Abstract:
Methods and systems for reducing illumination intensity while scanning over large particles are presented herein. A surface inspection system determines the presence of a large particle in the inspection path of a primary measurement spot using a separate leading measurement spot. The inspection system reduces the incident illumination power while the large particle is within the primary measurement spot. The primary measurement spot and the leading measurement spot are separately imaged by a common imaging collection objective onto one or more detectors. The imaging based collection design spatially separates the image of the leading measurement spot from the image of the primary measurement spot at one or more wafer image planes. Light detected from the leading measurement spot is analyzed to determine a reduced power time interval when the optical power of the primary illumination beam and the leading illumination beam are reduced.
Abstract:
A beam splitter includes first and second prisms. The first prism includes first, second, and third optical surfaces. The second prism includes three surfaces, one of which faces the second surface of the first prism and both transmit and reflect light. The first surface of the first prism is curved and forms a lens for focusing light either transmitted or reflected by the common interface between the two prisms. The first prism is from a single piece of material. Fabrication includes making two cuts through a lens to cut-out an intermediate section. A portion of the intermediate section is cut-off to form the third surface of the first prism. The first surface of the first prism corresponds to the curved top surface of the lens. The second surface of the first prism corresponds to the bottom plano surface of the lens. The first and second prisms are then combined.
Abstract:
Methods, systems, and structures for monitoring incident beam position in a wafer inspection system are provided. One structure includes a feature formed in a chuck configured to support a wafer during inspection by the wafer inspection system. The chuck rotates the wafer in a theta direction and simultaneously translates the wafer in a radial direction during the inspection. An axis through the center of the feature is aligned with a radius of the chuck such that a position of the axis relative to an incident beam of the wafer inspection system indicates changes in the incident beam position in the theta direction.
Abstract:
The disclosure is directed to a system and method for inspecting a spinning sample by substantially simultaneously scanning multiple spots on a surface of the sample utilizing a plurality of illumination beams. Portions of illumination reflected, scattered, or radiated from respective spots on the surface of the sample are collected by at least one detector array. Information associated with at least one defect of the sample is determined by at least one computing system in communication with the detector array. According to various embodiments, at least one of scan pitch, spot size, spot separation, and spin rate is controlled to compensate pitch error due to tangential spot separation.
Abstract:
Methods and systems for reducing illumination intensity while scanning over large particles are presented herein. A surface inspection system determines the presence of a large particle in the inspection path of a primary measurement spot using a separate leading measurement spot. The inspection system reduces the incident illumination power while the large particle is within the primary measurement spot. The primary measurement spot and the leading measurement spot are separately imaged by a common imaging collection objective onto one or more detectors. The imaging based collection design spatially separates the image of the leading measurement spot from the image of the primary measurement spot at one or more wafer image planes. Light detected from the leading measurement spot is analyzed to determine a reduced power time interval when the optical power of the primary illumination beam and the leading illumination beam are reduced.
Abstract:
The disclosure is directed to a system and method for inspecting a spinning sample by substantially simultaneously scanning multiple spots on a surface of the sample utilizing a plurality of illumination beams. Portions of illumination reflected, scattered, or radiated from respective spots on the surface of the sample are collected by at least one detector array. Information associated with at least one defect of the sample is determined by at least one computing system in communication with the detector array. According to various embodiments, at least one of scan pitch, spot size, spot separation, and spin rate is controlled to compensate pitch error due to tangential spot separation.
Abstract:
A wafer scanning system includes imaging collection optics to reduce the effective spot size. Smaller spot size decreases the number of photons scattered by the surface proportionally to the area of the spot. Air scatter is also reduced. TDI is used to produce a wafer image based on a plurality of image signals integrated over the direction of linear motion of the wafer. An illumination system floods the wafer with light, and the task of creating the spot is allocated to the imaging collection optics.
Abstract:
A method and system for providing illumination is disclosed. The method may include providing a laser having a predetermined wavelength; performing at least one of: beam splitting or beam scanning prior to a frequency conversion; converting a frequency of each output beam of the at least one of: beam splitting or beam scanning; and providing the frequency converted output beam for illumination.
Abstract:
A wafer scanning system includes imaging collection optics to reduce the effective spot size. Smaller spot size decreases the number of photons scattered by the surface proportionally to the area of the spot. Air scatter is also reduced. TDI is used to produce a wafer image based on a plurality of image signals integrated over the direction of linear motion of the wafer. An illumination system floods the wafer with light, and the task of creating the spot is allocated to the imaging collection optics.
Abstract:
Methods, systems, and structures for monitoring incident beam position in a wafer inspection system are provided. One structure includes a feature formed in a chuck configured to support a wafer during inspection by the wafer inspection system. The chuck rotates the wafer in a theta direction and simultaneously translates the wafer in a radial direction during the inspection. An axis through the center of the feature is aligned with a radius of the chuck such that a position of the axis relative to an incident beam of the wafer inspection system indicates changes in the incident beam position in the theta direction.