1274results about How to "Improve joint strength" patented technology

A lead frame comprising a frame which defines a central opening. Disposed within the central opening is a die pad which is connected to the frame. Also connected to the frame are a plurality of leads which extend within the opening toward the die pad. Each of the leads defines opposed top and bottom surfaces, an inner end, an outer end, and an opposed pair of side surfaces. The bottom surface and the outer end collectively define a corner region of the lead. Formed within the corner region is a recess which is sized and configured to accommodate the flow of reflow solder thereinto.

There is provided method for joining dissimilar metals of a steel product and a light metal product with each other, wherein the light metal product and a rivet made of an iron-base metal are connected with each other beforehand in a previous process preceding spot welding, and subsequently, the rivet and the steel product are spot welded with each other. Then, a cavity for use in clinching the light metal product is formed, and upon the stem of the rivet is embedded into the light metal product to penetrate therethrough, light metal is caused to undergo plastic flow into the cavity of the rivet, for clinching the light metal product to be thereby clinched with the rivet whereupon spot welding for forming a weld nugget only within the scope of an interface between the stem of the rivet, and the steel product is carried out. Thus, the present invention can implement the spot welding between iron-iron similar metals, without a constraint on, and a problem with conditions applicable to the spot welding and a high joint strength can be obtained owing to the synergistic effect of the spot welding and connection by clinching of the aluminum alloy product with the iron-base rivet, added thereto.

[Object] It is to provide a sputtering target which has an excellent adhesion to films made of Au, Cu or an alloy containing at least one of Au and Cu and also an excellent corrosion resistance and which can be used to form an Mo—Ti alloy film over a large-sized substrate.[SOLUTION] The present invention provides a sputtering target suitable for use in formation of an Mo—Ti alloy film on a substrate, characterized by that the sputtering target comprises Ti of higher than 50 atomic percentages but not exceeding 60 atomic percentages and the balance of Mo and inevitable impurities and that the relative density of the sputtering target is equal to or more than 98%. The present invention also provides a joined type sputtering target assembly formed by diffusion joining two of more of such sputtering targets, the length of the joined type sputtering target assembly being equal to or larger than 1,000 mm at least one side. The present invention further provides a method of making such a joined type sputtering target assembly.

In a structure of a semiconductor device, a Si chip and a metal leadframe are jointed by metallic bond via a porous joint layer made of high conductive metal, having a three-dimensional network structure and using Ag as a bonding material, and a film containing Zn oxide or Al oxide is formed on a surface of a semiconductor assembly contacting to a polymer resin. In this manner, by the joint with the joint layer having the porous structure mainly made of Ag, thermal stress load of the Si chip can be reduced, and fatigue life of the joint layer itself can be improved. Besides, since adhesion of the polymer resin to the film can be enhanced by the anchor effect, occurrence of cracks in a bonding portion can be prevented, so that a highly-reliable Pb-free semiconductor device can be provided.

A gear bearing drive provides a compact mechanism that operates as an actuator providing torque and as a joint providing support. The drive includes a gear arrangement integrating an external rotor DC motor within a sun gear. Locking surfaces maintain the components of the drive in alignment and provide support for axial loads and moments. The gear bearing drive has a variety of applications, including as a joint in robotic arms and prosthetic limbs.

Provided is a spot welded joint (10) which includes at least one thin steel plate with a tensile strength of 750 MPa to 1850 MPa and a carbon equivalent Ceq of equal to or more than 0.22 mass % to 0.55 mass % and in which a nugget (3) is formed in an interface of the thin steel plates (1A, 1B). In a nugget outer layer zone, a microstructure consists of a dendrite structure in which an average value of arm intervals is equal to or less than 12 μm, an average grain diameter of carbides contained in the microstructure is 5 nm to 100 nm, and a number density of carbides is equal to or more than 2×106 / mm2.

A method for improving joint strength between a first and second member comprising the steps of: applying a sealant material including a matrix material at least partially encasing rigid components to the first and second members; joining the first and second members upon an application of force that is applied through the use of one or more fasteners; wherein a compressive force is applied to the exterior surface of both the first and second members by the one or more fasteners while the rigid components apply an internal tension force acting opposite of the compression force to the interior surface of both the first and second members proximate to the fastener to form a mechanical lock thereby reducing slippage and generally maintaining the joint in position.

In accordance with the invention, bodies of materials are joined by disposing between them a reactive multilayer foil and one or more layers of meltable joining material such as braze or solder. The bodies are pressed together against the foil and joining material, and the foil is ignited to melt the joining material. The pressing is near the critical pressure and typically produces a joint having a strength of at least 70-85% the maximum strength producible at practical maximum pressures. Thus for example, reactively formed stainless steel soldered joints that were heretofore made at an applied pressure of about 100 MPa can be made with substantially the same strength at a critical applied pressure of about 10 kPa. Advantages of the process include minimization of braze or solder extrusion and reduced equipment and processing costs, especially in the joining of large bodies.

When a friction stir weld tool penetrates the interface of two workpieces of dissimilar metal alloy materials, the resultant weld of the different alloy materials may produce a weak weld joint. Such weak joints are often experienced, for example, when attempting to form spot welds or other friction stir welds between a magnesium alloy sheet or strip and an aluminum alloy sheet or strip. It is discovered that suitable coating compositions including an adhesive placed at the interface of assembled workpieces can alter the composition of the friction stir weld material and strengthen the resulting bond. In the example of friction stir welds between magnesium alloy and aluminum alloy workpieces, it is found that combinations of an adhesive with copper, tin, zinc, and / or other powders can strengthen the magnesium-containing and aluminum-containing friction stir weld material.

A rotatable tool for friction stir welding a workpiece and an associated apparatus and method are provided. The tool includes a first pin portion that extends from a shoulder and defines a contour surface opposite the shoulder. A second pin portion extends from the contour surface of the first pin portion. The contour surface, which mixes the material of the workpiece during welding, can increase the mixing of the material at the interface, thereby increasing the strength of the joint.

A friction stir welding tool 1 includes a rotor 2 to be attached to a rotation-drive section and a probe 3 concentrically provided on a distal end surface of the rotor 2. A provisional joining projection 4 is concentrically provided on a distal end surface of the probe 3. A relation 0.3 D≦d≦0.8 D is satisfied, where D represents a diameter (mm) of the distal end surface of the probe 3, and d represents a diameter (mm) of the contour of a transverse cross section of the provisional joining projection 4. The provisional joining projection 4 has a length of 0.3 to 2 mm. This friction stir welding tool can improve the work efficiency of friction stir welding and can carry out friction stir welding which is excellent in welding quality after main friction stir welding.

The joining method of the present invention includes a lapping step of lapping the aluminum alloy plate (1) and the plated steel plate (2) via the adhesive (5), a pre-heating step of clamping both of the metal plates (1, 2) that have been lapped in the lapping step between a pair of electrodes (7, 7) for spot welding and applying pressure thereto, and applying a current between the pair of electrodes (7, 7), a cooling step of pressurizing, after the pre-heating step, both of the metal plates (1, 2) at a pressing force which is higher than that at the start of the pre-heating step in a state where conduction between the electrodes (7, 7) is stopped, and continuing this pressurization over a predetermined cooling time, and a welding step of pressurizing, after the cooling step, both of the metal plates (1, 2) at a pressing force which is higher than that at the start of the pre-heating step, and welding both of the metal plates (1, 2) by applying a current which is higher than the conduction current value in the pre-heating step between the pair of electrodes (7, 7). It is thereby possible to firmly join the dissimilar metal plates (1, 2) by combining adhesion due to an adhesive and spot welding.

Disclosed is a package-on-package semiconductor device comprising a bottom package, a top package thereon and a ACA (Anisotropic Conductive Adhesive) layer. A plurality of ball pads are disposed on the peripheries of an upper surface of the substrate of the bottom package. A plurality of solder balls are disposed at the peripheries of the lower surface of the substrate of the top package. The ACA layer having a central opening is interposed between the bottom package and the top package where the ACA layer contains a plurality of conductive particles. Therein, the size of the central opening and the thickness of the ACA layer are selected such that the anisotropic conductive adhesive layer adheres the peripheries of the upper surface of the bottom package to the peripheries of the lower surface of the top package and the solder balls are encapsulated inside the anisotropic conductive adhesive layer. The solder balls encapsulate some of the conductive particles to mechanically joint and electrically connect to the ball pads. Thereby, the bonding strength of the solder balls can be improved and the warpage of the substrate of the bottom package is effectively reduced to avoid failure of electrical connections between both packages caused by the breaking of soldering joints.

The joining method includes a step of lapping the aluminum alloy plate and the plated steel plate via adhesive, a pre-heating step of clamping both metal plates lapped in the lapping step between a pair of electrodes for spot welding and applying pressure thereto, and applying a current between the pair of electrodes, a cooling step of pressurizing both metal plates at a pressing force higher than that at the start of the pre-heating step in a state where conduction between the electrodes is stopped, and continuing this pressurization over a predetermined cooling time, and a welding step of pressurizing both metal plates at a pressing force higher than that at the start of the pre-heating step, and welding both of the metal plates by applying a current higher than the conduction current value in the pre-heating step between the pair of electrodes.

A lead frame adapted to a semiconductor package, which is enclosed in a molded resin body and is connected with a board, is formed by processing a thin metal plate so as to include a stage for mounting a semiconductor chip thereon, a plurality of leads arranged to encompass the stage, and a plurality of lead interconnecting members (or dam bars) for interconnecting the leads together. At least one recess, which is of a circular shape or a non-circular shape, is formed on the backside of the lead (or the lead interconnecting member), which is substantially arranged in the same plane with a terminal surface of the molded resin body. Due to the formation of the recess that is subjected to plating, it is possible to increase the joining strength between the lead and solder; hence, it is possible to improve reliability regarding electric connection between the semiconductor package and board.

The invention provides an aluminium nitride ceramic copper-clad substrate which comprises an aluminium nitride ceramic chip, and a copper foil coated on at least one surface of the aluminium nitride ceramic chip, wherein a metal modification layer is formed between the ceramic chip and the copper foil, and the metal modification layer comprises Cu2O, CuAlO2 and a set of compound selected from the following two set of compounds: (1) TixNy and TiO2 wherein x / y is 0.25 to 1; (2) MnO2. In addition, the invention also provides a preparation method of aluminium nitride ceramic copper-clad substrate. In the invention, with a magnetron sputtering method, a metal mixture coating is formed on the surface of the dense sintering of the aluminium nitride ceramic chip, as the dense sintering of the metal mixture coating through high temperature sintering, the formed metal modification layer can improve the surface of the aluminium nitride ceramics chip and forms a good bonding with the copper foil.

A gear bearing drive provides a compact mechanism that operates as an actuator providing torque and as a joint providing support. The drive includes a gear arrangement integrating an external rotor DC motor within a sun gear. Locking surfaces maintain the components of the drive in alignment and provide support for axial loads and moments. The gear bearing drive has a variety of applications, including as a joint in robotic arms and prosthetic limbs.

A package of the present invention has a laminate structure formed by laminating a plurality of ceramic layers, and has a mount surface to be a joint surface when mounted on a mother board, defined parallel with the laminating direction. A first ceramic layer has a recess with an L-shaped cross section across the mount surface and a side surface, defined at each end thereof in a direction perpendicular to the laminating direction, and an external electrode formed on each recess, the external electrode having a surface thereof exposed to the mount surface.

An improved structure of a spark plug is provided to ensure a high strength of joint between a ground electrode and a metal shell. The ground electrode is resistance-welded to the metal shell so that it is embedded partially in an end surface of the metal shell to create a weld interface extending from the end surface to an inner periphery of the metal shell, thus resulting in an increased size of the weld interface to increase the joint strength. The resistance welding keeps the temperature of a weld between the ground electrode and the metal shell at a lower level during welding as compared with laser welding, thus minimizing solidification cracking in the weld.

In joining an Fe-based metallic member comprising an Fe-based material and an Al-based metallic member comprising an Al-based material by a Zn-based brazing filler metal, a joined part of the Fe-based metallic member is heated at a temperature higher than a melting point of the Fe-based material.

A QFN package with improved joint solder thickness for improved second level attachment fatigue life. The copper leadframe of a QFN chip carrier is provided with rounded protrusions in both the chip attach pad region and the surrounding lead regions before second level attachment. The rounded stand-off protrusions are formed from the copper itself of the copper of the leadframe. This may be achieved by punching dimples into one surface of the copper plate of the leadframe before plating to form protrusions on the opposing surface. This method of forming the rounded protrusions simplifies the process of forming stand-offs. The protrusions provide a structure that increases wetting area and allows the use of a larger quantity of solder for increased solder joint thickness and better die paddle solder joint area coverage. As a result of the increased solder joint thickness, second level fatigue life is significantly improved. As a result of the improved die paddle solder joint area coverage, improved thermal performance of the chip carrier is also significantly improved.

Provided is a tie bag having at least two tie flaps. The tie bag includes a first sidewall and a second sidewall opposing the first sidewall. The first and second sidewalls are coupled by sealing together three of four corresponding peripheral edges of the sidewalls. The fourth peripheral edge of each of the first and second sidewalls remains unsealed to define an opening in the tie bag. The tie flaps are integral with and extend from the opening of the tie bag and are adapted for tying one to another to close the tie bag and to form a handle for the tie bag. Each of the tie flaps includes gripping features embossed on at least one surface of the tie flaps. The tie bag may be formed from a tube of thermoplastic material.