IMPACT OF ADVANCED SURFACE MOUNT PACKAGES ON SMT MANUFACTURING PROCESS

摘要

The major tendency of surface mount components is the reduction of the non-electronic elements. Component lead frames, plastic body, carrier packages, etc. are decreasing in size to increase the I/O to surface area ratio as well as to reduce overall component height. Components such as Direct Chip Attach (DCA), Chip On Board (COB) and mini ball grid array virtually eliminate second level packaging (beyond bare die). The tendency for the reduction/elimination of the non-electronic functional elements of components has introduced new challenges for component manufacturers as well as for bare board manufacturers and PCB assemblers.The diversity of component types influences process sequences, process materials, manufacturing equipment, and skill requirements of the people involved in the manufacture of electronic products. Also, a great deal of effort is being expended to develop multiple technology assembly processes for a given product. For the purpose of this paper various Ball Grid Array (BGA) technologies, DCA (flip chip), "standard" surface mount components, and TAB are considered. Each assembly process has its own unique requirements. However, to take full advantage of these technologies for leading edge electronic products, they must in some cases be processed together on a single PCB assembly.This paper discusses trends in electronics packaging and processes relative to surface mount technology devices. This discussion involves process materials, and process techniques with a primary focus on solder joint attached componentry.