Rockwell International Corporation

Other

Hughes Aircraft Company

James J Licari

Thomas Wright

Aram A Tanielian

Lorren Stiles

Gabriel G Bakhit

Robert Willing

Dale W Swanson

Howard P Harper

Robert C Kass

Bruce E Hamilton

Theodore J LaChapelle, Jr

Deborah J Smith

Robert E Spero

John R Davis

Seepage of water and other impurities into hermetically sealed on plastic encapsulated modules leads to eventual device failure, as conductor material corrodes and opens, or electromigrates to establish conductive trails across a substrate, shorting the conductors. To forewarn of such failure, a sensing device defined as a separate chip is packaged in the same module with the circuit to be checked, with pinouts that can be tested with a circuit that is usually external. The sensor makes use of the moisture-induced migratory behavior that causes the problem, using a highly migratory metal or alloy to define paired electrodes spaced as closely as 2 micrometers apart. The metal of the electrodes undergoes rapid ionization and migration in the presence of trace amounts of moisture, dissolved ionic contaminants, and a small potential difference across the electrodes. Two volts applied to the sensor conductors by the sensor circuit will output a voltage if even a minute current is flowing between the electrodes permitting 'go/no-go' decisions to be made regarding use of the module. The moisture which actuates the sensor, triggers the circuit long before the level of seepage and electromigratic represents present danger of circuit failure, and long before other types of sensors would indicate the existence of a problem.

Moisture sensor for electronic modules

A High-Density-Multi-Chip (HDMI) substrate structure (10) includes alternating conductor metallization (24,28,36,54,56) and insulating dielectric layers (14,38). The dielectric layers (14,38) are formed by curtain coating of ultraviolet photoimageable epoxy material, and the metallization (24,28,36,54,56) is formed by electroless plating or sputtering of copper. The dielectric layers (14,38) are photoimaged and developed to form via holes (16,40,44), and vias (18,42,46) are formed in the holes (16,40,44) by electroless copper plating. The metallization (24,28,36,54,56) can be formed in the same manner as the dielectric layers (14,38), or can alternatively be formed by subtractive photolithography using photoresist masks.

Microelectronic circuit substrate structure including photoimageable

Images are provided to a pilot in an aircraft overflying the earth by means of a helmet mounted display system. The position and attitude of the aircraft with respect to the earth and the attitude of the helmet with respect to the aircraft are monitored in order to convert a plurality of stored earth position signals into helmet coordinates. Earth points which are viewable by the pilot are displayed using symbolic images thereof such that the symbolic images coincide, from the pilot's point of view, with the actual positions of the viewable points on the earth.

Contact-analog headup display method and apparatus

A microelectronic device is rendered resistant to reverse engineering by encapsulating it in a dual layer encapsulant. The inner layer is compatible with the operation of the device, and has a greater resistance to chemical attack then does the device. The outer layer includes a filler of barium sulfate and gadolinium oxide, to absorb X-rays and N-rays respectively, is more resistant to chemical attack than the inner layer, and includes a groove around its periphery, to preferentially allow chemical attack radially. A full chemical attack damages the device beyond usable inspection, but a partial chemical attack is insufficient to remove X-ray and N-ray concealment.

Reverse-engineering resistant encapsulant for microelectric device

An adhesive mixture reworkably adheres electronic integrated circuit dies to hybrid microcircuit substrates, and includes a thermosetting epoxy resin. A thermoplastic resin additive allows the mixture to retain the high adhesive strength of the epoxy resin up to approximately 150.degree. C., or the upper limit of the operating and testing temperature range of the dies, and then soften sufficiently to enable defective dies to be removed at a temperature of preferably between 150.degree. C. and 200.degree. C. without damage to the substrate or adjacent dies.

Reworkable epoxy die-attach adhesive

A monometallic batch process for forming beam leads of a preferred metal such as aluminum or gold. The process is applied to a wafer of finished microelectronic devices already having metal contact pads of the same preferred metal. Where aluminum is the desired metal, high deposition rates are used to minimize aluminum oxide contamination. High yield is achieved by forming the beam leads to have an elevated cantilevered configuration, by deep scribing of the wafer and, when desired, by providing an energy absorbing cushion to reduce the effect of collisions between chip edges and beam leads.

Batch process providing beam leads for microelectronic devices having

A composition for forming a boundary lubricant for metal and ceramic wear surfaces consisting of transition element complexes, including those of the higher molecular weight carboxylic acids such as the long chain fatty acids (C.sub.x H.sub.2x.sub.+1 COOH; x = 8, 9, 10, . . . 29). The transition elements used here are metals such as Cr, Mn, Fe, Co, Ni or Al that can form coordination complexes. Exemplary metal complexes are chromium stearate and chromium behenate. An exemplary complex may be prepared by (1) reducing chromium trioxide by a reducing alcohol in a low molecular weight organic acid to produce chromium acetate; then 2 hydrating and olating the chromium acetate. A solution containing a maximum concentration of about 11 weight percent of the transition metal complex in a solvent such as trichloroethylene is applied as a thin layer onto a wear surface, then the layer is heated for 1-4 hours at a temperature at or above 70.degree.C and, within the approximate range 70.degree.-160.degree.C. The transition metal complex chemically adheres to the wear surface, and is cross-linked by the heat treatment, to form an anchored, polymerized array of molecules that provides a hydrophobic, durable, boundary lubricant having a low coefficient of friction. The transition metal complex solution may be applied to non-porous wear surfaces or, alternatively, may be impregnated into chrome oxide coatings or other porous refractory coatings on wear surfaces to form a porosity-filling boundary lubricant thereon. The lubricant decreases the clearance required between porous bearing surfaces, decreases the formation of corrosion cells, and lowers the coefficient of friction. The preferred amount of fatty acid or organic polyacid that can be stably incorporated into a complex chromium soap for use as a porosity-filling lubricant, that is, the optimum fatty acid mol/chromium gm-atom ratio, is approximately 1-1.2/1.

Growing community of inventors

Whittier, CA, United States of America

James J Licari