Some technical terms in the FPC industry

A

Accelerate Aging - The normal Aging process is accelerated using manual methods.

Acceptance Quality Level (AQL) -- Maximum acceptable number of defects in a batch of products, usually used in sampling planning.

Acceptance Test -- A Test to determine the acceptability of a product, to be determined between the customer and the supplier.

Access Hole -- A series of holes in a continuous layer of a multilayer circuit board that are centered in the same location and run to a surface of the circuit board.

Annulus Ring -- Retaining the conductor part around the hole.

Artwork -- Used for producing "Artwork Master", "production Master", with precise proportions of film.

Artwork Master -- Usually a film of precise proportions with a 1:1 pattern for producing a "Production Master".

B

Back Light -- backlight method is a magnifying visual inspection method to check whether the copper wall through the hole is intact or not. Its approach is to carefully thin the substrate outside the hole wall from a certain direction, and then use the principle of resin translucent, to shoot Light from behind. If the quality of chemical copper hole wall is intact without any holes or pinholes, the copper layer will be able to resist light and appear dark in the microscopic, once the copper wall has holes, there will be light points appear and be observed, and can be magnified photographic evidence, known as the backlight method, but only half a hole can be seen.

Base Material -- Insulating Material on which the circuit is formed. (It can be rigid or flexible, or a combination of both. It can be a non-conductive or insulating metal plate.) .

Base Material thickness -- The thickness of the Base Material, not including copper foil or coating.

Bland Via -- The through-hole extends only to one surface of the circuit board.

Blister -- A form of lamination which is a local uplift between two layers of the substrate or between the substrate and copper foil or between the protective layer.

Board thickness is the total thickness including the base material and all the conductive layer formed on it.

Bonding Layer - refers to the film Layer of a multilayer board.

C

C-staged Resin -- Resin in its final state of curing.

Chamfer (drill) -- The Angle at the end of the drill shank.

Impedance, the resistance of parallel wire structure to ac current, usually occurring at high speeds and usually consisting of constants over a frequency width range.

Circuit -- a certain number of electrical elements and devices capable of performing a desired electrical function.

Circuit Card -- See Printed Board.

"Circuitry Layer" -- the Circuitry board contains the wires including the ground surface and the voltage surface.

Circumferential Separation -- A crack or void along the entire circumference of a plating plate.

Creak -- crack, in the circuit board often refers to copper foil or through hole coating, in the heat stress test, often appear at all levels of part or all of the fracture.

Crease -- creases, in multilayer panels, that occur when copper is not handled properly.

Date Code - Period Code used to indicate when the product will be produced.

D

Delamination -- separation between substrate layers, between substrate and copper foil, or between all planes in the circuit board.

Delivered Panel(DP) -- One or more circuit boards are arranged in a certain way on a single board to facilitate assembly and testing of the next process.

Dent -- A Dent in the surface of a conductive copper foil that does not significantly affect the thickness of the foil.

Design spacing of depicting the distance between Conductive - line, or in the customer drawings on the definition of the distance between the lines.

Desmear -- Decontamination, removal of resin and drilling debris melted by drilling friction from the hole wall.

Dewetting -- You may have inherited electrical energy from melted tin that is either thick or thin, but not exposed.

Dimensioned Hole - A number of holes in a circuit board whose location is already defined by its Dimensioned size and not necessarily the same size as the grid.

Printed Board -- Double Side Printed Board

Drill body length -- The distance from the tip of the Drill to the point where the diameter of the Drill intersects the Angle of the shoulder.

E

Eyelet -- riveting eye, is a kind of bronze or brass hollow rivets, when a hole is found broken on the circuit board, you can add the riveting eye, not only can maintain the conductive function, but also can plug welding parts. However, due to the industry's strict requirements on the quality of the circuit board, the use of riveting eye is less and less.

F

Fiber Exposure refers to the fact that the surface of the substrate may lose the resin layer covered by it after being attacked by external mechanical friction and chemical reaction, and the glass cloth exposed to the substrate is called Fiber Exposure, and the hole wall is called Fiber protrusion.

Fiducial Mark - benchmark Mark, in order to downstream assembly on the board, convenient for its visual aid system operation, often in the large IC in the plate welding pad outer edge on the right and left each add a round or other shape of "benchmark Mark", to assist positioning machine.

Flair -- the shape distortion of the first side and the edge Angle distortion, which in the circuit board industry refers to the tip of the bit, the edge Angle distortion caused by the widening of the first side of the bit is caused by improper grinding of the bit, which is a minor defect of the bit.

Flammability Rate (Flammability rating) refers to the Flammability of the circuit board as determined by its Flammability after a pattern test has been performed in a predetermined procedure.

Flame Resistant -- Flame Resistant refers to the fact that in order to achieve a certain flammability grade (HB, VO, V1 and V2 in UL), certain chemicals (such as more than 20% bromo in FR-4) must be added to the formulation of the resin so that the board can achieve a certain Flame resistance. Generally, FR-4 will be printed with manufacturer's red UL watermark on the radial side of its substrate surface, while g-10 without flame retardant can only be printed with green watermark on the radial side.

Flare - fan-shaped collapse, in mechanical punching, often due to the poor mold or plate embrittlement, or the wrong punching conditions, resulting in the collapse of the hole plate, the formation of abnormal fan bell, known as the fan-shaped collapse.

Flashover -- Flashover, on the circuit board, between two conductor lines (even if there is welding resistance green paint), when there is a voltage, the surface of the insulating material between the generation of a "disruptive discharge", called "Flashover".

Flexible Printed Circuit,FPC -- Flexible Printed Circuit board (FPC) is a special type of Printed Circuit board that can be assembled with three-dimensional shape changes and is based on Flexible polyacrylamide (PI) or polyester (PE). The soft plate may also be plated through holes or surface-mounted like a hard plate.

Flexural Strength -- Flexural Strength, the PCB base material plate, take its width one inch, length 2.5--6 inches (according to the thickness of the different) of the sample, at both ends of the bottom each place a support point, in the central point of continuous pressure, until the sample fracture. The minimum pressure required to break it is called flexural strength. It is one of the important mechanical properties of hard circuit board.

Flute -- A Flute is the Flute part hollowed out in the cylinder of a drill tip or gong knife that can be used for the withdrawal of waste chips.

Flux -- Flux resistance, is a chemical active at high temperature, can be welded to the surface of the oxide or dirt to remove, so that the molten solder can be combined with the clean underlying metal and complete the welding.

GAP -- the first side apportionment and the long edge disconnection refers to the separation of the two first sides of the drill tip, which is caused by poor grinding and is also a minor defect of the drill tip.

G

Gerber Data, GerBerFile, is a series of complete software files (officially named "RS 274") developed by Gerber corporation for circuit board graphics and hole positions, which can be used by circuit board designers or circuit board manufacturers to achieve file exchange.

Grid -- standard Grid, refers to the basic Grid Grid of circuit board wiring, the early length and width of each Grid is 100mil, that is based on IC pins for reference, the current Grid distance is more and more close.

Ground Plane -- Ground Plane, is a kind of board of multilayer board, usually a layer of line layer of multilayer board to match a layer of large copper surface Ground layer, as many parts of the public grounding return, shelter, and heat dissipation.

Grand Plane Clearance -- The ground Clearance ring, the ground or voltage pin of the component and its ground or voltage layer are usually connected to the large copper surface outside in a "tile-bridge" or "cross pin". As for the through-hole through which the layer is not connected to the large copper surface at all, any bridge must be removed and isolated from the outside world. In order to avoid deformation due to heat, the expansion space required by expansion must be set aside between the through hole and the large copper surface, which is the hollow ring of the ground.

H

Haloing -- White circle, white border. Usually when the board substrate plate in drilling, slotting and other mechanical processing is too fierce, resulting in the internal resin rupture or tiny cracking phenomenon.

Hay wire, also called Jumper wire. -- Is a printed circuit board that has been disconnected, or that needs to be welded and connected with painted wire outside the surface of the board because of a design error.

Heat Sink Plane -- Heat Sink Plane In order to reduce the heat of the circuit board, usually in addition to the group of parts, add a layer of aluminum plate has many foot holes.

A Hipot Test -- High Postential Test is an electrical Test performed at a higher DC voltage than is actually used to detect a large amount of current leakage

Hook -- The cutting edge is not straight. The drill tip part of the drill tip is composed of four surfaces, two of which are the first side for cutting function and two of which are the second side for supporting the first side. The leading edge of the first side is the cutting edge. The correct cutting edge should be straight. Improper grinding will make the cutting edge into a curved shape that is wide on the outside and narrow on the inside, which is a minor defect of the drill tip.

Hole Breakout -- to break a Hole. It means that part of the hole body has fallen outside the welding ring area, so that the hole wall is not completely surrounded by the welding ring.

Hole location -- The central location of a Hole.

Hole pull Strength -- Refers to the force that pulls the entire Hole wall off the board, i.e. the fixed force between the Hole wall and the board.

Hole Void -- Hole, refers to the Hole in the Hole wall has been completed to see the substrate Hole.

Hot Air Leveling -- called tin Leveling. A plate coated with tin from a tin oven is blown away by hot air under high pressure.

Hybrid Integrated Circuit -- It is a kind of Circuit applying precious metal conductive ink in printing mode on small porcelain thin plate, and then burning the organic matter in the ink at high temperature, leaving conductor Circuit on the board, and can weld the surface bonded parts.

i.

Icicle -- Solder tip refers to the pyramidal Solder that appears on the Solder surface of the assembly plate after wave soldering, also known as Solder Projection.

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