Rework of High-Density Modules

With advancements in MCMs, where large chips (up to 500-mils square) are closely packed and where devices and interconnect substrates are fragile (for example, polyimide thin-film multilayer substrates used in MCM-D), new rework challenges have arisen. In these high-density circuits, spacings between the chips may be as small as 40 mils—too small 

Components that are attaehed with thermoplastic adhesives are easiest to remove Parts to be removed are simply heated with a hot solder iron 

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