| Common Terms used in PCB
Manufacturing |
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| To assist in understanding PCB terminology this is a list of
common PCB terms. For a more detailed glossary of terms please visit our PCB
glossary. |
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| Anti-Tarnish
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| A post-dip chemical process used to retard oxidation of
copper circuits.
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| Backup Material
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| Hard flat material used to back-up laminate when drilling to
reduce burrs.
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| Backplane
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| A very thick, large circuit board used to hold an array of
pins for wire wrapping.
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| Blanking Die
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| Using a die punch to “blank out” the finished circuit board,
used mostly for single-sided panels.
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| Blow Holes
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| Blow holes caused by an outburst of gas from solder fillet on
a circuit board during the soldering operation.
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| C-Stage
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| Fully-cured dielectric laminate.
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| Caul Plates
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| Rigid, polished, flat, stable steel plates used when pressing
or laminating MLBs.
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| Clad
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| A condition of the base material to which a relatively thin
layer or a sheet of metal foil has been bonded to one or both of its sides.
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| Conversion Coating
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| Anti-oxidant treatment applied to raw vendor foil.
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| DES
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| Develop, etch & strip process used in the etching stage
of inner-layer fabrication.
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| Direct Plate
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| Application of conductive coatings on drilled holes to
provide electrical continuity for electrolytic plating.
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| DOE
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| Design of experiments… a formal method of designing an
interactive test matrix.
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| Dog Bone
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| A plating defect found in drilled holes where the
electroplated copper is thin in the center and thicker at the knee.
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| Double Treat
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| Brass-based coating applied to copper foil as a substitute
for oxide.
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| Entry Material
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| Thin metal foil (usually aluminum) attached to top side of
drill stack to reduce drilling burrs and cool drill.
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| FPPY
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| First pass panel yield… number of good “panels” after
subtracting defective panels.
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| Flux
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| A chemical activator use when reflowing solder or attaching
components.
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| Haloing
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| Fracturing/delamination on or below the surface of the base
material; it is usually exhibited by a light area around holes.
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| Hard Board
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| Rigid circuit board.
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| Liquid Resist
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| The liquid form of photoresist used in the fabrication of
circuits.
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| Mil Spec
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| Specification set forth by the military.
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| Mil
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| Common term used to define thicknesses below 0.100 inches.
(One mil = 0.001 inches).
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| Millionths
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| Term used when defining thickness. (100 millionths = 0.0001
inches.)
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| Mother Board
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| A
printed circuit board
used for interconnecting arrays of plug-in electronic modules.
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| Nail Heading
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| The flared condition of copper on the innerconnect layer of a
multilayer caused by poor drilling.
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| One Ounce Oil
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| Weight of 1 square foot of copper foil. (1 oz = 0.00134
inches, ½ oz = 0.0007 inches, etc.)
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| OSHA
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| Occupational Safety & Health Agency.
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| OSP
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| Organic Surface Protection.
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| Oxide
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| A special treatment applied to copper surfaces of inner
layers of a PWB to insure bond integrity.
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| Panel
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| Used to describe a common sheet size used in the fabrication
process, ie: 24” X 18”.
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| Panel ft (Laminate ft)
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| A laminate area measurement, one-side only of the panel. (1
panel, 18” X 24” X 1 side = 3 panel ft).
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| Pattern-Plate
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| Electroplating of circuits using photoresist as a mask to
protect the background, usually copper & tin.
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| Photoresist
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| An organic emulsion containing photoactive compounds, which
will crosslink when exposed to UV light.
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| Pin Holes
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| Small defects etched through a circuit pattern.
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| Pink Ring
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| A defect caused by poor bonding around drilled holes
displayed by acid attack of the oxide.
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| Pitch (density)
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| A method of defining circuit lines and spaces i.e.; 4 &
4, 4 mil lines and 4 mil spaces.
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| Plasma
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| Creation of corona in a chamber by exciting certain gasses in
a partial vacuum with an electrical field, used to desmear.
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| Power Plane
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| Heavy circuit features designed to carry high electrical
loads in a PWB.
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| Print
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| Expose step to define circuit patterns in photo resist.
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| Print & Etch
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| Simple fabrication method using photoresist to define etch
pattern.
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| Pumice Scrub
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| A mechanical cleaning step using brushes and an abrasive
media.
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| Punching
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| Using dies to punch component holes, usually in single &
double-sided PWBs.
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| Signal Layer
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| Fine circuits designed to carry high speed signals throughout
a circuit board and its components.
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| Skip Plate
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| Area of absent metal in plating.
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| Solder Plate
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| Tin/lead alloy plated in a pattern to define the finished
features or circuits.
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| SPC
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| Statistical Process Control.
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| Surface ft
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| Total surface square feet area of a given work piece. (1
panel 18” X 24” X 2 sides = 6 surface ft).
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| Tab Plate
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| Selective plating on edge connectors, usually nickel/gold.
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| Tabs
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| A portion of a conductive pattern formed by printing, serving
as one part of a contact system.
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| Tenting
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| A printed circuit board fabrication method of capping
plated-through holes and the surrounding conductive pattern with a dry film
resist.
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| Thin Core
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| Thin laminate, usually less than 0.005 inches thick.
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| Wedge voids
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| A layer separation defect in a drilled hole which are sites
for retention of process chemicals.
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