Zygo Corporation

Other

Kla Instruments Corporation

Mark Davidson

Peter J De Groot

Leslie Ludwig Deck

Xavier Colonna De Lega

Jan Liesener

Mario Rabinowitz

Isaac Mazor

Kalman Kaufman

A system includes an interference microscope having one or more optical elements arranged to image a test object to an image plane by combining test light from the test object with reference light from a reference object to form an interference pattern at the image plane, wherein the test and reference light are derived from a common broadband light source. The system includes a scanning stage configured to scan an optical path difference (OPD) between the test and reference light, a multi-element detector positioned at the image plane and configured to record the interference pattern for each of a series of OPD increments and to generate multiple interferometry signals each having a fringe carrier frequency indicative of changes in the OPD as the OPD is scanned, where there is phase diversity among the interferometry signals, and an electronic processor coupled to the multi-element detector and scanning stage and configured to process the interference signals based on the phase diversity to determine information about the OPD increments having sensitivity to perturbations to the OPD increments at frequencies greater than the fringe carrier frequency.

Low coherence interferometry with scan error correction

Apparatus include a microscope including an objective and a stage for positioning a test object relative to the objective, the stage being moveable with respect to the objective, and a sensor system, that includes a sensor light source, an interferometric sensor configured to receive light from the sensor light source, to introduce an optical path difference (OPD) between a first portion and a second portion of the light, the OPD being related to a distance between the objective lens and the stage, and to combine the first and second portions of the light to provide output light, a detector configured to detect the output light from the interferometric sensor, a fiber waveguide configured to direct light between the sensor light source, the interferometric sensor and the detector, a tunable optical cavity in a path of the light from the sensor light source and the interferometric sensor, and an electronic controller in communication with the detector, the electronic controller being configured to determine information related to the OPD based on the detected output light.

Fiber-based interferometer system for monitoring an imaging interferometer

In certain aspects, interferometry methods are disclosed that include providing one or more interferometry signals for a test object, wherein the interferometry signals correspond to a sequence of optical path difference (OPD) values which are not all equally spaced from one another because of noise, providing information about the unequal spacing of the sequence of OPD values, decomposing each of the interferometry signals into a contribution from a plurality of basis functions each corresponding to a different frequency and sampled at the unequally spaced OPD values, and using information about the contribution from each of the multiple basis functions to each of the interferometry signals to determine information about the test object.

Interferometric systems and methods featuring spectral analysis of unevenly sampled data

An apparatus includes an interferometer configured to generate an interference pattern by combining test light from a test object with reference light reflected from a reference object, the interferometer being further configured to direct at least a first part of a monitor test beam to the test object at a first incident angle and at least a second part of a monitor reference beam to the reference object at a second incident angle, and recombine the first part and the second part of the monitor beams after they reflect from the test and reference surfaces to interfere with one another and form a monitor pattern, where the first and second angles cause the monitor pattern to have spatial interference fringes, and wherein a change in the position of the interference fringes is indicative of a change in a relative position between the test and reference objects.

Interference microscope with scan motion detection using fringe motion in monitor patterns

In general, in one aspect, the invention features apparatus that includes a broadband scanning interferometry system including interferometer optics for combining test light from a test object with reference light from a reference object to form an interference pattern on a detector, wherein the test and reference light are derived from a common light source. The interferometry system further includes a scanning stage configured to scan an optical path difference (OPD) between the test and reference light from the common source to the detector and a detector system including the detector for recording the interference pattern for each of a series of OPD increments, wherein the frequency of each OPD increment defines a frame rate. The interferometer optics are configured to produce at least two monitor interferometry signals each indicative of changes in the OPD as the OPD is scanned, wherein the detector system is further configured to record the monitor interferometry signals. The apparatus also includes an electronic processor electronically coupled to the detection system and scanning stage and configured to determine information about the OPD increments with sensitivity to perturbations to the OPD increments at frequencies greater than the frame rate.

Scan error correction in low coherence scanning interferometry

Interferometry system are disclosed that include a detector sub-system including a monitor detector, interferometer optics for combining test light from a test object with primary reference light from a first reference interface and secondary reference light from a second reference interface to form a monitor interference pattern on a monitor detector, wherein the first and second reference interfaces are mechanically fixed with respect to each other and the test light, a scanning stage configured to scan an optical path difference (OPD) between the test light and the primary and secondary reference light to the monitor detector while the detector sub-system records the monitor interference pattern for each of a series of OPD increments, and an electronic processor electronically coupled to the detector sub-system and the scanning stage, the electronic processor being configured to determine information about the OPD increments based on the detected monitor interference pattern.

Compound reference interferometer

This invention deals with novel method and apparatus for positioning and motion control by rapid-response motorless linear motion, angular deflection, and continuous rotational motion utilizing the force due to electrons, ions, and/or neutrals. Thus forces and torques are produced without the use of internal moving parts. Control is achieved without recourse to magnetic fields, by means of high electric fields which may be attained at relatively low voltages. At low voltages, the instant invention exceeds the capability of conventional systems. It can perform dynamic motion control over a wide range of dimensions and signal bandwidth with independent amplitude and frequency modulation. Since there are no internal moving parts, the instant invention is the most adapted for fabrication at the micro and nanotechnology realms. Furthermore it provides less costly and greater ease of manufacture from the nano-to the macro-realm.

Positioning and motion control by electrons, ions, and neutrals in electric fields

This invention deals with the broad general concept for focussing light. A mini-optics tracking and focusing system is presented for solar power conversion that ranges from an individual's portable system to solar conversion of electrical power that can be used in large scale power plants for environmentally clean energy. It can be rolled up, transported, and attached to existing man-made, or natural structures. It allows the solar energy conversion system to be low in capital cost and inexpensive to install as it can be attached to existing structures since it does not require the construction of a superstructure of its own. This novel system is uniquely distinct and different from other solar tracking and focusing processes allowing it to be more economical and practical. Furthermore, in its capacity as a power producer, it can be utilized with far greater safety, simplicity, economy, and efficiency in the conversion of solar energy.

Mini-optics solar energy concentrator

This invention deals with a novel general concept for a multi-wavelength switching ensemble which is controlled electrically, electromagetically, or magnetically. A switching system is presented that permits the input to control the output. It allows a full 180 degree rotation of the beam which greatly exceeds the rotational capability of conventional systems. Furthermore, the instant invention permits less costly and greater ease of manufacture.

Dynamic multi-wavelength switching ensemble

This invention deals with the broad general concept for focussing light. A mini-optics tracking and focussing system is presented for solar power conversion that ranges from an individual's portable system to solar conversion of electrical power that can be used in large scale power plants for environmentally clean energy. It can be rolled up, transported, and attached to existing man-made, or natural structures. It allows the solar energy conversion system to be low in capital cost and inexpensive to install as it can be attached to existing structures since it does not require the construction of a superstructure of its own. This novel system is uniquely distinct and different from other solar tracking and focussing processes allowing it to be more economical and practical. Furthermore, in its capacity as a power producer, it can be utilized with far greater safety, simplicity, economy, and efficiency in the conversion of solar energy.

An aplanatic microlens consisting of a sphere which is less than one millimeters in diameter. The sphere is made of a transparent material and has a plane surface ground into it so that the radial distance from the center of the sphere to the nearest point on the plane surface is equal to the radius of the sphere divided by the ratio of the index of refraction of the transparent material and the index of refraction of the medium which will surround the lens in use.

Aplanatic microlens and method for making same

A method whereby the image produced in a coherence probe microscope is modified by means of a certain specific additive electronic transformation for the purpose of improving the measurement of selected features. The technique improves measurement accuracy on optically complex materials, in particular it improves the accuracy of linewidth measurement on semiconductor linewidths.

Method of image enhancement for the coherence probe microscope with

A specially adapted Linnik microscope is used in combination with a video camera, a wafer transport stage and data processing electronics to form a novel inspection apparatus based on the use of the two beam interference microscope. The apparatus can utilize either broad band or narrow band light to develop a plurality of interference images taken at different axial positions relative to the surface under investigation. The point-by-point brightness along scan lines across such images is then used to develop data which is proportional to the degree of coherence (or to the fringe amplitude, the variance of the fringes, or the amplitude of oscillation of the fringes) as the optical path difference is varied in a two beam optical or acoustic microscope.

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Palo Alto, CA, United States of America

Mark Davidson