Abstract: Optically nonlinear device elements such as directional couplers, switches, frequency stabilizers, optical parameters devices and modulators use as an optically nonlinear element a cross-linked triazine polymer containing a covalently bonded optically nonlinear dye moiety. A specific cross-linked triazine with this dye moiety may be made by cyclotrimerizing a p-(N,N-bis(4'-cyanatobenzyl)amino-p'-(2,2-dicyanovinyl)azobenzene monomer. During polycyclotrimerization or cure, the element is subjected to a poling voltage which aligns the dipoles of the dye moiety to give a large useful nonlinear susceptibility.

Abstract: A fluorine-doped silica soot cylinder (11) is consolidated by containing it within an encapsulation structure (29) within a furance (21). The atmosphere within the encapsulation structure is kept substantially stagnant during the consolidating, and the volume enclosed by the encapsulation structure (29) is only slightly greater than the volume of the soot cylinder (11). A gap (52) between the volume enclosed by the encapsulating structure and the furnace is kept small enough to impede gas flow to a sufficient extent that the atmosphere within the encapsulating structure (29) is substantially stagnant during consolidation. During consolidation, fluorine concentration within the encapsulation structure (29) is uniformly distributed within the soot cylinder (11).

Abstract: A semiconductor wafer 11 is mounted on an elongated member 18, one end of which is rotatable about a transverse axis (14), thereby to distribute a liquid on the upper surface of the wafer more evenly. In order to stabilize the rotation of the elongated member, a second elongated member is preferably attached end-to-end to the elongated member (18) and rotates with it. A counterweight (26) in the second elongated member moves during the rotation such that the distance between the wafer and the central axis and the distance between the center of the counterweight and the axis are substantially equal. The weight distribution is approximately symmetrical about the axis and the structure is dynamically stabilized. The counterweight and the wafer assembly may be moved during rotation by applying air pressure from the source (23) to pistons (13,26) in the two elongated members.

Abstract: A laser (24) is mounted in predetermined alignment with a monocrystalline mounting member (11) by defining in the mounting member a reference surface (18) that is displaced from a second surface (19). Solder (29) is placed on a second surface such that in its solid form its length and width each significantly exceeds its height. The laser is bonded to the reference surface such that part of the laser overlies the solder and is separated from the solder by a small gap (30). Next, the solder is melted to cause it to gather on the second surface sufficiently to contact an under surface (31) of the laser. The solder is then cooled such that the solder bonds the laser to the silicon mounting member.

Abstract: An electronic device (10) is surface mounted to bonding pads (11) of a substrate (12) by first mounting the device within an aperture (24) of a glass plate (17). The leads (14) of the electronic device are coated with solder and pressed onto the bonding pads by the reusable glass plate (17). While pressing the plate against the leads, the plate is scanned with a laser beam (16) directly over each row of bonding pads. The laser light is of an appropriate wavelength such that the glass plate converts the laser light to heat, which melts the solder to bond the leads to the bonding pads.

Abstract: Efficient coupling between an optoelectronic device (13) and an optical fiber (15) is obtained by using different monocrystalline elements of different crystallographic orientation for mounting, respectively, the fiber and the optoelectronic device. For example, the crystallographic orientation of an upper monocrystalline element (17) is chosen such that a horizontal groove (20) for supporting the optical fiber and a reflecting surface (19) for directing light into the fiber may both be made by anisotropic etching. The crystallographic orientation of a lower monocrystalline silicon element is chosen such that appropriate etching will yield a mounting surface (23) for the optoelectronic device (13) which is suitable for directing light from the reflecting surface (19) into the optical fiber (15) with maximum efficiency.In one illustrative embodiment, the upper monocrystalline element (17) is {100} silicon, and the lower monocrystalline element (18) is {112} silicon.

Abstract: In a radio-frequency plasma deposition reactor (10), SiO.sub.2 is deposited from a source (16) of tetraethoxysilane (TEOS). The deposition is made to be anisotropic, that is, to be deposited preferentially on horizontal surfaces, by use in the deposition atmosphere of a constituency such as NH.sub.3 or NF.sub.3 which inhibits SiO.sub.2 deposition, along with a radio-frequency power in excess of 100 watts, which preferentially removes the inhibiting gas from horizontal surfaces through ion impact.

Abstract: An ohmic contact to III-V semiconductor material comprises substantially eighty to ninety-five percent by weight of tungsten, five to ten percent by weight of antimony, and zero to fifteen percent by weight of indium. The materials are simultaneously sputtered from separate targets in a sputtering reactor.

Abstract: The purpose of the invention is to detect impurities in a semiconductor wafer (20). A laser (21) forms a light beam having a high proportion of its power at an optical frequency capable of being absorbed by the impurity to be measured. The beam is split into first (25) and second (26) light components, one of which is directed at the surface of the semiconductor wafer (20) to be tested and the other at a reference semiconductor wafer (27) containing a known quantity of the impurity to be measured. The light intensities reflected from the two wafers is detected by photodetectors (29, 30) and their difference is taken as a factor in measuring the impurity density in the wafer under test. A polarizer (33) polarizes the beam such as to maximize p-type component and minimize s-type components. Reflection from each of the two wafers (20, 27) is at the principal angle.

Abstract: A reagent chemical is directed along a first pipe portion (20) that extends along one side of the array of wafers (14) and which contains a plurality of jets (33) for projecting the chemical toward the wafers. A plurality of second pipe portions (21) transmits an inert gas, with each pipe portion having a plurality of jets (34) for projecting the gas toward the floor of the tank.

Abstract: An electronic device package is made by first making in a stencil member (11) an opening (12) in the shape of a closed loop that surrounds an inner portion (13) of the stencil member. The closed loop is a continuous opening except for a plurality of web members (15), each of which extends across the opening to secure the inner stencil portion to the remainder of the stencil member. A glass slurry (7) is forced through the opening of the stencil member onto a first substrate (18) so as to form on the substrate a substantially closed loop of glass slurry, which is thereafter glazed to form a glass loop (32) bonded to the first substrate. The first substrate is used as cover plate and placed over a second substrate (24) containing an electronic device (23) such that the glass loop surrounds the electronic device and contacts the second substrate along its entire length. The glass is heated sufficiently to soften it and cause it to bond to the second substrate as well as the first substrate.

Abstract: The specification describes a process for making a plating mask (17), for use in printed wiring board fabrication, with greater precision and definition than has previously been possible. An insulative substrate (11) includes on one surface a thin metal film (13). The film is covered with a relatively thick first mask layer (16) which is selectively removed to expose portions of the metal film, which are in turn removed to expose portions of the insulative substrate (11). The exposed portions of the insulative substrate are covered with a relatively thick plating mask layer (17) which abuts against the first mask layer (16). The first mask layer is then removed, leaving the remaining plating mask layer as a patterned plating mask which is then used as a mask for deposited metal (19) which defines a printed circuit.

Abstract: A laser (20) directs a laser beam at an optical fiber (12) and the resulting forward-scattered light is detected by a detector (21). The energy of the foward-scattered laser light is monotonically inversely proportional to the thickness of a carbon coating on the optical fiber. A computer (22) generates an electrical signal for controlling carbon coating thickness by driving a valve (24) to control the flow of acetylene from a source (14) used to coat the optical fiber in a coating chamber (13).

Abstract: In a process for repairing electronic device packages, the problem of removing solder remnants on substrate bonding pads is solved by, first, etching a pattern in silicon and metallizing the pattern to make a silicon wick. The solder remnants on the bonding pads are melted, and the etched pattern of the silicon wick is brought into contact with the remnants to remove them by capillary action. It is often convenient to heat the silicon wick so that solder remnants melt when the wick is brought into contact with them.

Abstract: In a vertical gradient freeze (VGF) process for growing a large crystal of a Group III-V compound semiconductor in a pyrolytic boron nitride crucible (11), a major part of the inner surface of the crucible is first oxidized to form a boric oxide layer (12).

Abstract: A lightguide preform is fabricated by depositing a thin carbon layer (40) on a cylindrical glass mandrel (30) and further depositing a plurality of glassy soot layers (32) thereover. The resulting composite structure is heated, in a furnace, at a low temperature to remove the carbon layer (40) and then heated at an elevated temperature to consolidate the glassy soot layers on the glass mandrel to form the lightguide preform.

Abstract: In IC fabrication, feature size accuracy is monitored by making a test pattern composed of grating lines in proximity to two reference patterns. With the proper feature size, the test pattern will visually appear to have a shade of grey intermediate that of the two reference patterns. Too small a feature size will make the test pattern lighter, while too large a feature size will make it appear darker.

Abstract: A capacitor in parallel with a CMOS memory is used, in the event of a power outage, to apply a sufficient temporary voltage to the memory to maintain the stored data. Data storage retention time is maximized by a resistor, connected between the capacitor and the memory, having a resistance R approximately given byR = 0.4 (V.sub.i - V.sub.f)/I.sub.f (1)where V.sub.i is the initial voltage on the capacitor, V.sub.f is the minimum voltage for maintaining the data and I.sub.f is the capacitor discharge current at voltage V.sub.f.

Abstract: Integrated circuit mask patterns are laser machined by mounting substrates on a support that is periodically stepped in a y direction after each scan by a laser writing beam in an x direction. X-direction scanning is accomplished by mounting a mirror on a carriage that reciprocates by rebounding between two displaced coil springs. A coding laser beam is reflected from the carriage through a stationary code plate, comprising alternate transparent and opaque stripes, to monitor the position of the carriage and to control the modulation of the writing beam.

Abstract: A Schottky barrier contact includes a thin layer of high carrier concentration impurities ion implanted over the contact surface of the semiconductor. This reduces the electronic barrier height, increases the tunneling component, and thus reduces the forward-bias turn-on voltage of the diode. The implanted layer has a carrier concentration at least ten times that of the semiconductor substrate, and a thickness smaller than the width of the inherent depletion region resulting from the internally generated electric field at the metal-semiconductor interface. An implanted layer of the opposite conductivity type raises the barrier height.