Abstract: The invention provides calibrated spectrometers in a multi-spectrometer system, where chemical mechanical polishing endpoint detection is an issue. In one aspect of the invention, a spectrometer is calibrated by selecting a filter slide having a predetermined light transmittance or reflectance variation with location (e.g. angular or linear displacement) on the slide. Light is incident on locations on the filter slide, and this incident light is either transmitted or reflected. Transmitted or reflected light is received by a spectrometer, and the wavelength measured is compared with the known wavelength that corresponds to its location on the slide. The spectrometer is calibrated by normalizing the wavelength readings obtained at various locations on the slide with the known readings dictated by the reference slide. The spectrometers are also calibrated to a standard light source for intensity of light.

Abstract: A multi-zoned carrier for a chemical-mechanical planarization (CMP) polishing device includes a center cell, a middle cell, and an outer cell. Each of the cells are in fluid communication with each other through multiple conduits equipped with flow restrictors. The combination of cells and conduits allows more uniformity and planarity to be achieved during the chemical-mechanical planarization (CMP) polishing process.

Abstract: A method and apparatus for cleaning a wafer in a dual brush cleaning system is disclosed. Two brushes, preferably made of PVA and wetted by cleaning fluids, are positioned opposite one another and spaced apart enough to allow a portion of a wafer to be inserted between their working surfaces and make frictional engagement with them. The top brush is rotated at a first speed and the bottom brush is rotated at a second faster speed sufficient for the freely rotating wafer to rotate at the same speed and in the same direction as the top brush. The bottom brush may have raised areas on its surface to assist in efficiently gripping and rotating the wafer. A common rotation speed and direction causes a uniform relative velocity between the top brush and the wafer that results in an improved cleaning operation.

Abstract: A process for quantifying the results of a planarization process provides metrics that can be applied to process parameters that affect the planarization results at various localized regions on a surface being planarized. A surface of a work piece is planarized and the results are recorded as an experimental work piece scan by a plurality of measurements of the amount of material removed as a function of the location on the surface of the work piece. The data from the plurality of measurements are fitted to an mth order polynomial to construct an approximation of a low spatial frequency scan. The work piece surface is then divided into a plurality of regions, each of the regions influenced by a process variable in the planarization process. The approximation of the low spatial frequency scan is then analyzed in each of the regions by fitting the low spatial frequency scan in that region to an nth order polynomial. The coefficient of the nth order term is used as a metric for the results in that region.

Abstract: A method and apparatus for improving uniformity of the rate of removal of material from the surface of a semiconductor substrate by chemical mechanical polishing. In accordance with the invention, the semiconductor substrate is subjected to a combination of polishing motions, including orbital motion, and at least one additional polishing motion selected from rotational, oscillating, sweeping, and linear polishing motions. The invention also provides an improved method for conditioning polishing pads to provide more uniform conditioning and to extend their useful life span.

Abstract: An apparatus for chemically and mechanically planarizing a workpiece surface employs a polishing slurry and a microreplicated pad having a surface for planarizing the workpiece surface in the presence of the slurry. The surface of the microreplicated pad has a regular array of structures having a sharp distal apexes which contact the workpiece surface during planarization and which are subject to ablating during planarizing thereby becoming substantially blunt. The workpiece moves in a rotational, orbital or translational motion relative to the microreplicated pad.

Abstract: A method and apparatus to generate an endpoint signal to control the polishing of thin films on a semiconductor wafer surface includes a through-bore in a polish pad assembly, a light source, a fiber optic cable, a light sensor, and a computer. The light source provides light within a predetermined bandwidth, the fiber optic cable propagates the light through the through-bore opening to illuminate the surface as the pad assembly orbits, and the light sensor receives reflected light from the surface through the fiber optic cable and generates reflected spectral data. The computer receives the reflected spectral data and calculates an endpoint signal by comparing the reflected spectral data with previously collected reference data. The comparison involves calculating an evaluation time based on the comparison, and calculating a difference time utilizing correlation to account for over polish/under polish. The endpoint is predicted utilizing the evaluation time and the difference time.

Abstract: The invention provides a method for differentially applying cleaning chemistries to a silicon wafer that has undergone a polishing process whether chemical mechanical polishing or polishing with a fixed abrasive material. In accordance with the invention, cleaning fluid with a specific chemistry designed for cleaning the front side of the wafer is applied to the front side; while different chemistry specifically selected for more effectively cleaning the rear side of the wafer is applied to that side. This application of different chemistries to the two sides of the wafer is referred to as “differential cleaning”.

Abstract: An apparatus and method for cleaning of disc-shaped objects, such as semiconductor wafers, employing a rotational fluid track. The cleaning may take place in a vertical cleaning chamber or optionally a horizontal cleaning chamber. Rotation of wafers is obtained without direct contact by motorized driver rollers that may have the potential of damaging the wafer. In preferred embodiments of the invention, a viscous shearing force is tangentially directed upon the surface of a wafer as the wafer rests upon support rollers within a cleaning chamber. Pressurized cleaning solutions are directed toward the wafer surface at an angle sufficient to impart a rotational force upon the wafer. In one embodiment of the invention, as the wafer spins within the cleaning chamber, a megasonic cleaning transducer is employed to enhance the surface cleaning process.

Abstract: A multiple wafer cleaning apparatus comprising a first module (12), having a first spaced-apart brush assembly having an inner brush (21a) and an outer brush (22a), each brush having a brush pad (102) and a platen (103), and a second module (14) having a second spaced-apart brush assembly (22) having an inner brush (22a) and an outer brush (22b), each brush having a brush pad (102) and a platen (103), each pair of spaced-apart, opposing, vertically disposed brushes (21) and (22) for scrubbing vertically disposed semiconductor wafers (25), in tanks (28). The two modularized sets of motorized, rotating, opposed, pancake shaped brushes (12) and (14), grip the freely rotating wafers (25) causing the wafers (25) to rotate in the same direction as the brushes.

Abstract: In a method for mathematically characterizing a multizone CMP carrier, alternating zones are pressurized to a first pressure and the remaining zones are pressurized to a second lower pressure. A first wafer may then be polished using this combination of pressures and a first material removal profile may then be found. The pressures in the zones may then be reversed, and a second wafer may then be polished using this new combination of pressures, and a second material removal profile may then be found. Symmetrical points of intersection about the central axis of the carrier may be determined which identify the radius of each zone, and each point corresponds to a middle point for each transitional area between zones. The absolute values for the first derivatives for two pairs of symmetrical points may be averaged to determine a set of parameters that allow the multizone carrier to be mathematically characterized.

Abstract: A method and apparatus for the in-process measurement of the thickness and composition of a material layer on a workpiece during chemical mechanical polishing are disclosed. The chemical mechanical polishing apparatus includes a platen having a polishing pad mounted thereto and an x-ray probe assembly mounted into a recessed volume in the platen. The x-ray probe assembly includes an x-ray emitter and an x-ray detector. The thickness and composition of the material layer on the workpiece is measured by generating and directing an incident x-ray beam onto a location on the surface of the wbrkpiece, and then capturing the resultant fluorescent beam and processing data from the resultant fluorescent beam.

Abstract: An electrochemical planarization apparatus for planarizing a metallized surface on a workpiece includes a platen, a conductive element disposed adjacent the platen and a polishing surface disposed adjacent the conductive element. A workpiece carrier is configured to carry a workpiece and press the workpiece against the polishing surface while causing relative motion between the workpiece and the polishing surface. A voltage source is configured to effect an electric potential difference between the metallized surface on the workpiece and the conductive element so that an electric field is produced between the metallized surface and the conductive element. The apparatus further includes a solution application mechanism configured to supply an electrolytic solution to the polishing surface.

Abstract: An apparatus and method for a spectrally stable light source is disclosed. An excitation source provides a spectrally stable light within a predetermined bandwidth. The spectrally stable light is directed at a reflective target. A light sensor receives reflected light from the surface of the target through the fiber optic cable and generates reflected spectral data. A computer receives the reflected spectral data and calculates a signal based on the reflected spectral data.

Abstract: The cleaning pads (102, 104) that are used to clean work pieces (200), such as semiconductor wafers, are cyclically compressed against one another and rinsed with a rinsing fluid. By cyclically compressing the cleaning pads (102, 104) together and rinsing them, the debris that the cleaning pads remove from the work pieces (200) and that becomes embedded in, and adhered to, the cleaning pads (102, 104) is subsequently removed therefrom.

Abstract: A method and apparatus for improving uniformity of the rate of removal of material from the surface of a workpiece, such as semiconductor substrate, by polishing. In accordance with the invention, the workpiece is subjected to a vibratory polishing method, and optionally at least one additional polishing motion selected from rotational, oscillating, sweeping, orbital and linear polishing motions. As a result, polished workpieces, such as semiconductor wafers, have reduced surface defects, improved planarity, and are polished more uniformly over a wider area.

Abstract: A wafer etching method wherein hydrogen gas, ammonia gas or mixed gas containing one of these gases is added to sulfur hexafluoride gas to suppress the occurrence of white turbidity on the surface of the wafer at the time of etching and to enable high quality mirror polishing of the wafer. In one embodiment, a mixed gas obtained by mixing SF6 gas G1 of a bomb 31 and H2 gas G2 of a bomb 32 in a predetermined ratio is fed to a discharge tube 2 and a microwave M is generated from a microwave oscillator 4 to cause plasma discharge. Further, the entire surface of the silicon wafer W can be flattened by locally etching the surface of the silicon wafer W by an activated species gas G sprayed from the nozzle portion 20.

Abstract: The present invention delineates a carrier for an apparatus (10) which polishes a surface of a semiconductor wafer (56, 124). In a preferred embodiment, the carrier includes a rigid plate (34) connected to one or more diaphragms (40, 42) of soft, flexible material that provide pressurizable cavities (50, 52) having respective surfaces for contacting the back surface of the wafer. A plurality of conduits (28a, 28c) are used to selectively pressurize the diaphragm cavities. The carrier head may also include an inter-diaphragm cavity (54) formed between a portion of one diaphragm, a portion of another diaphragm, and the semiconductor wafer. The inter-diaphragm cavity is provided with its own conduit (28b) by which a source of pressurized fluid and a source of vacuum are selectively connected to the inter-diaphragm cavity. During operation, pressure and/or vacuum may be applied through one or more cavities to chuck (90) a wafer, and to pressurize (96) the cavities during polishing.

Abstract: The invention is a chemical-mechanical polishing wafer carrier that is able to apply a plurality of different pressures, with minimal discontinuities at the interfaces between different pressures, through a diaphragm to a back surface of a wafer. A plurality of concentric balloons, that may be individually pressurized, is used to support and press on the back surface of the diaphragm. The walls of the balloons are preferably thin and elastic and preferably do not attach to the diaphragm. This helps to minimize any pressure discontinuities on the diaphragm along the interfaces between the balloons. A wafer may be placed against the front surface of the diaphragm allowing the front surface of the diaphragm to retain and press against the back surface of the wafer during a planarization process.

Abstract: The present invention provides a method of presenting a wafer to a metrology device for measuring surface characteristics of the wafer. In accordance with one aspect of the present invention, the metrology device is physically integrated with the wafer processing machine between two wafer processing stations. The metrology device measures the uniformity and or thickness of the wafer. In the preferred embodiment, the measuring device is a single wavelength multi-angle reflectometry device. The device comprises a light source provided from multiple emission points. In the preferred embodiment, the light source comprises a laser and the emission point comprise fiber optic cabling. In accordance with yet another aspect of the present invention, a wafer location means is provided to track the position of the wafer passing over the wafer measurement device.