Abstract: The present invention provides a method for monitoring a modifying-process taking place in a thin-film sample and thereby characterizing the sample thus modified, wherein the modifying-process is performed for purpose of improving physical properties of the sample. The present invention further provides a monitoring tool for characterizing various thin-film processes. Advantages of the method of the present invention are manifest in its non-intrusive nature, fast (or real-time) response, robust sensitivity, and versatility in a variety of thin-film processes. Another inherent advantage of the present invention is that an assortment of the “n&k” parameters can be obtained by using only measurement tool, in contrast to two (or more) simultaneous measurement tools used in the prior art.

Abstract: A system for docking a floating test stage with integrated testing equipment to a predetermined position relative to a terrestrial base is described. The system includes a cylinder for docking the test stage to the predetermined position and a vibration isolation system for isolating the test stage when it is floating over the base. The system also includes a handling unit indexed to the predetermined position for loading and unloading samples on the test stage.

Abstract: A method and an apparatus for optically determining a physical parameter such as thickness t, index of refraction n, extinction coefficient k or a related physical parameter such as energy bandgap Eg of a thin film. A test beam having a wavelength range &Dgr;&lgr; is used to illuminate the thin film after it is deposited on a complex substrate which has at least two layers and exhibits a non-monotonic and an appreciably variable substrate optical response over wavelength range &Dgr;&lgr;. Alternatively, the thin film can be deposited between the at least two layers of the complex substrate. A measurement of a total optical response, consisting of the substrate optical response and an optical response difference due to the thin film is performed over wavelength range &Dgr;&lgr;. The at least two layers making up the complex substrate are chosen such that the effect of multiple internal reflections in the complex substrate and the film is maximized.

Abstract: A graded anti-reflective coating (ARC) with one or more layers has a bottom layer that is highly absorbing at the lithographic wavelength, and one or more layers between the substrate and the resist layer having inhomogeneous optical constants. The refractive indices are matched across layer interfaces, and the optical constants vary smoothly through the layer thicknesses. In each layer the extinction coefficient and the refractive index have independently selectable values and gradients. This ARC structure provides almost total absorption in the bottom layer and near-zero reflection at the resist interface and all other intermediate interfaces. Layers are preferably of inorganic materials, typically SiOxNy. Because of its highly absorbing bottom layer, an ARC according to an embodiment of the present invention works effectively over diverse substrate materials for a variety of lithographic wavelengths. It provides great latitude of manufacturing tolerances for thicknesses and optical constants.

Abstract: An apparatus uses reflectance spectrophotometry to characterize a sample having any number of thin films. The apparatus uses two toroidal mirrors in an optical relay to direct light reflected by the sample to a spectroscopic device. A computer then analyzes the reflected spectrum to characterize the optical properties of the sample. The optical relay allows a range of angles of reflection from the sample, and has no chromatic aberration. The optical relay is also arranged so that the non-chromatic aberration is minimized. For polarization-based measurements polarizing elements can be used in the apparatus and the spectroscopic device can be a spectroscopic ellipsometer. The sample is mounted on a movable stage so that different areas of the sample may be characterized. Furthermore, a deflector and a viewer are used to allow the operator of the apparatus to view the region of the sample under study.

Abstract: A method and apparatus for optically determining a physical parameter of an underlayer such as the underlayer refractive index N.sub.u, extinction coefficient k.sub.u and/or thickness t.sub.u through a top layer having a first top layer thickness t.sub.1 and an assigned refractive index index n.sub.t and coefficient of extinction k.sub.t. The values of index n.sub.t and extinction coefficient k.sub.t can be estimated, optically determined or assigned based on prior knowledge. In a subsequent step a first reflectance R.sub.1 is measured over a wavelength range .DELTA..lambda. by using a test beam spanning that wavelength range. Then, a second reflectance R.sub.2 of the top layer and underlayer is measured using the test beam spanning wavelength range .DELTA..lambda. at a second top layer thickness t.sub.2. In a calculation step the physical parameter of the underlayer is determined from the first reflectance measurement R.sub.1, the second reflectance measurement R.sub.

Abstract: An apparatus for rotationally positioning a disk on a stationary stage at a constant and repeatable distance and angle for a device to perform an operation on several positions of the disk surface is disclosed. The disk apparatus has a manipulating member that operates from a central portion of the stationary stage. The member raises the disk, rotates the disk to a new position and sets the disk back down on a planar portion of the same stationary stage. The apparatus uses vacuum to secure the disk to the stage and to the member during manipulation. The member is raised by a spring and lowered by vacuum. The apparatus is easily incorporated into an optical system for performing reflectance and transmitance on both side of the disk simultaneously allowing for the analyses of the disk layers for composition and consistency.

Abstract: An optical device for measuring reflectance, and, optionally, transmission, of a substrate. The device has first and second toroidal mirrors and first and second optical fibers. The first toroidal mirror directs light from the first optical fiber toward the substrate, which reflects from the substrate and is collected by the second toroidal mirror. The light collected by the second toroidal mirror is focused into the second optical fiber. There are many possible orientations for the fibers and mirrors. The device may also have a fold mirror for directing the light toward the substrate. Optionally, the present invention includes components for measuring transmission of the substrate. The components for measuring transmission may include fibers and toroidal mirrors. Preferably, reflectance and transmission are measured at the same location. If a fold mirror is used, the fold mirror has a gap to allow transmission measurements to be performed at the same location as reflectance measurements.

Abstract: An apparatus uses reflectance spectrophotometry to characterize a sample having any number of thin films. The apparatus uses two toroidal mirrors in an optical relay to direct light reflected by the sample to a spectrophotometer. A computer then analyzes the reflected spectrum to characterize the optical properties of the sample. The optical relay allows a range of angles of reflection from the sample, and has no chromatic aberration. The optical relay is also arranged so that the non-chromatic aberration is minimized. The sample is mounted on a movable stage so that different areas of the sample may be characterized. Furthermore, a deflector and a viewer are used to allow the operator of the apparatus to view the region of the sample under study.

Abstract: The invention comprises an apparatus for characterizing a thin film using the reflected spectrum of the film. The apparatus uses two toroidal mirrors in an optical relay to direct light onto the thin film and to direct reflected light from the film to a spectrophotometer. A computer then analyzes the reflected spectrum to characterize the optical properties of the thin film. The optical relay allows for a range of angles of incidence upon the sample, and has no chromatic aberration.

Abstract: The present invention provides improvements in the design of radial flexures and beam-columns used in vibration isolation systems which rely on a principle of loading a particular elastic structure which forms the isolator or a portion of it to approach the elastic structure's point of elastic instability. The improved radial flexure includes a region along the flexure in which there is reduced stiffness than the stiffness substantially along the length of the flexure. In one preferred form of the invention, the region of reduced stiffness is created by machining or forming a notch near each end of the flexure. Likewise, the improved design of the beam-column includes a region in which the stiffness of the beam-column in less than the stiffness along substantially the length of the beam-column. In one preferred embodiment, the region of reduced stiffness of the beam-column is formed by machining or otherwise forming notches near the ends of the beam-column.

Abstract: An auto-adjust apparatus adjusts a vibration isolator to help accommodate varying weight loads and other effects which can cause the isolator to go out of adjustment, such as variations caused by changes in ambient temperature and creep of the isolator's main support spring. A small secondary spring is positioned in parallel with the main support spring of the isolator and is precompressed such that its compression increases the load on the main support spring by a small amount. An increase in the compression of this secondary spring will cause an increase in the load on the main support spring. Similarly, a decrease in the compression on this secondary spring will cause a decrease in the load on the main support spring. Sensors for sensing a deviation in the equilibrium position of the object relative to the base from its optimum equilibrium position are provided and generate an electrical signal indicating such deviations.

Abstract: An improved version of vibration isolation systems using negative stiffness incorporates a payload and payload platform on just one 6-DOF isolator in a unique and innovatively compact configuration. The isolator includes a platform supported on an assembly of independently acting flexure mechanisms which are connected in serial fashion, tilt on top of horizontal on top of vertical, and in turn connected a base. Proper arrangement of the mechanisms and the payload/platform center of mass provides highly effective decoupled isolator performance. In addition, an innovative flexure preloading method which significantly improves vertical isolation performance is incorporated. This method can be used with prior (unsymmetric) designs or combined with a set of shear flexures in an innovative symmetric arrangement described below to provide more assurance of ideal decoupled response to mutually perpendicular base excitation input.

Abstract: An improved omnidirectional vibration isolating suspension apparatus for supporting an object in an equilibrium position relative to a base while suppressing transmission of vibratory motion between the object and the base, in which an isolator internal structure resonant frequencies can be significantly increased while the isolator provides low vertical and horizontal stiffness and low resonant frequencies.

Abstract: A method for producing potassium carbonate using a continuous countercurrent exchange system. A continuous ion exchange system with resin in the ammonium form is flushed with a saturated potassium chloride solution which displaces the ammonium ion and replaces it with potassium. Ammonium carbonate is then passed through the ion exchanger to place the ammonium in the reserve form, by displacing the potassium, and produce a concentrated potassium carbonate solution. This process is done in a continuous countercurrent manner which allows maximum recovery of the potassium carbonate as a 15-18% by weight solution with minimum impurities, and at high throughput rates. The potassium carbonate solution is then removed, evaporated, dried, sized and stored for subsequent shipment.

Abstract: An improved vibration isolation system utilizes at least one pair of structures connected vertically in series with each other and with a base structure and preloaded vertically, with a payload platform disposed between and connected to the structures. Each structure has a negative-stiffness effect in response to vertical compressive load for reducing its horizontal stiffness. The system passively accommodates changes in payload weight or weight distribution by providing a prescribed change in horizontal-motion isolator stiffness with change in weight load. The invention also provides an improved means of retrofitting existing vibration-isolating suspension systems to reduce their stiffness and increase their damping.

Abstract: An improved vibration isolation system utilizes a damped elastic structure loaded to approach a point of elastic instability to reduce the stiffness of the structure and to increase the damping. The system provides very low amplification at system resonant frequencies and effectively isolates at higher frequencies.

Abstract: A vibration isolation system utilizes various configurations of elastic structures loaded to approach a point of elastic instability. In one form of the invention, the system uses a combination of a negative-stiffness mechanism and a positive spring to support a payload and provide low net stiffness in the vertical direction. Horizontal motion is generally isolated by utilizing one or more axially-symmetric columns loaded to approach their critical buckling loads to provide low stiffness in any horizontal direction.

Abstract: A variable pressure power cycle and control system that is adjustable to a variable heat source is disclosed. The power cycle adjusts itself to the heat source so that a minimal temperature difference is maintained between the heat source fluid and the power cycle working fluid, thereby substantially matching the thermodynamic envelope of the power cycle to the thermodynamic envelope of the heat source. Adjustments are made by sensing the inlet temperature of the heat source fluid and then setting a superheated vapor temperature and pressure to achieve a minimum temperature difference between the heat source fluid and the working fluid.