... criteria is the presence of orientation marks within the boundary of board. These marks could be the board reference so long as it cannot | MULTILAYER CIRCUITS PLANT | be read from the other side. (This is for your protection to prevent the boards made inside out). Images should comply with design rules that | MULTILAYER CIRCUITS PLANT | will result in a board that will meet performance and cost requirements. - Scale must be given, tapes securely stuck to the backing sheet, track | MULTILAYER CIRCUITS PLANT | to pad & track to track joints complete and the backing sheet clean. - Scale must be given and be at least 2:1. Plots must | MULTILAYER CIRCUITS PLANT | also offer sharp edge definition and traces dense enough for blocking light when photographing. - Preferred on 7mil (178mm) thick base for stability. Films should | MULTILAYER CIRCUITS PLANT | be plotted on laser photoplotter or on vector photoplotter using a minimum resolution of ½mil (13mm). - Preferred in Gerber® format although accepted in other | MULTILAYER CIRCUITS PLANT | formats. (Refer to CID-014 for information on Documentation in Digital Form). - files are the only acceptable form of ...
[ Multilayer Circuits Plant ]


... BOARDS | | WAVE SOLDERING | A process wherein printed boards are brought in contact with a gently overflowing wave of liquid solder which | MULTILAYER CIRCUITS PLANT | is circulated by a pump in an appropriately designed solder pot reservoir. The prime functions of the molten wave are to serve as a heat | MULTILAYER CIRCUITS PLANT | source and heat transfer medium and to supply solder to the joint areas. | WEBBING | Unwanted threadlike deposits of solder on insulated areas. | | MULTILAYER CIRCUITS PLANT | WETTING | The formation of a relatively uniform, smooth, unbroken, and adherent film of solder to a base material immediately upon contact. | WIRE-BONDING | | MULTILAYER CIRCUITS PLANT | Connecting technique using thin metal wire connections between a component and the ...
[ Multilayer Circuits Plant ]


... panels are then dried in preparation for electroless copper deposition. The scrubbing line is equipped with an automatic loader and unloader and may be | MULTILAYER CIRCUITS PLANT | run unattended Alkaline Permanganate: Smear Removal Before direct metallization, the drilled holes on multilayers have to be desmeared. The main purpose of this treatment is | MULTILAYER CIRCUITS PLANT | to remove any epoxy smeared onto the edge of the inner layer copper pads whilst drilling. The smear is the result of a hot drill | MULTILAYER CIRCUITS PLANT | melting the epoxy resin and spreading it across the hole wall during its up and down motion. The epoxy smear causes poor and in some | MULTILAYER CIRCUITS PLANT | cases non electrical continuity to the innerlayers as well as poor adhesion of the plated copper to the hole wall. In desmear, the chemical attack | MULTILAYER CIRCUITS PLANT | is designed to remove only the surface smear of resin from the hole wall, without attacking the wall structure itself. For most needs desmearing is | MULTILAYER CIRCUITS PLANT | sufficient whilst for some military applications it is necessary to etchback 75mm for what is referred to as 3 ...
[ Multilayer Circuits Plant ]