Abstract:
A method for mounting a semiconductor chip onto a substrate comprises the steps of positioning a solder dispenser over the substrate and passing a length of solder wire through the solder dispenser to the substrate. The feeding of the wire to the substrate in a feeding direction is controlled with a wire feeder. The solder dispenser is moved relative to the substrate with a positioning device along at least one of two orthogonal axes that are substantially perpendicular to the feeding direction contemporaneously with feeding the solder wire to the surface of the substrate to dispense a line of molten solder onto the substrate. The semiconductor chip is then mounted onto the molten solder that has been dispensed onto the substrate.
Abstract:
A linear motor comprising a coil assembly and a magnet assembly is provided with a cooling apparatus which comprises a segmented air knife assembly. The segmented air knife assembly has a plurality of slot openings distributed along its length which is coupled to the linear motor and it is operative to discharge cooling air into a gap between the coil assembly and magnet assembly in a discharge direction. An inclined surface extends from the plurality of slot openings and slopes at an obtuse angle away from the discharge direction of the cooling air. Each slot opening is individually configured to discharge the cooling air in the discharge direction at a sufficient velocity so as to entrain atmospheric air along the inclined surface to amplify the cooling air that is so discharged.
Abstract:
A wire bonding apparatus and method in which separate first and second positioning tables are provided for mounting electronic devices to be wire bonded, and a bonding tool is provided at a bonding position for bonding the electronic devices. First and second loading/unloading positions are provided for loading electronic devices to or unloading electronic devices from the positioning tables. The first and second positioning tables are operative to move independently of each other, such that the first positioning table is movable between the first loading/unloading position and the bonding position and the second positioning table is movable between the second loading/unloading position and the bonding position.
Abstract:
A damping apparatus is provided for a positioning stage that is operative to move and position an object along a motion axis. The damping apparatus comprises a motion transformation device operative to rotate the positioning stage about a rotary axis that is substantially perpendicular to the motion axis, in response to forces generated to the positioning stage during acceleration or deceleration thereof. Resilient elements connected to the positioning stage serve to reduce transmission of vibration generated from the positioning stage.
Abstract:
A method of producing a leadframe is provided, the method including the steps of providing a substrate, plating the substrate with a layer of tin, plating a layer of nickel over the layer of tin, and thereafter plating one or more protective layers over the layer of nickel. The leadframe may thereafter be heated to produce one or more intermetallic layers comprising tin, which impedes the out-diffusion of copper from a base material of the leadframe to the surface thereof.
Abstract:
A tunable vibration absorption device is provided that is suitable for active or semi-active vibration absorption or damping of vibrations in vibrating structures. It comprises a stack including a force actuator mechanism for generating an axial actuation force and a force sensor mechanism which is responsive to an external force acting on the stack to generate a force signal. A controller unit is electrically connected to the force sensor mechanism for receiving the force signal generated by the force sensor mechanism, and it is also electrically connected to the force actuator mechanism for adjusting the axial actuation force generated by the force actuator mechanism in response to the received force signal generated by the force sensor mechanism.
Abstract:
A method of producing a leadframe is provided comprising the steps of providing a substrate, plating the substrate with a layer of tin, plating a layer of nickel over the layer of tin, and thereafter plating one or more protective layers over the layer of nickel. The leadframe may thereafter be heated to produce one or more intermetallic layers comprising tin, which impedes the out-diffusion of copper from a base material of the leadframe to the surface thereof.
Abstract:
The invention provides a pick and place assembly for transferring a film of material. The assembly comprises a collet having a substantially convex contact surface for contacting the film, the collet including a vacuum suction device operative to generate a force to hold the film. The film may comprise a thermoplastic adhesive tape or B-stage thermoset epoxy coated film.
Abstract:
The invention provides an apparatus and method for cleaning a plurality of electronic components. A tank is provided for containing a cleaning fluid and an ultrasonic resonator is mounted in communication with the cleaning fluid for charging ultrasonic energy thereto. A support platform positionable over a top surface of the cleaning fluid supports the electronic components such that the electronic components are in contact with said top surface of the cleaning fluid in use. Further, a cleaning fluid supply system is configured to generate a continuous flow of cleaning fluid into the tank for cleaning the electronic components in contact with said top surface of the cleaning fluid.
Abstract:
This invention concerns particulate reinforced Al-based composites, and the near net shape forming process of their components. The average size of the reinforced particle in the invented composites is 0.1–3.5 μm and the volume percentage is 10–40%, and a good interfacial bonding between the reinforced particulate and the matrix is formed with the reinforced particles uniformly distributed. The production method of its billet is to have the reinforced particles and Al-base alloy powder receive variable-speed high-energy ball-milling in the balling drum. Then, with addition of a liquid surfactant, the ball-mill proceeds to carry on ball-milling. After the ball-milling, the produced composite powder undergoes cold isostatic pressing and the subsequent vacuum sintering or vacuum hot-pressing to be shaped into a hot compressed billet, which in turn undergoes semisolid thixotropic forming and may be shaped into complex-shaped components. These components can be used in various fields. This product is featured with excellent property, good machinability, stable quality, component near net shape forming and cost effective and higher performance.