Prometrix Corporation

Therma-wave, Inc.

Kla-tencop. Corporation

Hung V Pham

Adam Eales Norton

Chester L Mallory

Clinton Carlisle

Fred E Stanke

Barry G Broome

Edric Tong

Elliot Burke

Michael Weber-Grabau

David S Perloff

James M Cahill

Douglas E Ruth

Paul Rasmussen

Phillip D Wasserman

Sandor Droblisch

This invention is an apparatus for imaging metrology, which in particular embodiments may be integrated with a processor station such that a metrology station is apart from but coupled to a process station. The metrology station is provided with a first imaging camera with a first field of view containing the measurement region. Alternate embodiments include a second imaging camera with a second field of view. Preferred embodiments comprise a broadband ultraviolet light source, although other embodiments may have a visible or near infrared light source of broad or narrow optical bandwidth. Embodiments including a broad bandwidth source typically include a spectrograph, or an imaging spectrograph. Particular embodiments may include curved, reflective optics or a measurement region wetted by a liquid. In a typical embodiment, the metrology station and the measurement region are configured to have 4 degrees of freedom of movement relative to each other.

Wafer metrology apparatus and method

An improved method and apparatus for measuring the relative reflectance spectra of an observed sample (3) and method and apparatus for autofocussing the sample (3). A broadband visible and ultraviolet beam (42) is split into a sample beam (46) and a reference beam (48). The sample beam (46) is reflected off the surface of the sample (3), and the spectrum of the reflected sample beam (46) is compared to the spectrum of the reference beam (48) to determine the relative reflectance spectrum of the sample (3). A video camera (96) is provided for viewing the sample (3). The autofocus system has a course-focus mode and a fine-focus mode. In the course-focus mode, the sample (3) is focused when the centroid of the sample image is centered on a position sensitive detector (99). In the fine-focus mode, the sample is focused when the intensity of light reaching the detector (99) is minimized.

Broadband microspectro-reflectometer

A method and system for performing reflectance measurements of a sample using radiation having UV frequency components (preferably in a broad UV band) and visible frequency components (preferably in a broad band). Preferably, two detectors simultaneously receive a sample beam reflected from the sample surface. One detector generates a signal indicative of the sample beam components in the UV band and the other detector generates a signal indicative of the sample beam components in the visible band. By processing these two signals, the invention enables accurate measurement of the thickness of a very thin film on the sample. Preferably, the system determines a single effective wavelength for the UV radiation incident on the first detector and a single effective wavelength for the visible radiation incident on the second detector. Embodiments of the system can also measure reflectance spectra and refractive indices, and can determine lithographic exposure times. Preferred embodiments include an objective lens assembly having a pupil stop with an entrance portion with one or more relatively large apertures therethrough and an exit portion with one or more relatively small apertures therethrough. Illuminating radiation passes through the relatively large apertures before reflecting from the sample, and then passes through the relatively small apertures after reflecting from the sample. This design and pupil stop orientation dramatically increases the insensitivity of the system to ripple on the sample surface.

Method and apparatus for measuring reflectance in two wavelength bands

An autofocusing system for a microscope is disclosed. An autofocus target is placed between a colliminating lens and a relay lens of the microscope. The autofocus target contains a pattern of dark areas which are projected onto a specimen and reflected into a CCD camera array. The focus of the microscope is adjusted such that the variation in intensity of light through the pattern is maximized.

Autofocusing system for microscope having contrast detection means

An automatic system for performing sheet resistivity testing on surface layers of semiconductor wafers, including a wafer handling stage having a platform for carrying a semiconductor wafer, and an arrangement for mounting the platform for rotation about a central axis and for translation of the platform orthogonal to a major surface thereof. A platform drive translates the platform between a wafer test position and a wafer load position, and a stage drive rotates the platform to accurately located angular test positions. A probe handling arrangement includes a carriage for carrying a test probe parallel to the major surface of a wafer on the platform and a carriage drive translates the carriage between a parked position in which a test prove thereon is positioned adjacent and clear of the platform and accurately located test positions along a radius of the platform. The carriage carries a resistivity test probe which includes test probe element for contacting the surface of a semiconductor wafer. A light tight housing surrounds the platform and includes an access door therein facing the platform and positioned intermediate the wafer load position and the wafer test position of the platform. The access door translates under controlled motor drive between a closed position and an open position which permits the platform to translate between the wafer load and wafer test positions. Sensor arrangements cooperate with a safety inhibit circuit to preclude destructive movement of components when position conflict is sensed. All movements and measurements are under microcomputer control.

Apparatus and methods for semiconductor wafer testing

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San Jose, CA, United States of America

Hung V Pham