Abstract: The invention provides a method and apparatus for aligning a substrate. The apparatus comprises a ball pick head for picking up a plurality of solder balls in a ball pick-up process and depositing them onto the substrate, and a vision system adapted to view and obtain positional information of the substrate. Furthermore, a carrier is provided to which the vision system is mountable, such that operation of the vision system is decoupled from movement of the ball pick head. Drivers responsive to said positional information viewed by the vision system are operative to align at least the substrate and the ball pick head for depositing solder balls onto the substrate.

Abstract: The invention provides a method and apparatus for aligning a substrate. The apparatus comprises a ball pick head for picking up a plurality of solder balls in a ball pick-up process and depositing them onto the substrate, and a vision system adapted to view and obtain positional information of the substrate. Furthermore, a carrier is provided to which the vision system is mountable, such that operation of the vision system is decoupled from movement of the ball pick head. Drivers responsive to said positional information viewed by the vision system are operative to align at least the substrate and the ball pick head for depositing solder balls onto the substrate.

Abstract: The invention provides an apparatus and method for the application of adhesive substances to objects, such as solder balls, for the purpose of mounting them onto substrates. The apparatus comprises an applicator having a layer of the adhesive substance and a pick carrier to carry objects and move the objects from a supply source to a substrate for mounting the objects thereon. The applicator is located so that the applicator applies the adhesive substance to the objects while the objects carried on the pick carrier are moving between the supply source and the substrate.

Abstract: There is disclosed a method and apparatus for ensuring release of objects such as solder balls from a pick head in a transfer and placement apparatus, comprising causing said pick head to vibrate by applying a vibration signal to said pick head over a range of frequencies. The range of frequencies is chosen such that it bounds the resonant frequencies of the pick head which may be calculated by computer simulation.

Abstract: A solder reflow oven for the processing of ball grid array substrates bearing solder balls is described, comprising: input means for introducing substrates into the oven, a processing chamber within which the substrates are subject to a solder reflow process, and output means for discharging substrates from the oven for further processing or handling, and means for transferring the substrates through the processing chamber in a first direction towards the output means. The processing chamber comprises a plurality of heating and cooling zones arranged with a constant pitch in the first direction, and the transferring means is adapted to move the substrates in the first direction in stages, with each component moving a distance equal to the pitch between two zones in each stage, whereby the components are moved from zone to zone in stages.