Hughes Aircraft Company

The Perkin-elmer Corporation

Integrated Process Equipment Corporation

Peter B Mumola

Sherman K Poultney

Carlo F La Fiandra

Paul R Yoder

George J Gardopee

Raul E Casas

Joseph P Prusak

Thomas J McHugh

William M Grossman

An apparatus (2) that performs high resolution thickness metrology on a thin film layer of a wafer (24), includes a filtered white light source that forms a collimated monochromatic light beam (19). The filtered white light source includes a halogen lamp (10), a condensing lens (12), a circular aperture (14), a collimator lens (16), and a narrow band filter wheel (18). The collimated monochromatic light beam (19) is passed through a beamsplitter (60), a second collimator lens (20), a third collimator lens (22), and a lenslet array (38), such that a corresponding array of sample points (39) on the surface of the wafer (24) are irradiated with focused monochromatic light. A reflectance pattern is formed at each sample point (39) due to coherent interactions in the monochromatic light as it is reflected within the wafer structure (24). An image of each reflectance pattern is reflected off the surface of the wafer (24) and is directed onto a detector array (31) of a charge coupled device (CCD) camera (30). Each reflectance pattern image is displayed on the CCD camera detector array (31) and captured by the CCD camera (30). Each captured image is digitized by a digitizing circuit (34) and stored by a computer (36). The computer (36) then compares this measured reflectance data to reference reflectance data already stored so as to determine the thickness of the thin film layer at each sample point (39) on the wafer (24).

Apparatus and method for performing high spatial resolution thin film

A method for controlling the flow of semiconductor wafers within a semiconductor wafer processing facility. This method includes a wafer storage and preparation area (10) and a wafer metrology and etch area (12), both of which are monitored and/or controlled by a master controller (14). The wafer storage and preparation area (10) is typically kept at a class 10 clean room level and is comprised of a wafer storage area (16) and a wafer preparation area (18). The wafer metrology and etch area (12) is typically kept at a class 1000 clean room level and is comprised of an I/O cassette module (22), a wafer pre-aligner (24), a wafer router (26), a wafer metrology instrument (28), and a wafer etching instrument (30). The semiconductor wafers are transported, either manually or automatically, between the wafer storage area (16) and the wafer preparation area (18), as well as between the wafer storage and preparation area (10) and the wafer metrology and etch area (12), within wafer storage cassettes ( 20). The semiconductor wafers are individually transported between the I/O cassette module (22), the wafer pre-aligner (24), the wafer metrology instrument (28), and the wafer etching instrument (30) by the wafer router (26).

Wafer flow architecture for production wafer processing

A method of planarizing a microstructure (16) includes the steps of providing a layer (18) of material over the microstructure (16) such that an overcoating surface (20) is formed, measuring the thickness of the layer (18) across the surface (20) forming a dwell time versus position map and removing material from the layer (18) of material by use of a plasma assisted chemical etching tool in accordance with the dwell time versus position map.

Method of planarizing microstructures

An apparatus for shielding a plurality of wafer registration surfaces 14, 30 and a wafer retention stage 26 from depreciative effects of a chemical etching process includes a pair of etching shields 32, 32' that are positioned along an outside edge of a wafer 10. The wafer 10 is registered to the wafer retention stage 26 by the registration surfaces 14, 30. The wafer retention stage 26, and hence the wafer 10, rotates about an axis 36 through the center of the wafer 10. A chemical etching instrument probe 18 is moved, with respect to the wafer 10, along a fixed wafer diameter 34 while the wafer 10 is rotating. The probe 18 is initially positioned above a first etching shield 32' and is moved, with respect to the wafer 10, across the wafer diameter 34 until it reaches a second etching shield 32. Thus, the probe 18 scans the entire surface of the wafer 10 without extending outside the wafer edge to depreciatively effect the wafer retention materials 14, 26, 30.

Apparatus and method for shielding a workpiece holding mechanism from

An apparatus (10) that measures the thickness of a thin film layer of a wafer (12) is described. The thickness of the thin film layer is measured by irradiating a reference wafer (22) with a beam (21) of broadband radiation. The reference wafer (22) has a layer structure similar to that of the wafer (12) undergoing measurement, whereby the thin film layer of the reference wafer (22) that corresponds to the thin film layer to be measured is varied over a specific range of known thicknesses. Thus, the incident beam (21) of broadband radiation is reflected from the reference wafer (22) having a unique spectral signature that corresponds to one of these known thicknesses. A reflected beam (23, 25, 27) of unique spectral radiation is projected onto the wafer (12) undergoing measurement, where it is reflected to produce a beam (29) of unique spectral radiation having a characteristic that is indicative of the thickness of the thin film layer to be measured. The characteristic of the beam (29) of unique spectral radiation is captured by a charge coupled device camera (34), and a computer (36) correlates this captured characteristic with one of the known thin film layer thicknesses of the reference wafer (22) to provide an output that corresponds to the thickness of the thin film layer whose thickness is desired to be measured.

Apparatus and method for performing thin film layer thickness metrology

A reactor 10 having a vacuum housing 30 which encloses a plurality of plasma chambers 14a, 14b is used to perform local plasma assisted chemical etching on an etchable substrate 12. The chambers 14a, 14b are movable and are sized according to the removal material footprint desired. Radio frequency driven electrodes 20a, 20b and gas diffuser/electrodes 22a, 22b have the same diameter as the chambers 14a, 14b. The substrate 12 is mounted on a substrate holder 44 which also acts as the other electrode. The holder 44 is mounted on an X-Y positioning table 46. A process gas is flowed into a preselected chamber with rf power so as to disassociated the process gas into a plasma. The plasma chambers 14a, 14b may be scanned over the substrate surface while the gap between the chambers and the substrate is varied to yield a desired etch profile.

Method and apparatus for producing variable spatial frequency control in

An apparatus 10 for micropatterning a photoresist coated surface 12 of a semiconductor wafer 14 includes a computer 50 for controlling an image on a screen 29 of a cathode ray tube (CRT) 30. The CRT screen 29 is optically connected to a liquid crystal light valve (LCLV) 26 by a fiber optic faceplate 28. This connection is such that the computer controlled image on the CRT screen 29 is reproduced on the face 27 of the LCLV 26 as a reflective pattern of this image. An argon-ion laser 16 provides a polarized monochromatic light beam 18 that is reflected from the face 27 of the LCLV 26. This reflected beam 32 is convergently focused by a lens system 36 onto a projected area 37 of the photoresist coated wafer surface 12, thereby exposing the photoresist with an image of the LCLV reflective pattern. A helium-neon laser 38 provides a polarized monochromatic light beam 44 that is convergently focused onto the same projected area 37 of the wafer surface 12. However, the wavelength of the helium-neon provided light beam 44 is such that there is no exposure to the photoresist coated wafer surface 12. The helium-neon light beam is reflected from the projected area 37 of the wafer surface 12 and directed toward an image plane 49 of a charge coupled device (CCD) camera 48. The CCD camera 48 captures an image of the projected area 37 of the wafer surface 12 and a computer 50 digitizes this image. The computer 50 determines the position of the wafer 14 with respect to the projected reflective pattern image, and updates the image on the CRT screen 29 if the projected reflective pattern image is not properly aligned onto the wafer surface 12. Thus, the entire surface 12 of the wafer 14 may be micropatterned by moving the wafer 14 and updating the CRT screen 29 image in accordance with this movement.

Exposure device including an electrically aligned electronic mask for

This invention is directed to an actuator which is particularly adapted among many other possible uses, or use in adjusting the configuration of deformable mirrors. The actuator comprises a housing mounted for movement on a fixed base, the housing being fabricated from magnetic material and being configured to have two spaced pole faces of opposite polarity, a housing coil mounted on the housing to form an electro-magnet, apparatus for moving the housing having infinite reflected inertia, a force arm mounted for movement on a fixed base, one portion of the force arm having an output drive pick-off and another portion of the force arm being disposed between the poles faces of the housing, pole pieces mounted on the force arm adjacent the pole faces, respectively, a force arm coil mounted on the force arm to form an electro-magnet, a first permanent magnet mounted on the housing and a second permanent magnet mounted on the force arm which coact to form a magnet coupling between the force arm and the housing, a controller for controlling the apparatus for moving the housing to thereby control the course adjustment output from the force arm and provide low frequency integration of the force arm and for controlling the flow of current to the housing coil and the force arm coil to provide a net force greater than the net force of the two permanent magnets to thereby control the fine adjustment output from the force arm.

Actuator

An encoder for providing a conical array of temporally phased pulse beams. A pulse is inserted and continuously recirculated around an optical ring. The pulse is amplified during each circulation and a portion of the pulse is emitted at the end of each circulation. The encoder includes means for spatially separating each emitted pulse to provide a conical array of beams at a constant field angle relative to the optical axis of propagation.

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Huntington, CT, United States of America

Peter B Mumola