摘要 |
<p>An apparatus for and a process of batch assembly of sundry leaded or padded devices, encapsulated and non-encapsulated, onto a printed wiring board (PWB), which exhibit significant improvements in both manufacturability and reliability. A pressure frame assembly apparatus (11) permits an application of uniformly distributed pressures to a variety of leaded packages and padded semiconductor chips during cure of conductive adhesives (AdCons), and leads to the reduction of variations in initial interconnection resistance, and thereby to the enhancement of the reliability of AdCon interconnections. The pressures are applied to the devices by an external application of a fluid under pressure to a flexible, resiliently stretchable membrane (14) which conformably envelops outlines of the devices and adjacent areas of the PWB. Application of vacuum suction to within the cavity, formed by the pressure frame and the membrane (14), prior to the external application of the fluid pressure to the membrane, further improving the reliability of surface mounted assembly of packages on the interconnection board. Assembly yields approaching 100% were observed for a variety of surface mounted packages indicating that the system will be highly reliable. <IMAGE></p> |