Showing papers on "Fabrication published in 1979"

Fabrication of an integrated, planar silicon ink-jet structure

Abstract: A new design and fabrication technique for ink-jet nozzles fabricated from silicon is described. The single,

Air film system for handling semiconductor wafers

Abstract: In an automated fabrication facility, the thin, fragile silicon wafers in which semiconductor circuits are formed must be transported to and from processing stations with a minimum of contact with other solid objects so as to minimize damage, contamination, and consequent lowering of product yield. This task has been undertaken for some time now, in IBM and elsewhere, by systems based on a lubricating film of air as a means for levitating and moving wafers. However, due to inherent motion instabilities and specific control needs, some solid contact is typically involved in effecting prescribed wafer motion. The need for solid contact control is greatly reduced by the air film system described in this paper. It is based on a surface configuration that combines two fluid mechanics phenomena to generate a supporting air film that provides and guides wafer motion. Wafer transportation and positioning are achieved with the air film operating in conjunction with special control device techniques.

Quartz tube orifice leaks for local, fast-response gas sampling to mass spectrometers.

Abstract: Simple and versatile quartz tube orifice leaks, suitable for sampling of gas mixtures to mass spectrometers, have been made by heating the tip of a quartz tube in a hydrogen–oxygen flame. With these leaks the requirement of expensive and clumsy differential pumping stages is removed. The quartz probes have been used in gas sampling from catalytic reaction cells at 1 atm to a mass spectrometer. The sampling position can be located within 0.1 mm from the catalyst. Continuous recording of the local gas composition is then achieved with a response time of about 0.05 s, and with a minimum perturbation of the gas flow. The probes have been used in ambient air and at temperatures around 1000 K for extended periods of time without deterioration or plugging. The high stability at elevated temperatures and chemical resistance seem to make these probes useful for various applications, e.g., in sampling from combustion flames. The gas flow through the leak is determined by a very short and narrow constriction at the ...

A tantalum-on-sapphire microelectrode array

Abstract: The design and fabrication are described of a new microelectrode array for the production of localized electrical excitation in nerve fibers, in particular in the auditory nerve. The sapphire substrate was chosen for its electrical (insulating) and mechanical properties, tantalum was chosen as the conductor metal because of its self-passivating characteristics, and platinum as the stimulation electrode material because of its resistance to electrolysis. Experimental measurements are presented to show the effectiveness of Ta 2 O 5 as an insulator in biphasic charge delivery systems, and the effectiveness of conformal dielectric overcoating of the Ta 2 O 5 in reducing capacitive signal leakage is demonstrated. The electrochemical properties of the platinum-electrolyte interface are shown to provide a satisfactory model on which to estimate the charge delivery capabilities of the electrodes. Finally, the sequence of process-compatible steps for fabricating the microelectrode array, from the first tantalum deposition to the final overcoating are detailed.

Fabrication of isolated regions for use in self-aligning device process utilizing selective oxidation

Abstract: V-shaped lateral dielectric isolation grooves divide a semiconductor layer into a plurality of regions. The oxide layer above the polycrystalline material in the grooves is thicker than the field oxide layer on the semiconductor layer to prevent the creation of retrograde surface profiles and mask the polycrystalline material during self-aligned device fabrication in the semiconductor layer. The field oxide is formed on the semiconductor layer before the isolation groove fabrication and prevented from increasing in thickness by an oxide inhibiting layer during the isolation groove fabrication.

Fabrication of electrodes for electromagnetic flowmeter - uses powdery or fibrous particles of conductive substance embedded in insulating lining

Abstract: The electrodes obtain the measuring voltage, or are used for earthing. They are in contact with the liquid medium flowing through the tubular measured value generator. The tube has on its inner surface an insulating lining. The electrodes consist of powdery or fibrous particles of a conductive substance, embedded into the insulating lining in the electrode zone(s). The particles are of carbon, graphite, or metal. The electrode structure may incorporate a metal mesh coupled to the current conductor. The measuring electrodes, to which the measuring voltage is applied, may be arranged on diametrically opposite sides of the tube. An electrode plate may be secured to each measuring electrode by a dielectric adhesive. Annular electrodes at the tube ends may form earthing rings.

Extremely sensitive super conducting quantum interference device constructed as a double-helix array

Abstract: The instant invention increases the sensitivity of Josephson Junction Cryogenic Magnetometers by the use of stacked SQUID arrays The SQUID sensitivity at each sensing point is increased by making an intimate, co-axial superposition of two or more two-junction DC SQUID loops, using evaporated thin-film technology although fabrication is not limited to this technology The device permits multiple use of the SQUID loop area, thereby increasing the sensing volume and improving the coupling to the ambient magnetic field

Fabrication of hemispherical structures using semiconductor technology for use in thermonuclear fusion research

Abstract: Initial investigations and laboratory experiments in the area of target fabrication using solid state circuit processing techniques to create special target components have indicated the feasibility of a unique advanced manufacturing concept. A question of the applicability of silicon integrated circuit technology and how it might be applied to the fabrication of inertial confinement fusion targets was posed. The combined efforts of the University of Michigan Electron Physics Laboratory, and the Division of Material Sciences of KMS Fusion, Inc. have provided some relatively quick and very encouraging answers and results. The initial efforts to demonstrate electron beam patterning and etching of micron‐high letters through the walls of glass microballoons, the fabrication of free‐standing thin‐walled flanged hemispheres joined to form spherical structures, and a pellet support membrane have been the proof‐of‐principle milestones and goals.

Development and production of superconducting resonators for the argonne heavy ion linac

Abstract: The first six niobium split-ring resonators for the Argonne Heavy-Ion Energy Booster have been completed. The average performance at 4.2K is an accelerating gradient of 3.7 MV/m or an effective accelerating potential of 1.3 MV per resonator for an rf input of 4 W/resonator. The resonators are constructed in part of an explosively bonded Nb-Cu composite material which performs well for rf surface fields of at least 200 G. In initial tests, the resonators frequently exhibit thermal instability at E a < 3 MV/m because of several types of microscopic surface defects. The methods used for locating, identifying, and removing these defects are discussed.

Fabrication of superconducting Nb3Sn‐Cu composites

Abstract: A new process has been developed for the fabrication of multifilamentary composites of Nb3Sn in a Cu matrix. Dendritic Cu‐Nb alloys are cast as 2.5‐kg billets and extruded to a tube shape. The core of the tube is filled with a Sn–5 wt% Cu alloy, and the assembly is drawn to 0.015‐cm‐diam wire with no intermediate anneals. Reaction of the wire at 550 °C for two days gives a product suitable for magnets in the 8–14‐T range.

Magnetic bubble device scaling and density limits

Abstract: Scaling of magnetic bubble devices to smaller bubble sizes and higher density is considered. Drive field requirements, materials requirements, fabrication requirements, current requirements, and detector signal-to-noise ratio are all calculated as a function of bubble size and related to practical limits imposed by bubble materials, fabrication techniques, and electromigration limits. It is concluded that "conventional" bubble devices using Permalloy bars can be made practical with 1-μm bubble domains (storage density \sim6 \times 10^{6} bits/cm2). Although it may be possible to extend these Permalloy bar devices to even smaller bubbles, it seems more likely that other bubble devices such as contiguous disk devices or bubble lattice devices will in fact be used for densities greater than 6 × 106bits/cm2.

X‐ray lithographic patterning of magnetic bubble circuits with submicron dimensions

Abstract: An x‐ray process is described which permits the fabrication of submicrometer single level masking bubble devices. The process includes electron‐beam patterning of the master x‐ray mask followed by a CuLα x‐ray copy to pattern a negative x‐ray mask. Enhancements of electron‐beam lithography are described which permit fabrication of 1/4 μm mask structures with 70 A resolution. The x‐ray process is applied to the SLM fabrication of 1 μm magnetic bubble devices with 1/2 μm features, and propagation characteristics of these devices are reported.

Method of production multifilamentary intermetallic superconductors

Abstract: A method of making A-15 type intermetallic superconductors is disclosed which features elimination of numerous annealing steps. Nb or V filaments are embedded in Cu matrices; annular layers of Sn or Ga, respectively, separated from each other by Cu layers, provide the other component of the intermetallic superconductors Nb 3 Sn and V 3 Ga.

Direct device fabrication by selected area e‐beam annealing

Abstract: A flexible scanning electron‐beam system for annealing ion‐implanted semiconductors or partially processed devices, direct device fabrication, or other high flux thermal processing is described. A maximum beam current of 3 mA in a 40 μm spot is available at accelerating voltages of up to 30 kV. Microprocessor controlled scanning over a 10 mm square field is available in this system. Resistor structures and diode arrays fabricated by e‐beam annealing of ion‐implanted layers show an edge resolution of 40 μm between unannealed and annealed regions. The diodes have characteristics close to those predicted for ideal structures and may be fabricated in arrays to make integrated devices such as vidicon targets.

Fabrication and performance of ferrite phase shifters for millimeter frequencies

Abstract: Ferrite devices for millimeter frequencies, 35 GHz to 94 GHz, are difficult to fabricate and have marginal performance. This paper discusses the design and arc plasma fabrication process for non-reciprocal ferrite phase shifters for millimeter frequencies. Design and fabrication techniques were developed for 35 GHz, prior to the initial fabrication of 94 GHz phase shifters. A lithium ferrite powder with a 4100 Gauss (4πM s ) was used for arc plasma spraying the phase shifters, The treatment of the ferrite powder and its arc plasma spray characteristics are discussed. Device performance was evaluated with respect to insertion loss, bandwidth, and differential phase shift. Any imperfections in the fabrication of the ferrite phase shifters, such as cracks or poor ferrite dielectric fit, adversely affect their performance. Phase shifter design variations included: dielectric loading, placement of the switching wire, phase shifter height, and metalization techniques. Based on this work, it was possible to design and fabricate ferrite phase shifters with good performance at millimeter frequencies.

Fabrication of silicon oxynitride masks for x‐ray lithography

Abstract: The fabrication of optically transparent silicon oxynitride x‐ray masks using CVD process on silicon is reported in this paper. The etch rate in the ethylenediamine, pyrocatechol, and water mixture used for substrate removal has shown a strong dependence on the layer composition. Because of the notable etch rate of SixOyNz films, it is of advantage to cover them with a thin (?500 A) Si3N4 layer. Thin Si3N4/SixOyNz/Si3N4 composite membrane foils have been fabricated with a total thickness of 6000 A and a window size of 2.5×2.5 cm2. Fizeau interference measurements showed that the window geometry has a significant influence on the total geometrical distortion of the thin mask membrane.

Wall element comprising a solar collector which is disposed between two transparent panes

Abstract: A wall element, comprising a solar collector which is arranged between two panes and which comprises a number of rotatable absorber plates One side of the absorber plates is provided with a non-selective black coating and the other side is provided with a selective, heat-reflective layer The absorber plates are accommodated in evacuated, transparent tubes

Fabrication of optical waveguide taper couplers utilizing SiO 2

Abstract: The fabrication of optical waveguide couplers involving tapered layers of is discussed. Details of the SiO2 photolithographic fabrication processing sequence are presented. This process utilizes carefully controlled etchant undercutting and has been found to be quite reproducible. It has allowed fabrication of tapers having changes in SiO2 thickness of 1.0 μm over lengths of 55–75 μm. Results are presented which demonstrate taper transverse uniformity for distances of over 600 μm. The smoothness and gradual nature of the tapers are apparent in scanning electron microscope pictures of a taper cross section.

The fabrication of Schottky-barrier solar cells by electroless nickel plating

Abstract: Fabrication of Schottky‐barrier solar cells by electroless nickel plating can be recognized as a practical approach because cells made by this method are of lower cost, have good adhesion to the surface, higher barrier potential height, and lower reflectivity of light as compared with those of the vacuum‐evaporated devices. No expensive equipment, such as a vacuum evaporator or high‐temperature diffusion oven, is needed for this manufacture.

Fabrication of 8 turn multi-track thin film heads

Abstract: To obtain high bit and high track densities, fabrication of thin film magnetic recording heads has been studied by a number of companies.) This paper describes a newly developed method for fabricating layered type, multi-turn, multi-track thin film inductive heads with a central tap by using photolithographic and thin film deposition techniques.

Optical fiber fabrication method and apparatus

Abstract: An optical fiber fabrication method and apparatus are described which are capable of producing reproducible and uniform layers of fiber quality glass. The formation of a saturated stream of glass precursor vapor by condensation allows for the delivery of calibrated predetermined quantities of vapor to an appropriate fiber fabrication apparatus, thereby permitting improved fabrication characteristics.

Microelectronic fabrication method minimizing threshold voltage variation

Abstract: A microelectronic fabrication process for minimizing the threshold voltage variation across the surface of a wafer of semiconductor material. The process precisely specifies the degenerate (or heavily doped) impurity profile distribution by using ion implantation so as to minimize the autodoping of adjacent gate regions immediately after the ion implantation step during gate oxidation, while maximizing the surface concentration of the dopant at the ultimate silicon surface to achieve appropriate surface sheet resistance and junction depth after all circuit fabrication steps have been completed.

Fabrication of palladium anode for X-ray lithography

Abstract: A fabrication process for making palladium-plated target anodes for X-ray lithographic systems is characterized by a unique sequence of surface preparation, plating and annealing steps. Anodes made by the process have been operated reliably at high-power levels for extended periods of time.

Reversal Etching of Chromium Film in Gas Plasma

Abstract: The mechanism of the reaction in the reversal gas plasma etching of anti‐reflective chromium photomasks was studied. Auger spectrometer and x‐ray photoelectron spectrometer studies of the film revealed that is incorporated in the surface of the chromium oxide layer of the anti‐reflective photomasks for the samples showing reversal etching. forms a kind of masking layer for the etching. Decomposed species of the photoresist film are found to be responsible for the etching of , and carbon monoxide is proposed as the reactive species for etching the masking layer. This reversal etching was applied to the fabrication of the photomasks for MOS LSI.