Abstract: A method for forming elongated articles including metallic oxide superconductor material by hydrostatic extrusion at temperatures less than about 800.degree. C., and even at temperatures less than about 450.degree. C. The method includes providing superconductive core material that is substantially free of carbon or organic additives and that has an equivalent density at least about 55% of full density, and enclosing the densified material in a metal container, to become a cladding, prior to extrusion. In a preferred embodiment, the cladding material is a dispersion hardened metal or metal alloy.

Abstract: An active optical device comprises a glass, waveguiding structure disposed on a substantially planar principal surface of a substrate. The structure includes a silica-based, erbium-doped active core. The active core has an erbium-to-silicon atomic ratio of at least about 0.01, an absolute erbium concentration of at least about 1.4.times.10.sup.20 atoms per cubic centimeter, and a radiative lifetime of the erbium lasing level of at least about 7 milliseconds. Also disclosed is a method for forming an active optical device, including the step of depositing an erbium-doped active core by sputtering.

Abstract: A bipolar transistor which is inherently bistable, is disclosed. This bipolar transistor has a structure such that the corresponding band diagram includes a first potential barrier within the collector, at or adjacent the base-collector interface. In addition, the band diagram also includes at least a second potential barrier within the collector.

Abstract: In an electronic circuit that normally includes a high-value resistor, the resistive function may be usefully provided by a thin dielectric layer. Electric current is transported through the layer by quantum tunneling. In one embodiment, a resistor useful for VLSI applications is provided, requiring only a single contact window.

Abstract: A method of forming silicon dioxide layers by bias ECR is described. The layers are formed by reacting oxygen with TEOS or TMCTS. High-quality, void-free layerc can be formed over conductor patterns having high-aspect-ratio intermetallic spacings.

Abstract: The method includes collapsing a silica-based glass tube to make a preform and drawing fiber from the preform. Prior to collapsing the tube, one or more glass layers are formed on the inner surface of the tube by dip-coating the surface with a sol comprising a metal alkoxide dissolved in an alcoholic or aqueous solvent, polymerizing the sol to form a gel, and drying and sintering the gel. A substantial portion the dopant, present within the sintered gel, diffuses into at least one adjoining glass region. A wide selection of dopant materials, in the form of salts or alkoxides, are readily incorporated by dissolving them in the solvent.

Abstract: Disclosed is a method for forming a silicon dioxide layer on a substrate by radio-frequency deposition from a plasma comprising oxygen, argon, and tetraethyl orthosilicate (TEOS) or tetramethyl cyclotetrasiloxane (TMCTS). A negative bias is imparted to the substrate. The resulting ion bombardment induces surface migration. Because TEOS and TMCTS have a relatively high mean free path for surface migration, the filling of soft spots and key holes is promoted.

Abstract: A method and apparatus are described for verifying handwritten, human signatures, and for permitting access to a system if such a signature is accepted. In an initializing stage, an authorized entrant submits a sample of multiple signatures. A first reference signature is selected from the sample, and a second reference signature is constructed by averaging over the sample. When a subsequent, prospective entrant submits a signature, a dynamic mismatch is calculated with respect to the first reference signature, and a shape mismatch is calculated with respect to the second reference signature. The signature is accepted if it satifies a predetermined criterion that refers to the dynamic and shape mismatch values.

Abstract: A novel probe, useful for near-field optical scanning microscopy, is provided. The probe has a fine tip which includes fluorescent material. In one embodiment, the invention is an apparatus which includes such a probe, means for exciting and detecting fluorescence in the probe tip, means for positioning the probe tip near the surface of a sample, and means for displacing the probe tip relative to the sample. In a second embodiment, the invention is a manufacturing method in which the novel probe is used to measure a characteristic dimension of a patterned workpiece.

Abstract: Disclosed is a method for manufacturing an integrated circuit which includes the step of evaluating the reliability of metal films in the circuit using a noise measurement technique. In one embodiment, a film portion to be tested is incorporated in a Wheatstone bridge. A relatively large direct current is passed through the film to stimulate 1/f.sup.2 noise. A relatively small alternating current is concurrently passed through the film. The bridge imbalance signal at the ac frequency is amplified and demodulated by a phase-locked amplifier, and is then frequency analyzed. The film is evaluated by comparing the resulting noise power spectrum with predetermined standards.

Abstract: Disclosed is a planar optical waveguide that is manufacturable by the compression molding or embossing of a multilayer film of polymeric material. In one embodiment, the waveguide comprises a core layer of relatively high refractive index included between cladding layers of lower refractive index. The waveguiding channels are bounded by regions where the cladding layers are in contact and from which core material has been excluded.

Abstract: The invention relates to optical systems comprising thin film optical waveguide isolators that are characterized by linear birefringence at least some wavelengths and temperatures. Disclosed is a method for using such a system at more than one wavelength and temperature.

Abstract: Disclosed is a digital communication system including a remotely operable switch. Messages from sending means to receiving means in the system are intercepted by hard wired, character-recognition means withing the switch. When a message contains an activating character sequence, the switch is activated, closing an external circuit. The switch may be powered on independently of whether the receiving means are powered on or off.

Abstract: An electro-optic medium, useful for image processing, is formed by creating a distribution of deep impurity levels over essentially all the lateral extent of a multilayer heterostructure. This treatment renders the heterostructure semi-insulating, and as a consequence, individual image-resolution elements are isolated. Described is an optical system comprising such an electro-optic medium.

Abstract: Disclosed is apparatus comprising an electrostatic cassette assembly for securing a semiconductor wafer during lithographic processing such as direct-write particle-beam lithography. The cassette assembly comprises a cassette body and an electrostatic chuck installable in, and removeable from, the cassette body. The electrostatic chuck comprises a charge plate having a thin dielectric layer on its upper surface, against which the wafer is flattened by Coulombic force. Charge storage means are included for maintaining an electrical potential difference between the wafer and the charge plate even in the absence of connection to a source of electrical energy external to the assembly.