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Lloyd A. Hackel, Alan K. Burnham, Bernardino M. Penetrante, Raymond M. Brusasco, Paul J. Wegner, Lawrence W. Hrubesh, Mark R. Kozlowski, Michael D. Feit
Method for Producing Damage Resistant Optics
U.S. Patent 6,518,539 B2
February 11, 2003
A system that mitigates the growth of surface damage in an optic. In an embodiment of the invention, damage sites in the optic are initiated, located, and then treated to stop the growth of the damage sites. The step of initiating damage sites in the optic includes a scan of the optic with a laser to initiate defects. The exact position of the initiated sites is identified. A mitigation process is performed that locally or globally removes the cause of subsequent growth of the damaged sites.

Donald A. Masquelier, Fred P. Milanovich, Klaus Willeke
High Air Volume to Low Liquid Volume Aerosol Collector
U.S. Patent 6,520,034 B1
February 18, 2003
A high-air-volume to low-liquid-volume aerosol collector. A high-volume flow of aerosol particles is drawn into an annular, centripetal slot in a collector that directs the aerosol flow into a small pool of liquid contained in a lower center section of the collector. The annular jet of air impinges upon the liquid, embedding initially airborne particles in the liquid. The liquid in the pool continuously circulates in the lower section of the collector by moving to the center line, then upward, and then, with assistance from a rotating deflector plate, passes back into the pool at the outer area adjacent to the impinging air jet. The air jet moves upward through the liquid pool, through a hollow center of the collector, and is then discharged via a side outlet. Any liquid droplets escaping with the effluent air are captured by a rotating mist eliminator and moved back toward the liquid pool. The collector includes a sensor assembly for determining, controlling, and maintaining the level of the liquid pool. It includes a lower, centrally located valve assembly connected to a liquid reservoir and to an analyzer for analyzing the particles that are impinged into the liquid pool.

Kenneth M. Skulina, Richard M. Bionta, Daniel M. Makowiecki, Craig S. Alford
Method for Fabricating Beryllium-Based Multilayer Structures
U.S. Patent 6,521,101 B1
February 18, 2003
A process for fabricating beryllium-based multilayer mirrors useful in the wavelength region greater than the beryllium K-edge (11.1 nanometers). The process includes alternating sputter deposition of beryllium and a metal—typically from the fifth row of the periodic table—such as niobium, molybdenum, ruthenium, and rhodium. The process includes not only the method of sputtering the materials but also the industrial hygiene controls for safe handling of beryllium. The mirrors made in accordance with the process may be used in soft x-ray and extreme ultraviolet project lithography, which requires mirrors of high reflectivity (greater than 60 percent) for x rays in the range of 6.0 to 14.0 nanometers.

Walter B. Lindquist, Patrick A. Kearney
Ion Beam Collimating Grid to Reduce Added Defects
U.S. Patent 6,521,897 B1
February 18, 2003
A collimating grid located after the exit grid of an ion source that collimates the ion beamlets, disallows beam spread, and limits beam divergence during transients and steady-state operation. The additional exit or collimating grid prevents beam divergence during turn-on and turn-off and prevents ions from hitting the periphery of the target where there is redeposited material. Or it prevents ions from missing the target and hitting the wall of the vessel where there is deposited material, thereby preventing defects from being deposited on a substrate to be coated. Thus, the addition of a collimating grid to an ion source ensures that the ion beam will hit and be confined to a specific target area.

M. Allen Northrup, Yun-Tai Hsueh, Rosemary L. Smith
Microfabricated Electrochemiluminescence Cell for Chemical Reaction Detection
U.S. Patent 6,521,181 B1
February 18, 2003
A detector cell for a silicon-based or nonsilicon-based sleeve-type chemical reaction chamber that combines heaters, such as doped polysilicon for heating and bulk silicon for convection cooling. The detector cell is an electrochemiluminesence cell constructed of layers of silicon with a cover layer of glass. It has electrodes spaced between various layers forming the cell. The cell has a cavity into which fluid inlets direct reaction fluids. The reaction chamber and detector cell may be used in any chemical reaction system for synthesis or processing of organic, inorganic, or biochemical reactions, such as the polymerase chain reaction, or other DNA reactions, such as the ligase chain reaction. These are examples of synthetic, thermal-cycling-based reactions. The electroluminescence cell may also be used in synthesis instruments, particularly those for DNA amplification and synthesis.

Matthew J. Everett, Billy W. Colston, Jr., Ujwal S. Sathyam, Luiz B. Da Silva, Daniel Fried
Optical Detection Dental Disease Using Polarized Light
U.S. Patent 6,522,407 B2
February 18, 2003
A polarization-sensitive optical imaging system is used to detect changes in polarization in dental tissues to help diagnose diseases such as caries. The degree of depolarization is determined by illuminating the dental tissue with polarized light and measuring the polarization state of the backscattered light. The polarization state of this reflected light is analyzed with optical polarimetric imaging techniques. A handheld fiber-optic dental probe is used in vivo to direct the incident beam to the dental tissue and collect the reflected light. For depth-resolved characterization of the dental tissue, the polarization diagnostics may be incorporated into optical coherence domain reflectometry and optical coherence tomography systems, which enable identification of subsurface depolarization sites associated with demineralization of enamel or bone.

M. Allen Northrup
Microfabricated Sleeve Devices for Chemical Reactions
U.S. Patent 6,524,532 B1
February 25, 2003
A silicon-based sleeve-type chemical reaction chamber that combines heaters, such as doped polysilicon, and bulk silicon for convection cooling. The reaction chamber combines a critical ratio of silicon- and nonsilicon-based material to provide the desired thermal properties. For example, the chamber may combine a critical ratio of silicon and silicon nitride to the volume of material to be heated (for example, a liquid) in order to provide uniform heating at low power requirements. The reaction chamber will also allow the introduction of a secondary tube (for example, plastic) into the sleeve containing the reaction mixture, thereby alleviating any potential material incompatibility issues. The reaction chamber may be used in any chemical reaction system for synthesis or processing of organic, inorganic, or biochemical reactions, such as the polymerase chain reaction, and other DNA reactions, such as the ligase chain reaction. These are examples of synthetic, thermal-cycling-based reactions. The reaction chamber may also be used in synthesis instruments, particularly those for DNA amplification and synthesis.

Matthias Frank, Carl A. Mears, Simon E. Labov, Larry J. Hiller, Andrew T. Barfknecht
Cryogenic High-Resolution X-Ray Detector with High Count Rate Capability
U.S. Patent 6,528,814 B1
March 4, 2003
A cryogenic high-resolution x-ray detector with high count rate capability. The new detector is based on superconducting tunnel junctions and operates without thermal stabilization at or below 500 millikelvins. The x-ray detector exhibits good resolution (approximately 5 to 20 electronvolts full width at half-maximum) for soft x rays in the kiloelectronvolt region and is capable of count rates of more than 20,000 counts per second. Simple field-effect-transistor–based charge amplifiers, current amplifiers, or conventional spectroscopy–shaping amplifiers can provide the electronic readout of this x-ray detector.

Marcel L. van den Berg, Jan D. Batteux, Simon E. Labov
Electro-Mechanical Heat Switch for Cryogenic Applications
U.S. Patent 6,532,759 B1
March 18, 2003
A heat switch includes two symmetric jaws. Each jaw is composed of a link connected at a translatable joint to a flexible arm. Each arm rotates about a fixed pivot and has an articulated end that includes a thermal contact pad connected to a heat sink. The links are joined together at a translatable main joint. To close the heat switch, a closing solenoid is actuated and forces the main joint to an over-center position. This movement rotates the arms about their respective pivots, forces each of them into a stressed configuration, and forces the thermal contact pads toward each other and into compressive contact with a cold finger. The closing solenoid is then deactivated. The heat switch remains closed because of a restoring force generated by the stressed configuration of each arm, until actuation of an opening solenoid returns the main joint to its starting open-switch position.

Alexis E. Schach Von Wittenau
Correlated Histogram Representation of Monte Carlo Derived Medical Accelerator Photon-Output Phase Space
U.S. Patent 6,535,837 B1
March 18, 2003
A method is provided to represent the calculated phase space of photons emanating from medical accelerators used in photon teletherapy. The method reproduces the energy distributions and trajectories of the photons originating in the bremsstrahlung target and the photons scattered by components within the accelerator head. The method reproduces the energy and directional information from sources up to several centimeters in radial extent, so it is expected to generalize well to accelerators made by different manufacturers. The method is computationally fast and efficient, with overall sampling efficiency of 80 percent or higher for most field sizes. The computational cost is independent of the number of beams used in the treatment plan.

Dianne D. Gates-Anderson, Scott D. Kidd, John S. Bowers, Ronald W. Attegery
HEPA Filter Encapsulation
U.S. Patent 6,537,350 B2
March 25, 2003
A low-viscosity resin is delivered into a spent HEPA filter or other waste. The resin is introduced into the filter or other waste using a vacuum to assist in the mass transfer of the resin through the filter media or other waste.

Steven R. Visuri, Beth M. Mannimini, Luiz B. Da Silva, Peter M. Celliers
Bubble Diagnostics
U.S. Patent 6,538,739, B1
March 25, 2003
A means of diagnosing the presence of a gas bubble and incorporating the information into a feedback system for optoacoustic thrombolysis. In optoacoustic thrombolysis, pulsed laser radiation at ultrasonic frequencies is delivered intraluminally down an optical fiber and directed toward a thrombus or otherwise occluded vessel. Dissolution of the occlusion is therefore mediated through ultrasonic action of propagating pressure or shock waves. A vapor bubble in the fluid surrounding the occlusion may form as a result of laser irradiation. This vapor bubble may be used to directly disrupt the occlusion or as a means of producing a pressure wave. It is desirable to detect the formation and follow the lifetime of the vapor bubble. Knowledge of the bubble formation and lifetime yields critical information as to the maximum size of the bubble, density of the absorbed radiation, and properties of the absorbing material. This information can then be used in a feedback system to alter the irradiation conditions.

Daniel Toet, Thomas W. Sigmon
Process for Direct Integration of a Thin-Film Silicon P-N Junction Diode with a Magnetic Tunnel Junction
U.S. Patent 6,541.316 B2
April 1, 2003
A process for direct integration of a thin-film silicon p-n junction diode with a magnetic tunnel junction for use in advanced magnetic random access memory cells of high-performance, nonvolatile memory arrays. The process is based on pulsed laser processing for the fabrication of vertical polycrystalline silicon electronic device structures, in particular p-n junction diodes, on films of metals deposited on low-temperature substrates such as ceramics, dielectrics, glass, or polymers. The process preserves underlayers and structures onto which the devices are typically deposited, such as silicon integrated circuits. The process involves the low-temperature deposition of at least one layer of silicon, either in an amorphous or a polycrystalline phase on a metal layer. Dopants may be introduced in the silicon film during or after deposition. The film is then irradiated with short-pulse laser energy, which is efficiently absorbed in the silicon, resulting in the crystallization of the film and simultaneously in the activation of the dopants by ultrafast melting and solidification. The silicon film can be patterned either before or after crystallization.

John F. Holzrichter, Greg C. Burnett, Lawrence C. Ng
System and Method for Characterizing, Synthesizing and/or Canceling Out Acoustic Signals from Inanimate Sound Sources
U.S. Patent 6,542, 857 B1
April 1, 2003
A system and method for characterizing, synthesizing, and/or canceling out acoustic signals from inanimate sound sources. Propagating-wave electromagnetic sensors monitor excitation sources in sound-producing systems, such as machines, musical instruments, and various other structures. Acoustical output from these sound-producing systems is also monitored. From such information, a transfer function characterizing the sound-producing system is generated. From the transfer function, acoustical output from the sound-producing system may be synthesized or canceled. These methods enable accurate calculation of matched transfer functions relating specific excitations to specific acoustical outputs. Knowledge of such signals and functions can be used to effect various sound replication, sound source identification, and sound cancellation applications.

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