摘要:
A method for forming a ruthenium-based thick-film resistor having copper terminations, in which the thick-film resistor is fired in a non-oxidizing atmosphere so as not to oxidize the copper terminations yet without reducing the thick-film resistor to metallic ruthenium. A ruthenium-based thick-film resistor ink having a matrix material and an organic vehicle is deposited on a copper layer that will form the terminations for the thick-film resistor formed by firing the ink. The organic vehicle of the ink is then burned out at a temperature of less than 350° C. in an oxidizing atmosphere, such as air. Thereafter, the ink is fired in a non-oxidizing atmosphere (e.g., nitrogen) at a temperature sufficient to sinter the matrix material and yield a ruthenium-based thick-film resistor with copper terminations formed by the copper layer.
摘要:
A process for forming stable integrated resistors (14) and capacitors (28) on organic substrates (12). The resistors (14) and capacitors (28) are capable of a wide range of resistance and capacitance values, yet can be processed in a manner that does not detrimentally effect the organic substrate (12) or entail complicated processing. The method generally entails the use of thick-film materials usually of the types used to form resistors and capacitors on ceramic substrates. The thick-film materials are applied to an electrically-conductive foil (20) and then heated to bond the thick-film material to the foil (20) and form a solid resistive or capacitive mass (16/30). The foil (20) is then laminated to an organic substrate (12), such that the resistive/capacitive mass (16/30) is attached to and preferably embedded in the organic substrate (12). Finally, the foil (20) is etched to form at least one of two terminals that contact the resistive/capacitive mass (16/30) and thereby complete the passive electrical component (14/28). Resistors (14) can also be formed of polymer thick-film (PTF) inks, in which case the PTF ink is cured on the foil (20) for an extended period at a temperature sufficient to completely cure the ink prior to laminating the foil (20) to the organic substrate (12).
摘要:
A hybrid circuit structure that includes a metal substrate, an inorganic electrical insulator layer and at least one inorganic thick-film passive circuit element, such as a thick-film resistor, capacitor or conductor. An interface layer is provided between the insulator layer and the circuit element to prevent the detrimental effects of interlayer diffusion. The composition of the interface layer is selected to prevent the diffusion of constituents from the inorganic insulator layer, and to have a CTE near that of the circuit element to reduce thermal fatigue. As a result, the passive circuit element can be formed of essentially any one of a number of conventional inorganic thick-film materials that are widely used on alumina substrates.
摘要:
A sensor (10) having polysilicon strain-sensing elements (20) on a metal diaphragm (16). A thick-film insulating layer (18) covers the metal diaphragm (16), and thin-film polysilicon resistive elements (20) are formed on the thick-film insulating layer (18). Thick-film conductors (22) are formed on the thick-film insulating layer (18) and contact the thin-film polysilicon resistive elements (20) to form electrical interconnects to the resistive elements (20). The thick-film conductors (22) preferably contain silicon in order to reduce diffusion of silicon from the polysilicon resistive elements (20). The thick-film insulating layer (18) may be made up of a number of individual thick-film layers, the uppermost of which is stable and nonreactive with the thin-film polysilicon resistive elements (20) and the thick-film conductors (22) at temperatures of at least 600.degree. C. A passivation layer (24) overlies the thin-film polysilicon resistive elements (20) and the thick-film conductors (22). The sensor (10) can be made sufficiently rugged to be used as a structural member of a fluid-containing vessel.
摘要:
A high temperature thick-film hybrid circuit is characterized by a surface-mount circuit component that is electrically interconnected with a conductor. The surface-mount circuit component of the thick-film hybrid circuit is bonded to the conductor with a soldering technique employing dual-solder layers. The dual-solder layers enable component attachment to the conductor at a temperature below the maximum processing temperature of the component, while forming a solder joint that exhibits suitable adhesion properties at temperatures in excess of 165.degree. C. The dual-solder layers can be chosen to inhibit tin diffusion from the solder, silver leaching from the conductor, and the formation of a brittle intermetallic at the solder-conductor interface.
摘要:
A cost effective method is provided for determining empty and/or near empty medical and other medical emergency oxygen tanks employing a single, simple device for practicing the method, comprised of 5 or 6 readily obtainable components, to issue visual and audible alarms when the oxygen pressure of a medical oxygen tank has decreased to a predetermined pressure, deemed too low to provide the needed and/or prescribed oxygen flow rate to a patient to alert medical personnel and other caregivers that it is time to replace the tank in with a full tank.
摘要:
A thick-film strain-sensing structure for a media-compatible, high-pressure sensor. The strain-sensing structure generally includes a metal diaphragm, at least one electrical-insulating layer on the diaphragm, an interface layer on the electrical-insulating layer, and at least one thick-film piezoresistor on the interface layer for sensing deflection of the diaphragm. The interface layer and the electrical-insulating layers are preferably formed by thick-film processing, as done for the piezoresistors. For compatibility with the metal diaphragm, the electrical-insulating layer has a CTE near that of the diaphragm. The interface layer is formulated to inhibit and control diffusion of the electrical-insulating layers into the piezoresistors. For this purpose, the interface layer is formed from a composition that contains, in addition to a suitable organic media, alumina, zinc oxide, and at least one glass frit mixture comprising lead oxide, a source of boron oxide such as boric acid, silica and alumina. Additional constituents of the interface layer preferably include titania, cupric oxide, manganese carbonate as a source for manganese monoxide, and cobalt carbonate as a source of cobalt oxide.
摘要:
A method of six (6) weeks duration for increasing body fitness level while reducing health risks, reducing inches of girth for body parts and losing body weight is provided. The method is comprised of three steps: (1) Body Cleansing, (2) Muscle Toning and Strengthening, and (3) Body Balancing. Each step is of two weeks duration and is comprised of a specific eating plan (in the case of step 1 includes a water intake regimen) and a specific exercise plan. The eating plan and exercise plan of each step is specifically formulated to provide upon completion of the six (6) weeks significant weight loss, lower BMI and reduced body part girth.
摘要:
16 A thick-film circuit (10) includes an electrically conductive substrate (12), such as stainless steel, and a first layer of a gold-rich conductor (15) applied directly thereon. The gold layer is fired in a non-oxidizing atmosphere, such as nitrogen, to ensure a solid mechanical and electrical connection between the gold and the substrate. A next layer of a silver composition (20) containing a first proportion of silver to a conductive metal is directly applied to the gold layer (15). Preferably, the composition (20) includes palladium in equal parts with the silver to achieve a secure mechanical and electrical contact with the gold layer with a minimum resistivity. A silver-rich layer (23) is then applied directly onto the intermediate layer. This silver-rich layer (23) is a composition of silver and the conductive metal in a second proportion greater than the first proportion. In one embodiment, this second proportion is three parts silver to one part palladium by weight. The thick-film stack-up (10) provides a minimum resistance conductive path between electrical components mounted on the silver-rich layer (23) and the conductive substrate (12).