IPC-T-50F_.pdf.pdf - 第65页
Semiconductor Carrier 74.1290 A package for semiconductor die. Sensitivity Control 91.1519 The provisions that allow a machine to be set to acceptance and rejection thresholds that correspond to the end-use requirements …
Saponifier 76.1276
An aqueous organic- or inorganic-base solution with addi-
tives that promote the removal of rosin and/or water-
soluble flux.
Satin Weave 44.1516
A fabric configuration where the surface is almost entirely
made up of warp filling adjacent yarns, thereby producing
a smooth surface. (The intersection points do not fall in a
straight diagonal, or twill, but in a patterned formation.)
Scalar Processing 11.1277
The use of a computer architecture in which single opera-
tions are performed on data elements.
Scan Rate 92.0755
The rate at which a machine scans the surface of the unit
being evaluated, expressed in surface area per unit of time
or time per unit area of surface.
Scan-Dead Time 92.1278
The time during a scanning process when data is not being
collected from the unit being evaluated.
Scanner, Test 92.0693
A program controlled relay matrix used for connecting any
unit-under-test circuit mode to the analog instrument bus.
Scatter Diagram 94.0991
A graph that depicts the relationships between an indepen-
dent variable and a dependent response variable.
Schematic Diagram 26.1107
A drawing that shows, by means of graphic symbols, the
electrical connections, components and functions of a spe-
cific circuit arrangement.
Scoop-Proof Connectors 37.1239
Connectors that incorporate features that prevent contact
damage during mating and unmating.
Scratch 92.1203
A narrow furrow or groove in a surface. (It is usually shal-
low and caused by the marking or rasping of the surface
with a pointed or sharp object.)
Screen Printing 52.1204
The transferring of an image to a surface by forcing a suit-
able media with a squeegee through an imaged-screen
mesh.
Scribe Coat 24.1205
A stable base material, such as glass or film, with an
opaque coating.
Scribing 24.1279
The cutting of the opaque coating, but not the base mate-
rial, on a scribe-coat material.
Scrubbing 74.1280
The rubbing of the lead wire and bonding land in order to
break up oxide layers and to improve bondability.
Search Height 74.1281
The height of a bonding tool above the bonding area prior
to it being lowered to make the termination.
Second Bond 74.1283
The second termination in a sequence of bonds made to
form a conductive path. (See also ‘‘First Bond.’’)
Secondary Relief 51.1282
The clearance angle that is behind the primary relief of a
drill point.
Secondary Side 22.1517
That side of a packaging and interconnecting structure that
is opposite the primary side. (It is the same as the ‘‘solder
side’’ on through-hole mounting technology.)
Section Beam 44.1284
A flanged cylinder onto which yarn is drawn and accumu-
lated from the yarn bobbins or packages.
Sectional Specification (SS) 26.1783
A document that describes the specific requirements per-
taining to a portion of a set, family, or group of products,
materials or, services.
Seed Layer 53.1286
see ‘‘Activating Layer.’’
Seeding 53.1285
see ‘‘Activating.’’
Self Test 92.1287
The ability of an analyzer to appraise itself prior to per-
forming a test procedure.
Selvage 44.1288
The edge of the fabric where the body of the fabric ends as
defined by the last warp yarn.
Semi-Additive Process 53.1518
An additive process wherein the entire thickness of
electrically- isolated conductors is obtained by the com-
bined use of electroless metal deposition and electroplat-
ing, etching, or both. (See also ‘‘Fully- Additive Process.’’)
Semiconductor 30.1289
A solid material, such as silicon, that has a resistivity that
is midway between that of a conductor and of a resistor.
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Semiconductor Carrier 74.1290
A package for semiconductor die.
Sensitivity Control 91.1519
The provisions that allow a machine to be set to acceptance
and rejection thresholds that correspond to the end-use
requirements for the units being evaluated.
Sensitizing 53.1291
see ‘‘Activating.’’
Separable Component Part 30.1520
A replaceable component part with a body that is not
chemically bonded, excluding protective coatings, solder,
and potting compounds, to the base material.
Sequentially-Laminated Multilayer Printed Board
61.1521
A multilayer printed board that is formed by laminating
together through-hole plated double-sided or multilayer
boards. (Thus, some of its conductive layers are intercon-
nected with blind or buried vias.)
Serpentine Cut 77.1293
A trimming cut in a film component in the shape of an
wavy (serpentine) pattern.
Set-Up Time 92.1522
The time required to change hardware and software, to
set-up necessary windows, and to run calibration and veri-
fication tests in order to ensure that a system is ready for
operation.
Shadowing, Etchback 54.1294
A condition that occurs during an etchback process in
which the dielectric material immediately next to the foil is
not removed completely. (See Figure S-1.) (This can occur
even though an acceptable amount of etchback may have
been achieved elsewhere.)
Shadowless Illumination 24.1523
The illumination of the area of interest by the light source
of a magnifying device so that no shadows fall on the area
of interest from objects in the field of view that are not of
prime interest.
Shank 51.1295
The cylindrical part of a drill that is held in the spindle of
a drilling machine.
Shank Diameter 51.1297
The actual size of a drill shank.
Shank-to-Drill Body Concentricity 51.1296
The total variation of the location of the outside diameter
of a rotating drill shank.
Shear Strength 92.1298
The force required to shear apart adhesive-bonded (and
cured) materials and/or components. (See also ‘‘Lap Shear
Strength’’ and ‘‘Torsional Strength.’’)
Shear Test 92.1765
The maximum stress a material can withstand in shear; the
value of the force achieved when shearing stress is applied
to a solder joint or wire bond to determine the breaking
load.
Sheet Capacitance 92.1524
The electrical capacitance of a material as measured from
one electrode to another, expressed in a unit of capacitance
(e.g. farads or microfarads) per unit area.
Sheet Resistance 92.1525
The electrical resistance of a planar film of a resistive
material with uniform thickness as measured across oppo-
site sides of a unit square pattern, expressed in ohms per
square.
Sheet-Metal Contact 37.1299
A type of connector contact that consists of flat spring
metal that has been formed by either stamping or bending.
(See also ‘‘Machined Contact’’)
Shelf Life 90.1526
The length of time a material, substance, or product can be
stored, under specific environmental conditions, while it
meets all applicable specification requirements and remains
suitable for its intended use.
Shield (n.) 21.1300
The material around a conductor or group of conductors
that limits electromagnetic and/or electrostatic interference.
IPC-I-002323
Figure S–1 Shadowing
Shadowing
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Shadowing
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Shadowing
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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.
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