Types: * [[carrier:smt|Surface mount technology (SMT)]] * [[carrier:th|Through hole]] ====== Generic terms and special packaging ====== ===== CERPACK ===== Ceramic package ===== COB (Chip-On-Board) ===== {{gallery>:image:chip_on_board.jpg}} Bare silicon chip without a package and affixed directly to the circuit board. Use in cost sensitive (ie cheap) applications. Above is probably from a commodity wrist watch. There seem to be two types: * Epoxy blob (below type): die is placed on board, bonded, and then covered with a blob of epoxy. The most common type * Upside down dies (above type): likely WLCSP with underfill. Basically a BGA where there is no encapsulant on the die and solder balls are attached directly to bond pads (see BGA below for example of this sort of thing) * Flexible circuit: these are common in the line drivers on LCD screens Example showing wire bonding to PCB: {{gallery>:mcmaster:cob.jpg}} ===== COF (Chip-On-Flex) ===== A variation of COB, where a chip is mounted directly to a flex circuit ===== COG (Chip-On-Glass) ===== A variation of COB, where a chip is mounted directly to a piece of glass - typically an LCD ===== CSP (Chip Scale Package) ===== Package no more than 1.2x the size of the silicon chip. ===== LTCC (Low Temperature Co-fired Ceramic) ===== ??? ===== MCM (Multi-Chip Module) ===== {{:mcmaster:carrier:mcm_sw206.jpg?300|}} Several dies integrated into one package. Considerable variety. ===== Flip chip ===== A package where the die is mounted upside down. Usually this implies BGA or similar package. ==== Ceramic BGA example ==== Had thermal paste to improve conductivity: {{:carrier:xpc7455:package_pasted.jpg?300}} After cleaning: {{:carrier:xpc7455:package_clean.jpg?300}} When most solder balls are removed on the bottom looks like this: {{:carrier:xpc7455:package_bot.jpg?300}} After dissolving some of the epoxy on the top: {{:carrier:xpc7455:package_some_top.jpg?300}} {{:carrier:xpc7455:package_some_side.jpg?300}} As can see in above though there was still some underfill left. Next pictures show the epoxy/underfill not completley dissolved and some gunk (solder paste?) left in the center as well as some sort of spacer: {{:carrier:xpc7455:package_some_nodie.jpg?300}} {{:carrier:xpc7455:package_some_ga.jpg?300}} {{:carrier:xpc7455:die_some.jpg?300}} {{:carrier:xpc7455:die_some_closeup.jpg?300}} ===== MICROARRAY ===== Usually refers to a chip for testing DNA ===== TCSP (True Chip Size Package), TDSP (True Die Size Package) ===== Package is the same size as silicon. ====== References ====== * http://en.wikipedia.org/wiki/Chip_carrier * http://en.wikipedia.org/wiki/List_of_integrated_circuit_packaging_types