Abstract: A semiconductor integrated circuit device is implemented by circuit components and a multi-layered wiring structure, and titanium nitride is used for a part of the integrated circuit such as a conductive plug, an accumulating electrode and a conductive line, wherein the titanium nitride layer is laminated on a titanium silicide layer so as to absorb thermal stress due to the titanium nitride layer.

Abstract: A fabrication process of a non-volatile semiconductor memory device includes the step of forming a plurality of openings in a device isolation structure defining an active region in a memory cell region such that each opening exposes the substrate surface extends from the active region to the outside thereof. Further, silicide regions are formed in the openings by a self-aligned process such that the silicide regions are mutually separated. Further a contact hole is formed in an interlayer insulation film in correspondence to the silicide regions.

Abstract: Container structures for use in integrated circuits and methods of their manufacture. The container structures include a bottom conductive layer, a top conductive layer and a dielectric layer interposed between the bottom conductive layer and the top conductive layer. The container structures further include a diffusion barrier layer interposed between the dielectric layer and the bottom conductive layer. The diffusion barrier layer acts to inhibit atomic diffusion to at least a portion of the bottom conductive layer, particularly atomic diffusion of oxygen during formation or annealing of the dielectric layer. The container structures are especially adapted for use as container capacitors. The container capacitors are further adapted for use in memory cells and apparatus incorporating such memory cells, as well as other integrated circuits.

Abstract: A gate electrode, in which the slope of the profile of a gate electrode forming material layer, for example, a refractory metal silicide layer is prevented from being decreased due to thermal expansion by patterning a refractory metal silicide layer after performing a thermal process on a refractory metal silicide layer, thereby having a stable operation characteristic, and a method for manufacturing the same are provided.

Abstract: Deleterious roughness of metal silicide/doped Si interfaces arising during conventional salicide processing for forming shallow-depth source and drain junction regions of MOS transistors and/or CMOS devices due to poor compatibility of particular dopants and metal suicides is avoided, or at least substantially reduced, by implanting a first (main) dopant species having relatively good compatibility with the metal silicide, such that the maximum concentration thereof is at a depth above the depth to which silicidation reaction occurs and implanting a second (auxiliary) dopant species having relatively poor compatibility with the metal silicide, wherein the maximum concentration thereof is less than that of the first (main) dopant and is at a depth below the depth to which silicidation reaction occurs. The invention enjoys particular utility in forming NiSi layers on As-doped Si substrates.

Abstract: The present invention provides a semiconductor device having a metal suicide layer and a method for forming the metal silicide layer, the semiconductor device having a metal silicide-semiconductor contact structure, wherein the semiconductor device includes a substrate, an insulation layer with an opening, in which a metal silicide layer is formed using a native metal silicide with a first phase and a second phase, upon which a conductive layer is formed. The second phase has a first stoichiometrical composition ratio different from a second stoichiometrical composition ratio of the first phase. A reaction between the metal silicide layer of the first phase and the silicon results in the metal silicide layer of the second phase having high phase stability and low resistance.

Abstract: A ferroelectric structure on an integrated circuit and methods of making and using the same are disclosed, which may be used, for instance, in a high-speed, non-volatile, non-destructive readout random-access memory device. Generally, the ferroelectric structure combines a thin film ferroelectric variable resistor and a substrate (e.g. silicon) transistor, using a semiconducting film which is common to both. A field effect transistor 26 integrated into substrate 30 has a gate oxide 36 and a semiconducting gate electrode 38 with electrical connections at a first end 44 and a second end 46. Overlying gate electrode 38 is a ferroelectric thin film 40 and a conductive electrode 42. The polarization of ferroelectric thin film 40 is set by applying an appropriate voltage between gate electrode 38 and conductive electrode 42.

Abstract: A semiconductor barrier layer and manufacturing method therefor for copper interconnects which is a tantalum-titanium, tantalum-titanium nitride, tantalum-titanium sandwich. The tantalum in the tantalum-titanium alloy bonds strongly with the semiconductor dielectric, the tantalum-titanium nitride acts as the barrier to prevent diffusion of copper, and the titanium bonds strongly with the copper.

Abstract: AS conductive patterns 11A to 11D are formed burying in a insulating resin 10 and a conductive foil 20 is formed being half-etched, thickness of the device is made thin. As an electrode for radiation 11D is provided, a semiconductor device superior in radiation is provided.

Abstract: A method of providing sub-half-micron copper interconnections with improved electromigration and corrosion resistance. The method includes double damascene using electroplated copper, where the seed layer is converted to an intermetallic layer. A layer of copper intermetallics with hafnium, lanthanum, zirconium or tin, is provided to improve the electromigration resistance and to reduce defect sensitivity. A method is also provided to form a cap atop copper lines, to improve corrosion resistance, which fully covers the surface. Structure and methods are also described to improve the electromigration and corrosion resistance by incorporating carbon atoms in copper interstitial positions.

Abstract: A semiconductor device including: a semiconductor substrate, and an interconnect made of a titanium silicide film overlying the semiconductor substrate, the titanium silicide film including at least one atom selected from the group consisting of phosphorus, arsenic and antimony at an average density between 5×1019 and 3×1020 atoms/cm3. Although the titanium silicide film is conventionally recognized to cause depletion of an underlying polysilicon and increase of a connected-polysilicon-plug resistance, these deficiencies can be suppressed by specifying the average density.

Abstract: A semiconductor device with improved reliability is achieved by forming a gate electrode structure over a substrate, the gate electrode structure including a gate electrode over the substrate, an insulator on the gate electrode, and a sidewall spacer adjacent to the gate electrode and to the insulator thereon. The insulator is then removed to form a gap between the gate electrode and the sidewall spacer. Upon applying a salicide process to the gate electrode structure to form a salicide layer over the entire structure, the gap prevents bridging of salicide material formed on the gate electrode structure with the salicide material formed on the substrate.

Abstract: A chip-type multi-layered electronic part in which terminal electrodes are prevented from oxidization when the electrical part is joined with a substrate, so that superior electrical bonding between the terminal electrodes and internal electrodes can be attained. Terminal electrodes 7 connected to internal electrodes 1 contain silver and palladium as the main ingredients in the weight ratio in a range of from 7:3 to 3:7, and further contain boron in a range of from 0.1 weight percent to 1.0 weight percent added to the main ingredients of 100 weight percent.

Abstract: On a silicon substrate, silicon oxide film is formed. On the silicon oxide film, a BPSG film is formed. On the BPSG film, a silicon oxide film which does not include at least phosphorus and has a thickness equal to or more than about 1 &mgr;m is formed as a protective film. On the silicon film, a fuse is formed. Covering the fuse, a silicon oxide film which does not include at least phosphorus is formed on the silicon oxide film. Thus, the corrosion of the fuse is prevented, whereby a semiconductor device with highly reliable metal interconnection can be obtained.

Abstract: A method of manufacturing a semiconductor device in which a cobalt silicide layer is formed on a semiconductor substrate. In the method, the semiconductor substrate is prepared, and cobalt is deposited on the semiconductor substrate by sputtering while heating the semiconductor substrate at a temperature approximately equal to 200 degrees Celsius. Thereafter, cobalt is deposited on the semiconductor substrate by sputtering while heating the semiconductor substrate at a temperature between 300 degrees Celsius and 400 degrees Celsius without exposing the semiconductor substrate to the atmosphere. Preferably, the semiconductor substrate is thereafter rapid thermal annealed at a temperature equal to or higher than 500 degrees Celsius in nitrogen atmosphere for a predetermined time. Further, at least a part of cobalt portion or cobalt oxide portion on the semiconductor substrate is removed by wet etching.

Abstract: For forming a contact electrode to an n-type contact layer of a gallium nitride-based compound semiconductor, the n-type contact layer of the gallium nitride-based compound semiconductor is exposed to an oxygen plasma to form an oxygen-doped surface layer in a surface of the n-type contact layer, and then, an electrode metal is formed on the oxygen-doped surface layer. With this arrangement, an n-type contact electrode having a low specific contact resistance is obtained with good reproducibility, with performing no annealing after formation of the electrode metal.

Abstract: A process for the formation of metal salicide regions and metal salicide exclusion regions in an integrated circuit (IC) that requires a minimum number of steps and is compatible with standard MOS processing techniques. In the process, an IC structure is first provided. The IC structure includes a plurality of MOS transistor structures with exposed silicon surfaces, such as source regions, drain regions and polysilicon gates. A metal layer (e.g., cobalt, titanium, tantalum, nickel or molybdenum) is then deposited over the IC structure, followed by the formation of a photoresist masking layer on those MOS transistor structures where metal salicide regions are to be formed. The metal layer from those MOS transistor structures where metal salicide exclusion regions are to be formed is then removed, followed by stripping of the photoresist masking layer from those MOS transistor structures where metal salicide regions are to be formed.

Abstract: The present invention relates to a semiconductor structure including metal nitride and metal silicide, where a metal silicide layer is formed upon an active area that is part of a junction in order to facilitate further miniaturization that is demanded and dictated by the need for smaller devices. A single PECVD process makes three distinct depositions. First, a metal silicide forms by the reaction: MHal+Si+H2→MSix+HHal, where M represents a metal and Hal represents a preferred halogen or the like. Second, a metal nitride forms upon areas not containing Si by the reaction: MHal+N2+H2→MN+HHal. Third, a metal nitride forms upon areas of evolving metal silicide due to a diffusion barrier effect that makes formation of the metal silicide self limiting. Ultimately, a metal nitride layer will be uniformly disposed in a substantially uniform composition covering all underlying structures upon a semiconductor substrate.

Abstract: Integrated circuit devices produced by a method in which devices are formed and packaged at the wafer scale. The integrated circuit device includes bond pads on a first side thereof, a layer of glass adhesively affixed to the first side, a layer of sealant covering the second side and edges thereof, and a metallization pattern on the layer of glass connected via an array of contact holes to the bond pads on the integrated circuit device. The device is advantageously formed with an etchable glass package and palladium metallization pattern.

Abstract: A method for forming a quaternary alloy film of Co—W—P—Au for use as a diffusion barrier layer on a copper interconnect in a semiconductor structure and devices formed incorporating such film are disclosed. In the method, a substrate that has copper conductive regions on top is first pre-treated by two separate pre-treatment steps. In the first step, the substrate is immersed in a H2SO4 rinsing solution and next in a solution containing palladium ions for a length of time sufficient for the ions to deposit on the surface of the copper conductive regions. The substrate is then immersed in a solution that contains at least 15 gr/l sodium citrate or EDTA for removing excess palladium ions from the surface of the copper conductive regions.

Abstract: The present invention provides a method for forming a substantially carbon- and oxygen-free conductive layer, wherein the layer can contain a metal and/or a metalloid material. According to the present invention, a substantially carbon- and oxygen-free conductive layer is formed in an oxidizing atmosphere in the presence of an organometallic catalyst using, for example, a chemical vapor deposition process. Such layers are particularly advantageous for use in memory devices, such as dynamic random access memory (DRAM) devices.

Abstract: The integrated semiconductor memory configuration has a semiconductor body in which selection transistors and storage capacitors are integrated. The storage capacitors have a dielectric layer configured between two electrodes. At least the upper electrode is constructed in a layered manner with a platinum layer, that is seated on the dielectric layer, and a thicker, base metal layer lying above the platinum layer.

Abstract: Methods of forming a graded layer is disclosed. The graded layer transitions from one material to another material. The properties of these materials are chosen to optimize the interfaces on each side of the graded layer. Specifically, an improved transistor gate stack barrier layer may be formed by disposing an appropriate graded layer between a gate layer and an interconnect layer. In fact, the graded layer may obviate the use of the interconnect layer, as the top of the graded layer may include a highly conductive material. An improved integrated circuit interconnect structure may also be formed by grading the material composition of an interconnect layer.

Abstract: A metal-line structure in an integrated circuit (IC) and a method of fabricating the same are provided. The metal-line structure includes a barrier layer formed at a selected location over the dielectric layer, a metallization layer formed over the barrier layer, an ARC formed over the metallization layer, and a spacer structure formed over all the exposed sidewalls of the barrier layer, the metallization layer, and the ARC. The forming of the spacer structure on each of the metal lines can help prevent the occurrence of extrusions along the sidewalls of the metal lines in the IC device that would otherwise cause dielectric cracks and thus lead to undesired bridging between neighboring metal lines as in the prior art. Moreover, the method of fabricating such a metal-line structure can be carried out without having to perform photolithography, thus reducing manufacturing cost.

Abstract: A conductive connection forming method includes forming a first layer comprising a first metal on a substrate and forming a second layer comprising a second metal different from the first metal on the first layer. At least a part of the first layer may be transformed to an alloy material comprising the first and second metals. A conductive connection may be formed to the alloy material. The alloy material may be less susceptible to formation of metal oxide compared to the first metal. By way of example, transforming the first layer may comprise annealing the first and second layer. An exemplary first metal comprises copper, and an exemplary second metal comprises aluminum, titanium, palladium, magnesium, or two or more such metals. The alloy material may be an intermetallic. A conductive connection may be formed to the alloy layer.

Abstract: Electrical shorts and leakage paths are virtually eliminated by recessing conductive nodules (52) away from a conductor (72) or not forming the conductive nodules at all. In one embodiment, the refractory metal containing material (52) is recessed from the edge of the opening (32). When forming a nitride layer (54) within the opening (32), conductive nodules (52) are formed from a portion of the refractory metal containing material (20) such that the conductive nodules (52) lie within the recession (42). In another embodiment, an oxide layer (82, 102) is formed adjacent to the refractory metal containing material (20) before forming a nitride layer (84, 112).

Abstract: An interconnect structure and barrier layer for electrical interconnections is described incorporating a layer of TaN in the hexagonal phase between a first material such as Cu and a second material such as Al, W, and PbSn. A multilayer of TaN in the hexagonal phase and Ta in the alpha phase is also described as a barrier layer. The invention overcomes the problem of Cu diffusion into materials desired to be isolated during temperature anneal at 500° C.

Abstract: A layer comprising cobalt (Co) is formed on a p+ layer by vapor deposition, and layer comprising gold (Au) is formed thereon. The two layers are alloyed by a heat treatment to form a light-transmitting electrode. The light-transmitting electrode therefore has reduced contact resistance and improved light transmission properties, and gives a light-emitting patten which is stable over a long time. Furthermore, since cobalt (Co) is an element having a large work function, satisfactory ohmic properties are obtained.

Abstract: A method of fabricating a semiconductor device is provided, which decreases the parasitic wiring capacitance among adjoining Cu-based wiring lines is provided and which prevents the oxidation of Cu-based wiring lines and the diffusion of the Cu atoms existing in the wiring lines.

Abstract: A dielectric film (110) is formed overlying a semiconductor device substrate (10). A dielectric post (204) having an outer peripheral boundary having sidewalls is formed over the dielectric film (110). A first conductive film (402) is deposited at least along the sidewalls of the dielectric post (204) to form a lower electrode. A capacitor dielectric film (1801) is deposited on the first conductive film, and a upper electrode (1802) is formed on the capacitor dielectric film (1801).

Abstract: Methods of forming a graded layer is disclosed. The graded layer transitions from one material to another material. The properties of these materials are chosen to optimize the interfaces on each side of the graded layer. Specifically, an improved transistor gate stack barrier layer may be formed by disposing an appropriate graded layer between a gate layer and an interconnect layer. In fact, the graded layer may obviate the use of the interconnect layer, as the top of the graded layer may include a highly conductive material. An improved integrated circuit interconnect structure may also be formed by grading the material composition of an interconnect layer.

Abstract: The present invention provides a semiconductor device which can prevent the oxidization of the surfaces of pad electrodes to enhance the connecting strength between the pad electrodes and external terminals. The semiconductor device according to the present invention comprises pad electrodes for use in connecting external electrodes and a multilayer wiring structure connected to the pad electrodes, wherein one surface of an insulating layer covering the pad electrodes and having openings over the pad electrodes for exposing the surfaces of the pad electrodes is in contact with a metal layer formed from one selected from precious metals and alloys containing the precious metals as main components.

Abstract: The present invention is directed toward the formation of implanted thermally and electrically conductive structures in a dielectric. An electrically conductive structure, such as an interconnect, is formed through ion implantation into several levels within a dielectric layer to penetrate into an electrically conductive region beneath the dielectric layer, such as a semiconductor substrate. Ion implantation continues in discreet, overlapping implantations of the ions from the electrical conductive region up to the top of the dielectric layer so as to form a continuous interconnect. Structural qualities achieved by the method of the present invention include a low interconnect-conductive region resistivity and a low thermal-cycle stress between the interconnect and the dielectric layer in which the interconnect has been implanted.

Abstract: A semiconductor substrate adapted to giga-scale integration (GSI) comprises a support, at least the surface of which is made of semiconductor, an electroconductive material layer, an insulating layer and a semiconductor layer arranged sequentially in the above order. The electroconductive material layer has at least in part thereof an electroconductive reacted layer obtained by causing two metals, a metal and a semiconductor, a metal and a metal-semiconductor compound, a semiconductor and a metal-semiconductor compound, or two metal-semiconductor compounds to react each other. An electroconductive reaction terminating layer that is made of a material that does not react with the reacted layer is arranged between the reacted layer and the insulating layer or the support.

Abstract: In a trench capacitor type semiconductor memory device including a semiconductor substrate having a trench and first and second impurity diffusion source/drain regions, a capacitor electrode buried in the trench, and a substrate-side capacitor electrode and a capacitor insulating layer within the semiconductor substrate and adjacent to a lower portion of the capacitor electrode, a buried insulating layer is formed between the semiconductor substrate and an upper portion of the capacitor electrode. The buried insulating layer is thicker than the capacitor insulating layer. However the buried insulating layer on a surface of the second impurity diffusion source/drain region is thin, or in direct contact with the capacitor electrode. A silicide layer is formed on the second impurity diffusion source/drain region and the capacitor electrode.

Abstract: Interlevel contacts in semiconductor integrated circuits are fabricated by formation of a contact opening through an insulating layer. A layer of refractory metal, or refractory metal alloy, is deposited over the surface of the integrated circuit chip. An aluminum layer is then deposited at a significantly elevated temperature, so that an aluminum/refractory metal alloy is formed at the interface between the aluminum layer and the refractory metal layer. Formation of such an alloy causes an expansion of the metal within the contact opening, thereby filling the contact opening and providing a smooth upper contour to the deposited aluminum layer.

Abstract: A semiconductor device having a contact layer and a diffusion barrier layer is fabricated by preparing a semiconductor substrate forming a layer of titanium/aluminum alloy on the surface of the substrate and then heating the resultant structure in a nitrogen ambient to form a contact layer of titanium silicide interposed between the substrate and a diffusion barrier layer consisting of titanium/aluminum/nitride.

Abstract: A process for producing a terminal metal pad structure electrically interconnecting a package and other components. More particularly, the invention encompasses a process for producing a plurality of corrosion-resistant terminal metal pads. Each pad includes a base pad containing copper which is encapsulated within a series of successively electroplated metal encapsulating films to produce a corrosion-resistant terminal metal pad.

Abstract: A semiconductor device is formed by forming a groove portion whose side surface is formed of a first insulating film and whose bottom surface is formed of a silicon film on the main surface of a semiconductor substrate, forming a metal film on the silicon film of a bottom portion of the groove portion, reacting the silicon film with the metal film by a heat treatment to selectively form a silicide film on the bottom portion of the groove portion, removing the metal film other than a portion thereof which has been converted to metal silicide after the metal silicide layer is formed, and forming a second insulating film on the metal silicide film to form one of a wiring and an electrode which is covered with the first and second insulating films.

Abstract: Multilayer metal materials are selected so that the materials will alloy or intermix under rapid thermal annealing conditions. The individual materials of the multilayers are preferably chosen such that at least one of the materials may be selectively etched with respect to the other material by wet chemical or electrochemical etching. For electroplating applications, the alloyed plating base material will assume some of the etch resistance of the original electrodeposit material such that a selective wet etch of the plating base can be performed without substantial undercutting. Furthermore, the graded composition alloy will exhibit other advantageous physical and chemical properties for electrode formation and use. The alloying or intermixing may be accomplished before or after patterning of the materials, for the instance wherein the materials deposited as blanket layers.

Abstract: A method of constructing a conductive via spacer within a dielectric layer located between a first metal layer and a second metal layer includes the steps of depositing a conductive spacer layer within the opening and over the first metal layer. A portion of the conductive spacer layer is removed to leave a conductive spacer within the opening. The second metal layer is deposited over the spacer to complete the connection between the first and second metal layers. The spacer preferably comprises a material selected from the group comprising refractory metal silicides and nitrides. The spacer is preferably tapered and the via may include a glue layer to improve the adherence of the spacer to the dielectric layer.

Abstract: A method for forming the gate electrode in an integrated circuit, in which a cap silicon nitride layer is deposited in a two step process to improve the condition of silicon nitride residue remaining on the surface of tungsten silicide. First, a layer of polysilicon and a layer of tungsten silicide are sequentially formed on the semiconductor substrate, subsequently, a thin film of silicon nitride is formed at a first temperature and a second silicon nitride is formed at a second temperature, then the pattern of the contact window of gate is defined and the first etching is performed to remove the second and the second silicon nitride, finally, the second etching is performed to remove the layers of polysilicon and tungsten silicide to form a gate electrode.

Abstract: A homojunction bipolar transistor with performance characteristics similar to more costly heterojunction or retrograde base transistors. The high emitter resistivity found in prior homojunction devices is circumvented using a low work function material layer in forming the emitter. This produces an economically viable high performance alternative to SiGe HBTs or SiGe retrograde base transistors.

Abstract: A method and arrangement for forming a local interconnect without weakening the field edge or disconnecting the diffusion region at the field edge introduces additional nitrogen by ion implantation into a nitrogen-containing etch stop layer (e.g., SiON) that has already been deposited, by plasma enhanced chemical vapor deposition (PECVD), for example. The enriched nitrogen etch stop layer is harder to etch than conventional PECVD SiON so that when etching the dielectric layer in which the local interconnect material is subsequently deposited, the etching stops at the etch stop layer in a controlled manner. This prevents the unintentional etching of the silicide region and diffusion region at the field edge.

Abstract: An article comprising a metal circuit and/or a heat-radiating metal plate formed on a ceramic substrate, wherein the metal circuit and/or the heat-radiating metal plate comprise either (1) the following first metal-second metal bonded product, wherein the first metal and the second metal are different, or (2) the following first metal-third metal-second metal bonded product, and wherein in (1) and (2), the first metal is bonded to the ceramic substrate; first metal: a metal selected from the group consisting of aluminum (Al), lead (Pb), platinum (Pt) and an alloy containing at least one of these metal components; second metal: a metal selected from the group consisting of copper (Cu), silver (Ag), gold (Au), aluminum (Al) and an alloy containing at least one of these metal components; and third metal: a metal selected from the group consisting of titanium (Ti), nickel (Ni), zirconium (Zr), molybdenum (Mo), tungsten (W) and an alloy containing at least one of these metal components.

Abstract: A leadframe having the desirable features of palladium plated leadframes, such as compatibility with both wire bonding and solder reflow, as well as good adhesion to molding compounds is provided by plating the interior lead frame portions with one microinch of palladium and the external leads which contact solder with three microinches of palladium. A low cost method for fabricating the leadframe based on a unique combination of proven processes is provided.

Abstract: A microelectronic structure including adjacent material layers susceptible of adverse interaction in contact with one another, and a barrier layer interposed between said adjacent material layers, wherein said barrier layer comprises a binary, ternary or higher order metal nitride-carbide material, whose metal constituents are different from one another and include at least one metal selected from the group consisting of transition metals Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, W, Sc and Y, and optionally further including Al and/or Si. The barrier layer is stoichiometrically constituted to be amorphous or nanocrystalline in character, and may be readily formed by techniques such as chemical vapor deposition, sputtering, and plasma-assisted deposition, to provide a diffusional barrier of appropriate resistivity character for structures such as DRAMs or non-volatile ferroelectric memory cells.

Abstract: In a semiconductor storage device in a stack structure wherein a capacitor section having an upper electrode, a dielectric layer, and a lower electrode is connected with a transistor section by a plug, the lower electrode is formed in contact with the plug. The lower electrode is formed of at least an oxide of a platinum-rhodium alloy. In addition to the oxide of a platinum-rhodium alloy, platinum and/or a platinum-rhodium alloy can be used as materials for forming the lower electrode. The plug is formed of polysilicon or tungsten. When the plug is formed of polysilicon, the lower electrode is formed by sequentially laminating, for example, a film of the oxide of the platinum-rhodium alloy, a film of the platinum-rhodium alloy, and a film of the oxide of the platinum-rhodium alloy on the plug.

Abstract: A lead frame lead and method of fabrication of the leadframe. A leadframe is formed from one of copper or copper-based material having a layer of an alloy of palladium and nickel and a coating of palladium formed over the alloy on the leadframe. The coating of palladium is from about 3 to about 10 microinches and preferably about 3 microinches. The palladium/nickel layer is from about 10 to about 40 microinches and preferably about 10 microinches and is an alloy having from about 40 to about 90 percent by weight nickel and the remainder essentially palladium. A preferred ratio is 75 percent by weight nickel and 25 percent by weight palladium. A semiconductor device is fabricated by providing a copper or copper-based leadframe and forming a layer of the palladium/nickel alloy over the entire leadframe followed by a palladium layer thereover while maintaining the assembly temperature below about 180 degrees C during subsequent device assembly.

Abstract: The present invention relates to mounting an electric connector (20) onto a printed circuit board, particularly to a printed circuit board comprised of ceramic material, for instance either an LTCC substrate or an HTCC substrate. The problem addressed is one where the connector (20) tends to loosen from the substrate when the temperature varies. This is due to the difference in the coefficients of thermal expansion of the printed circuit board and the connector (20). The problem is solved with the aid of a so-called shim (10) that has a coefficient of thermal expansion between that of the printed circuit board and that of the connector. One side of the shim (10) is soldered onto the connector and the other side of the shim is soldered onto the printed circuit board. The connector (20) is therewith fastened to the printed circuit board. Shear stresses acting between the connector (20) and the printed circuit board are distributed through said board through the medium of two joints instead of one.