Abstract: A laser-beam power-modulation system includes an acousto-optic modulator (AOM) to receive a laser beam and separate the laser beam into a primary beam and a plurality of diffracted beams based on an input signal. The power of the primary beam depends on the input signal. The system also includes a slit to transmit the primary beam and dump the plurality of diffracted beams, a controller to generate a control signal based at least in part on feedback indicative of the power of the primary beam or the power of a beam generated using the primary beam, and a driver to generate the input signal based at least in part on the control signal.

Abstract: Systems, methods, and apparatuses are disclosed herein for directing, using an optical arrangement including one or more lenses, a main beam and a leading beam toward a specimen such that the main beam is incident on the specimen at a main beam incidence and the leading beam is incident on the specimen at a leading beam incidence. The main beam intensity is greater than a leading beam intensity of the leading beam. A TDI sensor receives electromagnetic radiation from the leading beam incidence, thereby generating a first accumulated charge portion, and receives electromagnetic radiation from the main beam incidence, thereby generating a second accumulated charge portion. A processor maps the first accumulated charge portion to a first FOV, thereby yielding leading beam data, and maps the second accumulated charge portion to a second FOV, thereby yielding main beam data.

Abstract: A laser-beam power-modulation system includes an acousto-optic modulator (AOM) to receive a laser beam and separate the laser beam into a primary beam and a plurality of diffracted beams based on an input signal. The power of the primary beam depends on the input signal. The system also includes a slit to transmit the primary beam and dump the plurality of diffracted beams, a controller to generate a control signal based at least in part on feedback indicative of the power of the primary beam or the power of a beam generated using the primary beam, and a driver to generate the input signal based at least in part on the control signal.

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: 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 calibration wafer and a method for calibrating an interferometer system are disclosed. The calibration method includes: determining locations of the holes defined in the calibration wafer based on two opposite intensity frame; comparing the locations of the holes against the locations measured utilizing an external measurement device; adjusting a first optical magnification or a second optical magnification at least partially based on the comparison result; defining a first distortion map for each of the first and second intensity frames based on the comparison of the locations of the holes; generating an extended distortion map for each of the first and second intensity frames by map fitting the first distortion map; and utilizing the extended distortion map for each of the first and second intensity frames to reduce at least one of: a registration error or an optical distortion in a subsequent measurement process.

Abstract: Systems and methods for inspecting an edge of a specimen are provided. One system includes an illumination subsystem configured to direct light to the edge of the specimen at an oblique angle of incidence. The plane of incidence of the light is substantially perpendicular to a plane substantially tangent to the edge of the specimen. The system also includes a detection subsystem configured to collect light scattered from the edge and to generate signals responsive to the scattered light. One method includes directing light to the edge of the specimen at an oblique angle of incidence. The plane of incidence is substantially perpendicular to a plane substantially tangent to the edge of the specimen. The method also includes collecting light scattered from the edge and generating signals responsive to the scattered light. The signals described above can be used to detect defects on the edge of the specimen.

Abstract: Non-contact methods for determining a parameter of an insulating film are provided. One method includes measuring at least two surface voltages of the insulating film. The surface voltages are measured after different charge depositions. Measuring the surface voltages is performed in two or more sequences. The method also includes determining individual parameters for the two or more sequences from the surface voltages and the charge depositions. In addition, the method includes determining the parameter of the insulating film as an average of the individual parameters. The parameter is substantially independent of leakage in the insulating film. Another method includes determining a characteristic of nitrogen in an insulating film using two parameters of the insulating film selected from equivalent oxide thickness, optical thickness, and a measure of leakage through the insulating film. The characteristic may be a nitrogen dose, a nitrogen percentage, or a presence of nitrogen in the insulating film.