Abstract: A CROSSATRON plasma switch has a peak current capability in excess of 10kA and a switching speed of at least 1.times.10.sup.11 A/sec, making it compatible with the requirements of excimer and CO.sub.2 gas laser switches, and yet is small enough to be mechanically integrated with such lasers. It employs an axially corrugated cathode with a body diameter on the order of 10 cm and shallow corrugations whose depths are about 1.0-1.5 times the distance between corrugations, together with a reduced diameter anode (of about 2.5 cm diameter for an excimer laser and about 1.25 cm diameter for a CO.sub.2 laser), to obtain a plasma volume of about 50-100 cm.sup.3 for rapid switching. A magnet assembly around the cathode uses only two stacked magnets, but has an overall greater axial length and surface magnetic strength than in prior switches. The magnet design produces a high field strength near the cathode, but without a significant extension of the field into the anode region.

Abstract: Focussed ion beam (FIB) implants (38,40) are used to set the threshold voltages of metal-oxide-semiconductor field-effect transistors (MOSFETs) in a selected logic gate (34,36) in a microelectronic integrated digital logic circuit (31) such that the direct current (DC) transfer function and logic thresholds are essentially the same as for another logic gate (30,32) which is not altered by FIB implants, but the switching speed is greatly reduced. This causes the altered gate (34,36) to switch in an apparently normal manner when tested under DC or low speed conditions, but to not switch at normal operating speed. The altered or disguised gate (34,36) is thereby always on or always off at the normal operating speed, whereas the unaltered gate (30,32) switches in the normal manner. This impedes attempts at reverse engineering since the circuit (31) operates differently under test and operating conditions, and the true logic functions of the gate (34,36) cannot be determined by known low speed test procedures.

Abstract: 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.

Abstract: A reactor 10 having a vacuum housing 30 which encloses a plasma chamber 14 is used to perform local plasma assisted chemical etching on an etchable substrate 12. The chamber 14 is movable and is sized according to the removal material footprint desired. An rf driven electrode 22 and rf driven gas diffuser 22 have the same diameter as the chamber 14. 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 reactive gas is flowed into the chamber with rf power so as to break the reactive gas into a plasma. The plasma chamber 14 which locally confines the plasma may be scanned over the substrate surface while the gap between the chamber and the substrate is varied to yield a desired etch profile.

Abstract: A chemically sensitive sensor capable of detecting changes in concentrations of ions, atoms, or molecules in a fluid environment in which the sensor is immersed or embedded comprises a thin clad optical fiber, which is coated with a polymer which is permeable to liquids and which contains a chemically sensitive material, and a light carrying fiber. The polymeric material has the ability to change color and/or absorbance when the concentration of the ion, atom, or molecule in the surrounding environment changes. The polymer will return to its original color and/or absorbance state once the concentration goes back to the original value. The color change or absorbance is detected through the core of the optical fiber which is connected to a photodetector. The coupling of the light into the sensing structure is obtained by using a core-only optical fiber, surrounded by a clad material, in addition to an external light source.

Abstract: A multiple missile ejection system (10) by which first and second missiles (14) and (16) are stored in a single launch tube (12). Each missile is ejected by a gas bag. In a particular embodiment, two gas bags are used. The first gas bag (18) is mounted between the first and second missiles (14) and (16) respectively. The second gas bag (20) is mounted between the second missile (16) and an end of the launch tube. When deflated, the first gas bag (18) has a longitudinal aperture (28) through the center thereof which allows for the ejection of the second missile (16) by the second gas bag (20).

Abstract: A surface (30) of a wafer of indium phosphide (22) is treated by first etching the surface (30) with an aqueous solution of nitric acid and ceric ammonium nitrate. A toughening solution of about 4 parts by volume of acetic acid, about 4 parts by volume nitric acid, and about 1 part by volume hydrobromic acid is prepared and mixed. The roughening solution is contacted to the etched surface (30) of the wafer of indium phosphide (22) for about 15 to about 30 seconds to roughen the surface of the indium phosphide. Reaction products may be removed from the surface in aqueous hydrofluoric solution, and metal may be deposited upon the toughened surface in a strongly adhering layer (28).

Abstract: A liquid fuel power plant (100) including an open-ended combustion chamber (102) and a first mechanism (110) for delivering a combustible fuel to the open-ended combustion chamber (102). A second mechanism (136) is included for igniting the fuel in the open-ended combustion chamber (102). A folded tubular mechanism (140) is provided for extending the length of the combustion chamber (102) to decompose the ignited fuel and to provide an exhaust gas comprised of fundamental elements. Finally, a third mechanism (160) is provided for using the exhaust gas to perform useful work. In a preferred embodiment the liquid fuel power plant (100) includes separate fuel and air inlet lines (110, 120). The air inlet line (120) delivers compressed air, which can be preheated, in an air passageway (130) and thereafter is mixed with the combustible fuel in the open-ended combustion chamber (102). An igniter (136) causes combustion of a compressed air-fuel mixture in an ignition region (118) of the combustion chamber (102).

Abstract: A spark-excited fluorescence sensor (10) is provided which enables monitoring of various gas species (14), such as H.sub.2, CO.sub.x, NO.sub.x, N2, NH.sub.x and hydrocarbons added to a system as source fuels and/or additive agents, or discharged from a system as exhaust including pollutants, for more efficient use of fuels for optimizing performance of the system, and, also, for reducing pollutants in the atmosphere. The spark-excited fluorescence sensor of the invention comprises a spark plug (12) to excite molecules of the gaseous species, an optical fiber window (18) and an optical fiber bundle (20) to collect and transmit, respectively, the fluorescence, bandpass filters ( 24 ) to select predetermined wavelengths corresponding to the gases to be detected, detectors (26), and signal processor (28 ) . The output from the signal processor is then used to improve overall performance of the system.

Abstract: A 3-dimensional opto-electronic system employs an optical communications channel between spaced circuit substrates. The beam from an in-line laser on one substrate is deflected by a turning mirror that is monolithically integrated on the substrate along with the laser and its associated electronic circuitry, and directed to an optical detector on another substrate. The deflection is accomplished with a turning mirror that is specially fabricated with a focused ion beam (FIB) so that it focuses or collimates as well as deflects the laser beam onto the photodetector. The mirror is initially formed with a flat surface, and is thereafter processed with the FIB to produce focusing curvatures in both x and y directions. The mirror is preferably spaced away from the laser, and is illuminated over substantially the full laser height to maximize its focal length for a given reflected spot size.

Abstract: A zero-degree mirror reflection hologram is embedded into a vehicle windshield to reduce veiling glare. The hologram partially reflects sunlight in the visible wavelength range incident on the windshield between 0 and substantially 70 degrees, and therefore blocks a substantial portion of visible sunlight that would otherwise pass through the windshield and reflect off the dashboard. The portion of light that does reflect off the dashboard which could enter the driver's eyebox does not reflect appreciably off the hologram because the hologram reflection peak is in the ultraviolet at high off-axis angles.

Abstract: A computer-aided expert system comprising a hypermedia structured expert system and a hypermedia-structured multi-level electronic document archive linked thereto. The expert system includes a knowledge base, an inference engine that interacts with the knowledge base to generate advice. A hypermedia interface having knowledge base transfer means is provided on a display that includes selectable areas that provide access to active and passive documents in the document archive. The document archive includes active and passive electronic documents interlinked by means of the hypermedia interface and linked to the expert system by means of the hypermedia interface. Each active and passive electronic document includes active document transfer means that provide for transfer from the active document to another active document, a passive document, or a knowledge base linked thereto.

Abstract: A measurement instrument which detects the thickness of the outer layer of a wafer 24, includes a filtered white light source forming an aperture image. The white light source includes a halogen lamp 10, a condensing lens 12, a circular aperture 14, a collimator lens 16, a narrow band filter wheel 18, and a second collimator lens 20. A monochromatic beam generated by this filtered white light source illuminates the entire surface of the wafer 24 with collimated light that has passed through a third collimator lens 22. The light reflected off the wafer 24 returns through the third collimator lens 22 and forms an aperture image upon an optical device which redirects this image to a charge coupled device (CCD) camera 30. The image is converted to a map of measured reflectance data by a digitizing circuit 34 and a computer 36. This map of measured reflectance data is then compared to reference reflectance data to generate a map of the outer layer thickness profile of the wafer 24.

Abstract: The positions of one or more underwater divers or vehicles are determined through an underwater acoustic communication link and at least a base buoy and one remote buoy with acoustic transponders and GPS position locating equipment. The location of the buoys is determined by the GPS equipment. The underwater diver or vehicle each carries an acoustic tracking unit transponder which emits a tracking unit message specifying its identity and its last known position at an assigned time slot. Upon reception of the tracking unit message by the base buoy, an acoustic base buoy message is emitted which includes the buoy position. The tracking unit receives the base buoy message, and marks the time of arrival to determine the propagation delay between the tracking unit and the base buoy. A predetermined delay after the receipt of the tracking unit message by the remote buoy, it sends an acoustic remote buoy message specifying its location.

Abstract: A cooperative differential drive system (20) for use in material handling and flight control and guidance systems, and the like. The drive system (20) may be employed in application that require high resolution task repeatability capabilities and the execution of precise position and force trajectory path following routines. A differential gear system (24) is driven by two servo-controlled actuators (22, 23) under control of a controller (21). The first actuator (22) is regulated at constant speed while the second actuator (23) is modulated at an appropriately varying speed to achieve a desired drive speed of a load. The second actuator (23) is controlled such that it dos not change rotational direction. Ultimate control of the load is achieved by way of the differential gear system (24) that combines the two actuator speeds to achieve the desired load speed. The differential gear system (24) is optionally coupled by way of a clutch system (25) to the load.

Abstract: A wide angle large reflective unobscured system (10) has a primary (12), secondary (14), tertiary (18) and fold (16) mirror. The primary (12) and secondary (14) mirrors act as a non-reimaging afocal telescope of the Galilean type and relay a virtual entrance pupil to the fold mirror (16) which is positioned at the system aperture stop. The fold mirror (16) directs the energy to the tertiary mirror (18) which acts to direct and focus the energy at a viewing plane. The resulting telescope provides a wide two dimensional field of view which can exceed 20.degree..times.40.degree., and operates at optical speeds about F/1.0.

Abstract: In a system for detecting gaseous emissions (10), a housing (20) encases a mechanical member such as a flanged coupling (21) of a closed mechanical system which contains a fluid such as a gas (11) and receives gas (11) escaping through the flanged coupling (21). A sensor (26) extends through the housing (20) into a cavity (22) formed by the housing (20). A semipermeable membrane (28) forming the union between the sensor (26) and housing (20) allows gas (11) encased by the housing (20) to slowly pass from the housing (20) while preventing foreign matter from entering the housing.

Abstract: A precision linear actuator (10, 120, 140) is provided particularly adapted for accurately controlling the positioning of a lens element in the optical system of a guided vehicle such as a missile. The actuator includes a frame (12, 130, 142) rigidly affixed to the missile structure which includes a pair of bearing supports (30, 32) and a pair of separated guide pockets (24, 26). A lever (14, 122, 150) is installed within the frame (12, 130, 142) and is fixed to the frame by bearings (44, 46) which enable the lever to undergo slight rotation with respect to the frame. An actuator mechanism in the form of a voice coil (56), drive motor or other device is employed to drive the lever (14, 122, 150) to undergo its rotational motion. A lens holder (16) is installed within an open area inside the lever (14, 122, 150) and defines separated guide rails (76, 78, 80, 82) which enable it to be moved linearly with respect to the frame (12, 130, 142).

Abstract: A low power white noise source is fabricated on an integrated circuit. The noise source includes a bipolar junction transistor (Q.sub.BJT) having an emitter terminal coupled to a common circuit potential, a collector terminal coupled to a source of current (CS), and a base terminal coupled through a resistance (R.sub.B) to a bias signal (V.sub.bias). The resistance has a resistance value selected to enhance a noise signal generated by the transistor in a collector current thereof. The noise source further includes a transresistance amplifier (AMP) having an input coupled to the collector terminal for converting the noise signal to a voltage signal (NOISE OUT) having white noise characteristics.

Abstract: Ionized metal cluster beam deposition of metal bumps on substrates such as multi-chip modules and integrated circuit chips is enhanced. The present invention discloses wet etching techniques for removing unwanted metal deposited on the substrate around bumps, multiple sources for depositing alloyed (tin-lead) bumps with constant composition, and single or multiple sources for directing a cluster beam through an aperture to deposit metal on a substrate and directing an ion beam at the aperture to remove metal deposited therein.