IPC-T-50F_.pdf.pdf - 第67页
Slump 73.0951 The distance of a substance, e.g., adhesive, moves after it has been applied and cured. Smaller-the-Better Characteristic 91.1817 A parameter of quality that improves performance as its value decreases. (Se…
Shielding, Electronic 21.1527
A physical barrier, that is usually electrically conductive,
that reduces the interaction of electric or magnetic fields
upon devices, circuits, or portions of circuits.
Short, Electrical (n.) 92.1301
A fault that causes to be connected two or more points that
are normally electrically separated.
Short-Term Capability 91.1302
The capability of a process that exhibits statistical control
over a brief period of time.
Shoulder Angle 51.0929
The angle of the blended transition from the drill shank
diameter to the drill body diameter.
Shuttle 44.0930
The device that holds the quill of the filling yarn and car-
ries it back and forth across the width of the fabric.
Sigma (ς) 94.0931
The lowercase Greek letter that is used to designate a stan-
dard deviation of a population.
Signal 21.0932
An electrical impulse of a predetermined voltage, current,
polarity and pulse width.
Signal Conductor 22.0934
An individual conductor that is used to transmit an
impressed electrical signal.
Signal Line 22.0935
A conductor used to transmit a logic signal from one part
of a circuit to another.
Signal Plane 22.0936
A conductor layer that carries electrical signals. (See also
‘‘Ground Plane’’ and ‘‘Voltage Plane.’’)
Signal-to-Noise Ratio (Process Control) 91.0933
A response variable that takes into consideration both
parameter mean and parameter variation values.
Silkscreening 52.0937
see ‘‘Screen Printing.’’
Silver Migration 92.0938
The ionic removal of silver and its redeposition in an adja-
cent area under the influence of migration-inducing condi-
tions.
Simulated Aging 92.0939
The artificial exposure of material to conditions of both
high and low temperature and humidity in an attempt to
produce changes that occur during its extended exposure to
normal environmental conditions.
Simulated Datum 92.0940
The surface or feature(s) on a fixture, used as a machine
reference, which is correlated to the original board or
assembly datum
Single-Image Production Master 24.0941
A production master that is used in the process of making
only one printed board. (See also ‘‘Multiple-Image Produc-
tion Master.’’)
Single-Inline Package (SIP) 31.0942
A component package with one straight row of pins or wire
leads.
Single-Layer Carrier Tape 36.1528
The carrier for conductors used in tape-automated bonding
that consists only of a metal foil. (See also ‘‘Multilayer
Carrier Tape,’’ ‘‘Two-Layer Carrier Tape,’’ and ‘‘Three-
Layer Carrier Tape.’’)
Single-Point Bonding 74.0943
The making of terminations one at a time. (See also ‘‘Gang
Bonding.’’)
Single-Sided Assembly 80.0944
A packaging and interconnecting structure with compo-
nents mounted only on one side. (See also ‘‘Double-Sided
Assembly.’’)
Single-Sided Printed Board 60.0945
A printed board with a conductive pattern on only one side.
Sizing 44.0948
The method of applying size i.e. starch to a group (width)
of warp yarns on a continuous basis.
Skin Effect 21.0946
The increase in resistance of a conductor at microwave fre-
quencies that is caused by the tendency of electric current
to concentrate at the conductor’s surface.
Skipping 52.0947
When a coating or resist does not cover the spaces between
adjacent conductors.
Slice 35.0949
see ‘‘Wafer.’’
Sliver 96.0950
A slender portion of plating overhang that is partially or
completely separated from a conductor edge.
IPC-T-50F June 1996
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Slump 73.0951
The distance of a substance, e.g., adhesive, moves after it
has been applied and cured.
Smaller-the-Better Characteristic 91.1817
A parameter of quality that improves performance as its
value decreases. (See also ‘‘Larger-the-Better Characteris-
tic’’ and ‘‘Nominal-is-Best Characteristic’’).
Smear Removal 54.0953
see ‘‘Desmear.’’
Smeared Bond 74.0952
A bond impression that has been distorted or enlarged by
excess lateral movement of the bonding tool or holding
device fixture.
Socket Contact 37.0954
A female connector contact.
Solarization 24.0955
A decrease in density with increased exposure.
Solder 46.0956
A metal alloy with a melting temperature that is below
427-deg.C (800-deg.F).
Solder Ball 75.0959
A small sphere of solder adhering to a laminate, resist, or
conductor surface. (This generally occurs after wave solder
or reflow soldering.)
Solder Bath 75.1767
A container or vessel of molten solder into which compo-
nent parts or assemblies are immersed.
Solder Bridging 75.0960
The unwanted formation of a conductive path of solder
between conductors.
Solder Bump 74.0961
A round ball of solder used to make interconnections
between a flip-chip component and a base material during
controlled-collapse soldering.
Solder Coat 53.0962
A layer of solder that is applied directly from a molten sol-
der bath to a conductive pattern.
Solder Connection 75.0963
An electrical/mechanical connection that employs solder
for the joining of two or more metal surfaces. (See also
‘‘Cold Solder Connection,’’ ‘‘Disturbed Solder Connec-
tion,’’ ‘‘Excess Solder Connection,’’ ‘‘Insufficient Solder
Connection,’’ ‘‘Overheated Solder Connection,’’ ‘‘Preferred
Solder Connection,’’ ‘‘Rosin Solder Connection.’’
Solder Connection Pinhole 75.0964
A small hole that penetrates from the surface of a solder
connection to a void of indeterminate size within the sol-
der connection.
Solder Cream 46.0965
see ‘‘Solder Paste.’’
Solder Embrittlement 75.0966
The reduction in mechanical properties of a metal as a
result of local penetration of solder along grain boundaries.
Solder Fillet 75.0967
A normally concave surface of solder that is at the intersec-
tion of the metal surfaces of a solder connection.
Solder Levelling 53.1677
A solder coating process that causes redistribution and/or
partial removal of excess molted solder from a printed
board by applying sufficient heat and mechanical force.
Solder Mask 47.0973
see ‘‘Solder Resist.’’
Solder Meniscus 75.1766
The contour of a solder shape that is the result of the
surface-tension forces that take place during wetting.
Solder Paste 46.1818
Finely divided particles of solder, with additives to pro-
mote wetting and to control viscosity, tackiness, slumping,
drying rate, etc, that are suspended in a cream flux.
Solder-Paste Flux 75.0957
Solder paste without the solder particles.
Solder Plug 75.0974
A core of solder in a plated-through hole.
Solder Projection 75.0975
An undesirable protrusion of solder from a solidified solder
joint or coating.
Solder Resist 47.1674
A heat-resisting coating material applied to selected areas
to prevent the deposition of solder upon those areas during
subsequent soldering.
Solder Resist Aperture 22.0977
An opening in a solder resist.
Solder Side 22.0978
The secondary side of a single-sided assembly.
June 1996 IPC-T-50F
63
Solder Spread Test 92.1819
The determination of a relative measure of solder flux effi-
ciency that is obtained by determining the area of spread of
a specified weight of solder that has been placed on a spe-
cially prepared and fluxed metallic surface.
Solder Sputter 75.0979
Extraneous fragments of solder with an irregular-shape.
Solder Terminal 37.0980
An electrical/mechanical connection device that is used to
terminate a discrete wire or wires by soldering. (See also
‘‘Bifurcated Solder Terminal,’’ ‘‘Cup Solder Terminal,’’
‘‘Hook Solder Terminal,’’ ‘‘Perforated (Pierced) Solder
Terminal,’’ and ‘‘Turret Solder Terminal.’’)
Solder Webbing 75.0981
A continuous film or curtain of solder that is parallel to, but
not necessarily adhering to, a surface that should be free of
solder.
Solder Wicking 75.0982
The capillary movement of solder between metal surfaces,
such as strands of wire.
Solderability 75.0958
The ability of a metal to be wetted by molten solder.
Soldering 75.0968
The joining of metallic surfaces with solder and without
the melting of the base material.
Soldering Flux 75.0970
see ‘‘Flux.’’
Soldering Iron 75.1768
Common name for a tool which is used to heat components
and to reflow solder.
Soldering Iron Tip 75.0971
The portion of a soldering iron that is used for the applica-
tion of the the heat that melts the solder.
Soldering Oil (Blanket) 75.1529
Liquid formulations that are used in intermix wave solder-
ing and as coverings on static and wave soldering pots in
order to eliminate dross and to reduce surface tension dur-
ing the soldering operation.
Soldering-Ability 75.0969
The ability of a specific combination of components to
facilitate the formation of a proper solder joint.
Solderless Wrap 75.1530
The connecting of a solid wire to a square, rectangular, or
V-shaped terminal by tightly wrapping a solid-conductor
wire around the terminal with a special tool.
Solid-State Bond 74.0983
see ‘‘Diffusion Bond.’’
Solid-Tantalum Chip Component 32.0984
A capacitor in a leadless package whose dielectric material
is solid tantalum.
Solvent 76.0985
A non-reactive liquid substance that is capable of dissolv-
ing another substance.
Solvent Cleaning 76.0986
The removal of organic and inorganic soils using a blend
of polar and nonpolar organic solvents.
Solvent Extraction 76.1531
The removal of one or more components from a liquid
mixture by intimate contact with a second liquid that is
nearly insoluble in the first liquid and which dissolves the
impurities and not the substance that is to be purified.
Solvent Pop 76.0987
Blistering caused by entrapped solvent.
Solvent Release 76.0988
The ability to permit solvents to evaporate.
Solvent Wash 76.0989
see ‘‘Solvent Cleaning.’’
Spacing 22.0990
see ‘‘Center-to-Center Spacing,’’ ‘‘Conductor Spacing,’’
‘‘Edge Spacing,’’ and ‘‘Pitch.’’
Spade Contact 37.0992
A type of male connector contact that consists of flat metal
that mates with a fork contact.
Spalling 97.0993
The chipping, fragmenting or separation of a surface coat-
ing, or the cracking, breaking or splintering of materials,
due to heat.
Span 22.0994
The distance from the reference edge of the first conductor
in a group of parallel conductors to the reference edge of
the last conductor in the group.
Special Cause 91.0995
A source of variation that is intermittent, unpredictable, or
unstable that affects only some of the individual values of
process output.
Specific Solderability 75.0997
The ease with which a metal or alloy can be wetted under
specific conditions.
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