe beam pulse. Also disclosed is an optically-based system and method for providing quality indications to a CMP process for enabling control of the CMP process by detecting surface pits in a metal film by an examination of pulse shape in a reflected probe beam pulse, where the pulse shape has a twin peak shape that is indicative of a presence of a surface pit.

Abstract: A method for calculating the refractive index and the extinction coefficient for materials relates the physical parameters being calculated to the scattering caused by interband states in the material using a model which includes a quantum mechanical transition equation for transitions between valence and/or conduction bands and interband states of the material. The method can be used for material engineering, process control for processes affecting the interband states in the material, and in estimation of the amount of interband states which have been introduced into a material as a result of such a process. Apparatus for implementing the method are also disclosed.

Abstract: An automated metrology system for photoacoustic measurement of single or multi-layer films, and a method of making the system, are disclosed. Dramatic improvements in the cost of ownership of the system is attained by making the system scalable from a system having a single metrology sub-system for making measurements, to a system having two, vertically stacked metrology sub-systems for making independent measurements. A front end of the system for storing multiple cassettes comprises a robot having vertical travel capable of transferring cassettes to and from each of the first and second metrology sub-systems in the case the system is expanded. The two metrology sub-systems are preferably identical and share much of the optics, a computer as well as the front end of the system. Throughput of the dual system is 1.75-2 times greater than that of a single tool metrology system while the cost is substantially less than two complete single tool metrology systems.

Abstract: A system and method for detecting defects in surface structures, such as those formed on semiconductor wafers. A light source, preferably a strobe light, provides illumination that is separated by a filter into a plurality of selected bandwidths. The light then is transported through a fiber optic cable to a diffuser, and from there directed toward the surface. A camera captures a plurality of images, each image formed by a separate portion of the electromagnetic spectrum. The images may be formed by either reflected or diffracted light, or both. The images may be stored or compared to an image of a calibration wafer.

Abstract: A method of collating and using captured semiconductor-wafer image data in an automated defect analysis. The method includes the steps of receiving image data and, if necessary, converting it to a digital format. Once the data is in pixel-by-pixel form, each pixel is assigned a slope value derived from the direction of the structure edge, if any, on which it lies. The pixel-slope data is then evaluated to determine whether a photo-resist anomaly is present. The method may also include evaluated an average pixel slope value for each inspected wafer. Dependant claims further define the invention to claim an inspection system for employing the method.

Abstract: A metrology system has one or more central ‘metrology servers’ and one or more ‘metrology slaves’ The server delivers metrology ‘pump/probe’ signals to multiple slave systems allowing a reduction in the number of high-cost metrology components in the master system. In certain cases, multiple metrology components in the ‘master’ system may provide redundancy while still maintaining a beneficial cost benefit. Reliability can also be improved by using multiple lasers and multiple delay paths with a cross-point switch between them. If one sub-system goes down, the system may ‘serialize’ metrology operations and thereby maintain all systems running, although at somewhat of a reduced throughput. An important element of this invention is grouping all or most of the costly components in a centralized laser server, and issuing pump-probe pulse pairs to remote metrology heads through a light pipe or other conveyance, such as optical fiber.

Abstract: A thickness metrology apparatus and method for accurately determining the actual thickness of thin dielectric film on a semiconductor wafer. The wafer is subjected to a heat treatment such as baking at a heating station of the apparatus to cause desorption of organic compounds from the film. The treated wafer is transferred to a measurement stage where the thickness of the film is measured by an ellipsometer, for example. The actual thickness of the film is determined from the measured thickness and a change in the measured film thickness as a function of time for the film due to absorption of organic compounds onto the film following desorption of organic compounds therefrom.

Abstract: Disclosed are methods and apparatus for reducing thermal loading of a film disposed on a surface of a sample, such as a semiconductor wafer, while obtaining a measurement of a thickness of the film in an area about a measurement site. The method includes steps of (a) bringing an optical assembly of the measurement system into focus; (b) aligning a beam spot with the measurement site; (c) turning on one of a dither EOM or a dither AOM or a piezo-electric dither assembly to sweep the beam spot in an area about the measurement site, thereby reducing the thermal loading within the measurement site; (d) making a measurement by obtaining a signal representing an average for the film under the area; (e) recording the measurement data; and (f) analyzing the measurement data to determine an average film thickness in the measurement area.

Abstract: An optically-based system and method are disclosed for detecting surface pits and their average depth in a metal film by an examination of pulse shape in a reflected probe beam pulse. Also disclosed is an optically-based system and method for detecting an occurrence of a failure in a CMP process by detecting surface pits in a metal film by an examination of pulse shape in a reflected probe beam pulse. Also disclosed is an optically-based system and method for providing quality indications to a CMP process for enabling control of the CMP process by detecting surface pits in a metal film by an examination of pulse shape in a reflected probe beam pulse, where the pulse shape has a twin peak shape that is indicative of a presence of a surface pit. Control of the CMP process includes controlling at least one of polish pressure, speed, polish pad life and polish slurry composition and chemistry.

Abstract: Disclosed are methods and apparatus for reducing thermal loading of a film disposed on a surface of a sample, such as a semiconductor wafer, while obtaining a measurement of a thickness of the film in an area about a measurement site. The method includes steps of (a) bringing an optical assembly of the measurement system into focus; (b) aligning a beam spot with the measurement site; (c) turning on one of a dither EOM or a dither AOM or a piezo-electric dither assembly to sweep the beam spot in an area about the measurement site, thereby reducing the thermal loading within the measurement site; (d) making a measurement by obtaining a signal representing an average for the film under the area; (e) recording the measurement data; and (f) analyzing the measurement data to determine an average film thickness in the measurement area.

Abstract: A metrology system has one or more central ‘metrology servers’ and one or more ‘metrology slaves’ The server delivers metrology ‘pump/probe’ signals to multiple slave systems allowing a reduction in the number of high-cost metrology components in the master system. In certain cases, multiple metrology components in the ‘master’ system may provide redundancy while still maintaining a beneficial cost benefit. Reliability can also be improved by using multiple lasers and multiple delay paths with a cross-point switch between them. If one sub-system goes down, the system may ‘serialize’ metrology operations and thereby maintain all systems running, although at somewhat of a reduced throughput. An important element of this invention is grouping all or most of the costly components in a centralized laser server, and issuing pump-probe pulse pairs to remote metrology heads through a light pipe or other conveyance, such as optical fiber.

Abstract: An improved ellipsometry method and a self-correcting simultaneous multiple angle/multiple wavelength return path ellipsometer are disclosed which allow for simultaneous measurement at multiple angles of incidence in a manner which permits separation of instrument error from the measured properties. In the method polarized light from a single beam of light is simultaneously directed to interact with an optical system under study at different angles of incidence and the change of polarization state is measured for at least one and preferably each of a plurality of the angles of incidence. Non-sample optical system ellipsometric effects of the ellipsometer are measured and the measured changes in polarization state are corrected to eliminate errors introduced thereby. The disclosed embodiment is self-correcting by way of a convex reflector which can be inserted into and removed from the optical path of the beam of polarized light between a focusing optic and the sample optical system under study.