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Showing papers on "Barrier layer published in 1969"


Journal ArticleDOI
TL;DR: In this paper, anodic barrier layer oxide was observed with a boric acid electrolyte maintained at 60°C and two film layers were observed: the uppermost layer being extremely thin and the secondary phase barrier layer being on the order of 200Aa.
Abstract: Direct observations of anodic barrier layer oxide, by transmission electron microscopy, provide further evidence for the duplex film structuring suggested earlier, based on infrared data. Anodic films were prepared with a boric acid electrolyte maintained at 60°C and two film layers were observed: the uppermost layer being extremely thin. Only the layer lying next to the metal (primary phase barrier layer) showed a thickness relationship with respect to forming voltage: 14.8 Aa/v. The thickness of the uppermost layer (secondary phase barrier layer) was on the order of 200Aa and was essentially independent of forming voltage. With the boric acid electrolyte employed at 90° C, a pronounced increase was found in the thickness of the uppermost layer. The thickness of the layer next to the metal surface remained consistent with the ~14 Aa/v relationship. Infrared, coating weight, effluent gas detection, and impedance data were also obtained for these coatings and correlated with the data obtained by transmission electron microscopy.

32 citations


Patent
22 Jul 1969
TL;DR: In this article, the authors describe an "anisotropic ULTRA-filtration MEMBRANE COMPRISING a POROUS Support LAYER, a LESS PORous Barrierer LAYer, and an ADHERING COATING of IRREVERSIBLY COMPRESSED GEL, when in CONTACT with a FLOWING LIQUID at a LIquid SHEAR RATE of about 16000 SEC.-1; and METHOD for making SAME.
Abstract: AN ANISTROPIC ULTRAFILTRATION MEMBRANE COMPRISING A POROUS SUPPORT LAYER, A LESS POROUS BARRIER LAYER INTEGRAL THEREWITH, AND AN ADHERING COATING OF IRREVERSIBLY COMPRESSED GEL, SAID COATING ADHERING TO SAID MEMBRANE WHEN IN CONTACT WITH A FLOWING LIQUID AT A LIQUID SHEAR RATE OF ABOUT 16000 SEC.-1; AND METHOD FOR MAKING SAME.

29 citations


Patent
12 Nov 1969
TL;DR: In this paper, a preselected barrier layer, such as nickel, which functions to prevent the penetration of subsequently applied process materials such as solder, which might adversely affect the underlying gold layer, is deposited on the gold layer.
Abstract: An ohmic contact system for a ceramic body having a predetermined relationship between various physical characteristics, such as temperature and resistance, for example, a wafer of semiconducting barium titanate having a positive temperature coefficient of resistance. A film of germanium is deposited on at least one surface of the wafer to protect the surface properties thereof. A layer of a preselected metal which adheres well to germanium and is readily bondable, such as gold, is deposited on the germanium film. A layer of a preselected barrier layer, such as nickel, which functions to prevent the penetration of subsequently applied process materials, such as solder, which might adversely affect the underlying gold layer, is deposited on the gold layer. An exterior layer of a readily solderable material which adheres well to the underlying nickel layer, such as gold, is deposited on the nickel layer. An external electrical conductor may then be readily soldered to the external gold layer to provide a good ohmic and mechanical contact to the wafer. An additional base layer of a preselected material, such as palladium, which adheres well to nickel and to gold may be deposited intermediate the nickel layer and the exterior gold layer to provide an improved base for the external gold layer.

22 citations


Patent
14 Feb 1969
TL;DR: In this paper, the authors present a means and method for rendering solderable a stainless steel body resistant to corrosive attack from common electrolytes, which includes the steps of covering at least one surface of a steel body with layers of metal including a first metal layer selected from the group consisting of nickel, cobalt and chromium which serves as a barrier layer to the diffusion of a subsequent metal layer or layers therethrough to the stainless steel.
Abstract: Means and method for rendering solderable a stainless steel body resistant to corrosive attack from common electrolytes. The method includes the steps of covering at least one surface of a stainless steel body with layers of metal including a first metal layer selected from the group consisting of nickel, cobalt and chromium which serves as a barrier layer to the diffusion of a subsequent metal layer or layers therethrough to the stainless steel body. The subsequent metal layer is resistant to corrosive attack from common electrolytes and is solderable. The subsequent metal layer consists of silver alloyed with a noble metal selected from the group consisting of gold, palladium, platinum, rhenium and osmium. The alloy layer may be formed by covering the barrier layer with a layer of silver and then a layer of gold or one of the other metals. The layered stainless steel body is heated to a temperature below the melting point temperature of the metal layer having the lowest melting point so that the layers, with the exception of the barrier layer, diffuse into one another, thereby forming the alloy layer overlaying the barrier layer which is resistant to corrosive attack from common electrolytes and is solderable. The stainless steel body is rendered solderable.

21 citations


Patent
Bruce E Scott1
24 Dec 1969
TL;DR: In this article, the authors present a scenario in which a base metal member has a SILVER HEAT-CONDUCTing and FATIGUE-RESISTant INTERMEDIATE LAYER and a BEARING SURFACE of LEAD-TIN ALLOY, with a PURE TIN BARRIER LAYer BETWEEN the LEADTIN AllOY and the SILVER to control DIFFUSION and MIGRATION of the TIN from the ALLOY in order to maintain CORROSION RESISTance of the BE
Abstract: A JOURNAL BEARING STRUCTURE IN WHICH A BASE METAL MEMBER HAS A SILVER HEAT-CONDUCTING AND FATIGUE-RESISTANT INTERMEDIATE LAYER AND A BEARING SURFACE OF LEAD-TIN ALLOY, WITH A PURE TIN BARRIER LAYER BETWEEN THE LEAD-TIN ALLOY AND THE SILVER TO CONTROL DIFFUSION AND MIGRATION OF THE TIN FROM THE ALLOY IN ORDER TO MAINTAIN CORROSION RESISTANCE OF THE BEARING SURFACE.

14 citations


Journal ArticleDOI
TL;DR: In this paper, the authors discuss the four reactions responsible for the majority of the observed metalization failures: migration of aluminum under silicon dioxide layers, movement of silicon through both gold and aluminum wires resulting in loss of mechanical strength, structural changes in the molybdenum-gold system occurring during temperature storage testing, and electrochemical attack of the barrier layer resulting from humidity storage testing with applied bias.
Abstract: Chemical and metallurgical changes in IC metalization systems have been studied during a program of device reliability testing and evaluation. This paper discusses the four reactions responsible for the majority of the observed metalization failures: 1) migration of aluminum under silicon dioxide layers, 2) movement of silicon through both gold and aluminum wires resulting in loss of mechanical strength, 3) structural changes in the molybdenum-gold system occurring during temperature storage testing, and 4) the electrochemical attack of the molybdenum barrier layer resulting from humidity storage testing with applied bias. Using standard optical techniques and a commercially available electron beam microanalyzer/scanning electron microscope, the following results were obtained. 1) At temperatures near the silicon-aluminum eutectic point, aluminum migrated under the thermally grown oxide in the form of triangles oriented with respect to the underlying silicon. Aluminum migration was observed at lower temperatures when bias was applied to the device. This occurred at the interface of the thermal silicon dioxide and a vapor deposited glass. 2) Silicon precipitation at wire grain boundaries was observed in both aluminum and gold lead wires. The mechanisms of solid-state diffusion and high-current density electromigration of silicon resulted in wire fracture or slip at grain boundaries in the wires. 3) Silicon penetration into gold conductor stripes through defects in the molybdenum barrier layer resulted in severe reordering of the gold at temperatures in excess of 300°C. The silicon-gold eutectic was formed at temperatures greater than 370°C causing complete dewetting of the molybdenum layer. At lower temperatures, grain boundary flaking due to loss of gold cohension and adhesion was observed. 4) Whiskers which formed on molybdenum barrier layers during 85-85 humidity storage testing with applied bias contained high concentrations of sodium. Several known compounds of sodium and molybdenum are discussed in light of the X-ray data taken on the electron beam microprobe.

13 citations


Patent
Alfred M Mayo1
21 May 1969
TL;DR: In this article, fuel cell units are stacked in facewise relation to make box like structure and electrically connected in series of working voltage, each unit comprises fuel and oxidant electrode layers spaced by permeable insulating layer to provide electrolyte passage.
Abstract: Battery is made very light, and efficient by making fuel cell units very thin and generally flat and rectangular. Cell units are stacked in facewise relation to make box like structure and electrically connected in series of working voltage. Each unit comprises fuel and oxidant electrode layers spaced by permeable insulating layer to provide electrolyte passage. Impervious, conductive barrier layer between each pair of adjacent cell units and in contact with both. In one form barrier layer has protuberances on each side contacting units to provide fuel and oxidant gas passages. Insulating layer has wettable surfaces and maintains electrolyte in contact with electrodes for high efficiency. It is about .010 inch or less thick to produce minimum ion path. Electrode layers are about .005 inch thick or less. All elements are held in tight facewise contact for compactness and also to cause all elements to provide structural support for each other.

12 citations


Patent
26 Aug 1969
TL;DR: A plural-color cathodoluminescent screen for use in a cathoderay tube is described in this paper, where at least two layers of light-emitting phosphors have therebetween a separation layer of electrically conductive oxide material that is substantially translucent to electromagnetic radiation and substantially opaque to the penetration of electron beams of a predetermined velocity.
Abstract: A plural-color cathodoluminescent screen for use in a cathoderay tube wherein at least two layers of light-emitting phosphors have therebetween a separation layer of electrically conductive oxide material that is substantially translucent to electromagnetic radiation and substantially opaque to the penetration of electron beams of predetermined velocity. The screen includes a nucleation to achieve the uniform disposition of an oxidizable metal which when subsequently heated forms the metallic oxide of the separation layer.

9 citations



Patent
Sami I. Gabrail1
11 Dec 1969
TL;DR: In this article, an improved thin film capacitor structure and a method for making the same was described. But the thin film capacitance structure is not suitable for high temperature and the dielectric layer of the capacitance is not available.
Abstract: This invention relates to an improved thin film capacitor structure and a method for making the same. The thin film capacitor comprises two layers of aluminum separated by a dielectric layer. Interposed between one of the aluminum layers and the dielectric layer is a barrier layer which prevents the various mentioned layers from alloying together in the temperature range of 400* to 600* C.

5 citations


Journal ArticleDOI
TL;DR: In this paper, the polarization method proposed by M. S. Hunter and P. Fowle was used to determine the thickness of the barrier layer formed in the air with increasing time of immersion in pure water.
Abstract: Barrier layer thickness of aluminum, which had been subjected to corrosion tests in water containing a few ppm of various reagents, was determined by the polarization method proposed by M. S. Hunter and P. Fowle.The thickness of barrier layer formed in the air decreased with increasing time of immersion in pure water up to 100hrs. The same behavior was also observed on aluminum tested in water containing any one of NaNO3, NaCl, NaOH, and HCl. While, in water containing any one of NaF, Na2SO4, Na2SiO3, H2SO4, and H3PO4, the thickness of the layer formed in the air once decreased at the initial stage of immersion, and then, began to increase.These results were compared with the corrosion rate of aluminum tested in the solutions mentioned above.It was concluded that there was inverse correlation between the corrosion rate of aluminum and the barrier layer thickness after the tests in the various testing solutions for 100hrs. Further studies shall be made in future to reveal the reason of specific effects of anion in testing solutions on the barrier layer thickness of aluminum which was immersed in the solutions.

Patent
15 Oct 1969
TL;DR: A soda-glass is a glass containing 1% or more by weight of Na 2 0.1,171 as discussed by the authors, and it is composed of a glass substrate covered by a layer of a continuous barrier material.
Abstract: 1,167,171. Coating by vapour deposition. PAINTON & CO. Ltd. Aug.22, 1967 [May 31, 1966], No.24284/66. Heading C7F. [Also in Division H1] An electrical component e.g. resistor, comprises a soda-glass substrate covered directly by a layer of a continuous barrier material impermeable to alkali ions and on which is deposited directly an electrically resistive film e.g. nickel-chromium, soda-glass in the context of the Specification is a glass containing 1% or more by weight of Na 2 0. The barrier layer, which may be a mixture of silicon and silicon dioxide, or magnesium fluoride, is said to prevent migration of alkali ions from the substrate into the resistive film. The barrier layer may be between 1, 000 and 5, 000 A thick, deposited by evaporation and deposition from the vapour state.

Patent
17 Sep 1969
TL;DR: A cleaning device comprises a liminate composed of a layer of soft and pliant material and a layer impervious to bacteria, the layers being attached together and permanently folded into the shape of a box pleat so that an area of the device is constituted by three layers of the laminate as mentioned in this paper.
Abstract: 1,164,121. Pads. N. ROSE. 6 Oct., 1966 [6 July, 1965], No. 551/65. Heading A4F. [Also in Division A5] A cleaning device comprises a liminate composed of a layer of soft and pliant material and a layer of material impervious to bacteria, the layers being attached together and permanently folded into the shape of a box pleat so that an area of the device is constituted by three layers of the laminate. The pliant material may be tissue paper or crepe paper or the layer thereof may be formed in situ by spraying the barrier layer with wool or with cellulose in powder or fibrous form. The barrier layer may be polyethylene, regenerated cellulose, metal foil or lacquered paper.

Patent
19 Feb 1969
TL;DR: A scouring pad is a solid cleaning composition 6 enclosed in an envelope 4 which forms a barrier layer 4 between the cleaning composition and an abrasive element 2, the barrier layer being of material that contains voids and the abrasive elements being an open structured web formed of non-absorbent and non-matting synthetic fibres which are resistant to abrasion and water, the fibres being held in random arrangement to form a non- woven, lofty, three-dimensional structure as mentioned in this paper.
Abstract: 1,143,238. Scouring pads. UNILEVER Ltd. 10 Nov., 1966 [12 Nov., 1965], No. 48096/65. Heading A4F. A scouring pad comprises a solid cleaning composition 6 enclosed in envelope 4 which forms a barrier layer 4 between the cleaning composition and an abrasive element 2, the barrier layer 4 being of material that contains voids and the abrasive element being an open structured web formed of non-absorbent and non- matting synthetic fibres which are resistant to abrasion and water, the fibres being held in random arrangement to form a non- woven, lofty, three-dimensional structure. The abrasive element 2 which may surround the barrier layer 4 and may be attached thereto may comprise fibres of polyamide polyester, polypropylene, rayon cellulose acetate and nylon &c. and abrasive particles such as silicon carbide, alumina, carborundum, felspar or china clay may be dispersed on or in the element 2. The barrier layer 4 may be of natural or synthetic foam, cellular foam, woven, knitted or non-woven fabrics and the cleaning composition may be a soap or non- soap detergent. The edges of the barrier layer 4 and abrasive element 2 may be heat sealed or adhered together. The pad may be provided with a coating of rapidly dissolving soap on the abrasive element 2 or the outer surface of the barrier layer 4 and also with a layer of foam material between the barrier layer 4 and abrasive element 2.