Abstract: An IGFET ROM is programmed later in its process of manufacture. An array of IGFETs having an operable channel region and gate electrode is provided. The gate electrode is penetrable by an ion beam. A first dielectric penetrable by the ion beam is deposited onto the array. A second dielectric not penetrable by the ion beam is then deposited onto the array. Windows are then etched into the second dielectric material but not the first, over channel regions of selected IGFETs. The wafer surface is given an ion implantation to change threshold voltage of those IGFETs selected. A metallization pattern is formed on the second dielectric, with the first dielectric providing an insulating coating for gate electrode portions otherwise exposed within the aforementioned windows.

Abstract: A method of making a highly porous cermet electrode on a solid electrolyte. The solid electrolyte is coated with noble metal and glass particles and heated to fuse the glass particles. The coated electrolyte is then annealed to form a separately leachable borate phase in the glass. That phase is then leached from the coating to leave a highly porous silica matrix throughout which the conductive particles are exposed.

Abstract: A titanium oxide resistive-type exhaust gas oxygen sensor having a unique microstructure of interlocked highly irregular, flake-like particles forming a highly durable porous body preferably having a surface area greater than about 3 square meters per gram. A method for producing such particles and forming them into such a high surface area body is also described.

Abstract: An inexpensive method for making a durable porous overcoat on a noble metal exhaust electrode of a solid electrolyte exhaust gas oxygen sensor. The electrode is coated with aluminum flakes and the aluminum flakes oxidized in situ by heating in an oxidizing atmosphere.

Abstract: A reference electrode is rapidly automatically applied to the interior of tapered vitrified zirconia thimbles for an exhaust gas oxygen sensor. The coating is consistently smooth and predetermined in physical and electrical characteristics. In a specific example, a hollow elastomeric finger is nested within the thimble after dispensing a measured quantity of conductive ink into the thimble bottom. A gas jet applied to the ink from the finger lower end flows the conductive ink throughout a coating cavity below a shoulder in the finger after the ink quantity is substantially all applied to cavity walls, it no longer blocks a cavity vent, and allows the gas to flow freely through the cavity. Gas flow is then discontinued, and the finger withdrawn from the thimble.

Abstract: A method of sputtering platinum onto a vitrified zirconia thimble to form an exhaust electrode for an electrochemical-type exhaust gas oxygen sensor. The electrode is sputtered under an atmosphere consisting essentially of more than about 50% oxygen and/or nitrogen by volume. Sensors having low symmetrical transition times are produced.

Abstract: In a preferred embodiment of the invention, a method of making a solid electrolyte electrochemical-type exhaust gas oxygen sensor. A platinum exhaust electrode is sputtered onto a zirconia body and the body then heated in nitrogen at 700.degree.-900.degree. C. for at least 30 minutes to reduce rich-to-lean switching time response.

Abstract: A titanium oxide resistive-type exhaust gas oxygen sensor having a unique microstructure of interlocked highly irregular, flake-like particles forming a highly durable porous body preferably having a surface area greater than about 3 square meters per gram. A method for producing such particles and forming them into such a high surface area body is also described.

Abstract: A method of sputtering a platinum exhaust gas electrode onto a vitrified zirconia thimble for an electrochemical-type exhaust gas oxygen sensor. Porous high surface area platinum films are deposited that have more consistent properties. A platinum target is spaced about 3.0-4.5 cm from the thimble and more than 6 cm from the sputtering anode. A pressure of about 10-20 millitorr is used during sputtering at a DC power of about 13-22 watts/cm.sup.2 of target area.

Abstract: A thermistor composition containing zinc oxide, manganese oxide, and cobalt oxide in selected ternary ratios together with small portions of titanium oxide. The titanium oxide addition to the selected ternary ratios of the other three oxides provides a more constant temperature coefficient (beta) over a range of about 300.degree. F. that includes room temperature.

Abstract: A readily manufacturable heated solid electrolyte oxygen sensor. The sensor includes a generally planar heater supported on a tubular reference electrode terminal in desired position normal to the longitudinal axis of said terminal and parallel to a generally planar solid electrolyte member within a cylindrical housing. The heater and terminal form a subassembly readily assemblable in concentric relationship with the planar solid electrolyte member and the cylindrical housing.

Abstract: A power semiconductor device package is made using a subassembly of a die mount substrate and a lead frame. The subassembly is interlocked in a manner that permits relative movement without losing alignment. A method is described in which the lead frame interlock has a first position to facilitate making electrical interconnections. In a second position, package encapsulation is facilitated. In a preferred embodiment the lead frame interlocks with an element lightly press fitted in package mount holes in the die mount substrate. After package encapsulation, the interlock element is pressed out of the substrate to separate unused parts of the lead frame from the package and to make the substrate holes available for package mount.

Abstract: A galvanic exhaust gas sensor having a solid electrolyte disc having a porous electrode thereon for detecting oxygen partial pressure in an exhaust gas stream varying in its flow and composition and having a shield protecting the porous electrode from direct impingement of exhaust gas stream. The shield includes means for accelerating exhaust gas from across the disc face at exhaust gas stream velocities and pressures below a preselected level and for maintaining said flow more constant at exhaust gas stream velocities and pressures above the preselected level, effective to more accurately sense variations in oxygen content of the exhaust gas stream at a porous electrode.

Abstract: A readily manufacturable heated solid electrolyte oxygen responsive exhaust gas sensor. An elongated heater is insulatingly supported in subassembly with a tubular reference electrode terminal in desired predetermined disposition relative to the solid electrolyte. The heater has an enlargement intermediate its ends. The heater is coaxially nested within a pair of ceramic sleeves, with the sleeves axially spaced by the enlargement. The sleeves are in turn coaxially disposed within the electrode terminal, and clamped together by inward electrode terminal shoulders, one of which is preferably formed by crimping. The heater enlargement is preferably integrally formed. No special inlet need be provided in the sensor for admission of air when air reference is used.

Abstract: A solid electrolyte exhaust gas oxygen responsive sensor having a platinum exhaust gas electrode and a porous ceramic coating on the electrode. The porous ceramic coating contains rhodium for making the sensor also responsive to NO.sub.x. In a specific example, rhodium permeates a gamma alumina porous overcoat on a sputtered platinum film serving as an exhaust gas electrode on a zirconia solid electrolyte member.

Abstract: A stripper for removing a photoresist mask. The stripper consists essentially, by volume, of about 50-85% tetrachloroethylene and ortho-dichlorobenzene in generally equal amounts, about 15-50% dodecylsulfonic acid, and up to 3% formic acid.

Abstract: A semiconductor diode laser tunable within a range of over 200 wave numbers. Increased tuning range of a lead-salt laser, from about 30 to over 200 wave numbers, is attained by providing an increasing majority carrier concentration in the laser crystal within the laser cavity in the direction extending away from the contiguous PN junction contiguous the laser cavity.

Abstract: A readily manufacturable heated solid electrolyte oxygen sensor. The sensor includes an elongated heater supported on a tubular reference electrode terminal in desired position relative to a solid electrolyte member within a cylindrical housing. The heater and terminal form a mutually electrically isolated subassembly in which the heater is in predetermined disposition with respect to the solid electrolyte member. An elongated heater is disposed within one or more ceramic sleeves that are in turn disposed within the electrode terminal tube. The heater, sleeves, and the terminal tube are vitreously bonded together to form a subassembly.

Abstract: A readily manufacturable heated solid electrolyte oxygen sensor. The sensor includes a heater supported on a tubular reference electrode terminal in desired position relative to a solid electrolyte member within a cylindrical housing. The heater and terminal are constructed as a subassembly readily assemblable in concentric relationship with the solid electrolyte member and the housing.

Abstract: A readily manufacturable heated solid electrolyte oxygen sensor having an elongated heater supported in subassembly with a tubular terminal for a reference electrode of the sensor. The heater is coaxial with the electrode terminal for predetermined disposition with respect to the sensor solid electrolyte member. The heater includes a rod coaxially in a ceramic tube and a resistance heating coil and crimped outer connector around the ceramic tube. Fused glass, directly bonded to the ceramic tube, supports the heater in the electrode terminal.