IPC-D-859.pdf - 第10页

Film Single or multiple layers of coatings of thin or thick material used to form various elements (resistors, capaci- tors, inductors) or interconnections and crossovers (con- ductors, insulators). Thick ﬁlms are deposi…

Bond envelope The range of bonding parameters over

which acceptable bonds may be formed.

Bond interface The interface between the lead and the

material to which it was bonded on the substrate.

Bond lift-off The failure mode whereby the bonded lead

separates from the surface to which it was bonded.

Bond off See Bond lift-off.

Bond land See Bonding area.

Bond schedule The values of the bonding machine

parameters used when adjusting for bonding. For example,

in ultrasonic bonding, the values of the bonding force,

time, and ultrasonic power.

Bond separation The distance between the attachment

point of the ﬁrst and second bonds of a wire bond.

Bond site The portion of the bonding areas where the

actual bonding took place (see Bonding area).

Bond strength In wire bonding, the pull force at rupture

of the bond interface measured in the unit gram-force.

Bond surface See Bonding area.

Bond-to-bond distance The distance measured from the

bonding site on the die to the bond impression on the post,

substrate land, or ﬁngers, which must be bridged by a

bonding wire or ribbon.

Bond-to-chip distance In beam lead bonding the distance

from the heel of the bond to the component.

Bond tool The instrument used to position the lead(s)

over the desired bonding area and impart sufficient energy

to the lead(s) to form a bond.

Bondability Those surface characteristics and conditions

of cleanliness of a bonding area which must exist in order

to provide a capability for successfully bonding an inter-

connection material by one of several methods, such as

ultrasonic or thermo-compression wire bonding.

Bonding, die Attaching the semiconductor chip to the

substrate, either with an epoxy, eutectic or solder alloy.

Bonding area The area, deﬁned by the extent of a metal-

lization land or the top surface of the terminal, to which a

lead is or will be bonded.

Bonding island Same as Bonding land.

Bonding land A metallized area at the end of a thin

metallic strip to which a connection is to be made.

Bonding wire Fine gold or aluminum wire for making

electrical connections in hybrid circuits between various

bonding lands on the semiconductor device substrate and

device terminals or substrate lands.

BTAB The acronym for tape automated bonding when

the raised bump for each bond site is prepared on the tape

material as opposed to the bump being on the component.

Bugging height The distance between the hybrid sub-

strate and the lower surface of the beam lead device which

occurs because of deformation of beam leads during beam

lead bonding.

Chip The uncased and normally leadless form of an elec-

tronic component part, either passive or active, discrete or

integrated. chip-and-wire. A hybrid technology employing

face-up-bonded chip devices exclusively, interconnected to

the substrate conventionally (i.e. by ﬂying wires).

Chip carrier A special type of enclosure or package used

to house a semiconductor device or a hybrid microcircuit

which has metallized electrical terminations around its

perimeter rather than an extended lead frame or plug-in

pins.

Chopped bond Those bonds with excessive deformation

such that the strength of the bond is greatly reduced.

Co-ﬁring Processing the thick-ﬁlm conductors and resis-

tors through the ﬁring cycle at the same time.

Contact angle The angle made between the bonding

material and the bonding land.

Coplanar leads (ﬂat leads) Ribbon-type leads extending

from the sides of the circuit package, all lying in the same

plane.

Cratering Defect in which a portion of chip under the

ultrasonic bond is torn loose, leaving a pit, by excessive

amount of energy transmitted through the wire bond.

Die An uncased discrete or integrated device obtained

from a semiconductor wafer (see Chip).

Die bond Attachment of a die or chip to the hybrid sub-

strate.

Dielectric Materials that do not conduct electricity and

that are used for making capacitors, for insulating conduc-

tors (as in crossover and multilayer circuits), and for encap-

sulating circuits.

Digital circuits Applied normally for switching applica-

tions where the output of the circuit normally assumes one

or two states (binary operation); however, three state opera-

tion is possible.

Direct contact A contact made to the semiconductor die

when the wire is bonded directly over the part to be elec-

trically connected, as opposed to the expanded contact.

Doping The addition of an impurity to a semiconductor

to alter its conductivity.

Face bonding The opposite of back bonding. A face

bonded semiconductor chip is one that has its circuitry side

facing the substrate. Flip-chip and beam lead bonding are

the two common face bonding methods.

Field trimming Trimming of a resistor to set an output

voltage, current, etc.

December 1989 IPC-D-859

Film Single or multiple layers of coatings of thin or thick

material used to form various elements (resistors, capaci-

tors, inductors) or interconnections and crossovers (con-

ductors, insulators). Thick ﬁlms are deposited by screen

printing.

Film conductor A conductor formed in place on a sub-

strate by depositing a conductive material by screening,

plating, or evaporation techniques.

Film network An electrical network composed of a thin

and/or thick ﬁlm components and interconnections depos-

ited on a substrate.

Final seal The manufacturing operation that completes

the enclosure of the hybrid microcircuit so that further

internal processing cannot be performed without delidding

or disassembling the package.

Fire The term used to describe the act of heating a thick-

ﬁlm circuit so that the resistors, conductors, capacitors,

etc., will be transformed into their ﬁnal form.

Firing sensitivity Refers to the percentage change caused

in the ﬁred ﬁlm characteristics due to a change in peak ﬁr-

ing temperature. The ﬁring sensitivity is expressed in units

of %/°C.

Flip chip A leadless, monolithic structure, containing cir-

cuit elements, which is designed to electrically and

mechanically interconnect to the hybrid circuit by means of

an appropriate number of bumps located on its face which

are covered with a conductive bonding agent.

Flip-chip mounting A method of mounting ﬂip chips on

thick or thin ﬁlm circuits without the need for subsequent

wire bonding.

Functional trimming Trimming a circuit element (usu-

ally resistors) on an operating circuit to set a voltage or

current on the output. (See Active trim)

Glassivation A method of semiconductor passivation by

coating the element with a pyrolytic glass deposition.

Header The base of a hybrid circuit package that holds

the leads.

Hybrid circuit A microcircuit consisting of elements

which are a combination of the ﬁlm circuit type and the

semiconductor circuit type, or a combination of one or both

of these types and may include discrete add-on compo-

nents.

Hybrid group (electrically and structurally similar cir-

cuits). Hybrid microcircuits which are designed to perform

the same type(s) of basic circuit function(s), for the same

supply, bias, and single voltages and for input-output com-

patibility with each other under an established set of load-

ing rules, and which are enclosed in packages of the same

construction and outline.

Hybrid integrated circuit A microcircuit including thick

ﬁlm or thin ﬁlm paths and circuit elements on a supporting

substrate, to which active and passive micro-devices are

attached, either prepackaged or in uncased form as chips,

usually all enclosed in a suitable package (hermetic or

epoxy type). Used interchangeably with hybrid circuit and

hybrid integrated circuit.

Hybrid microcircuit A microcircuit that involves an insu-

lating substrate on which are deposited networks, consist-

ing generally of conductors, resistors, and capacitors, and

to which are attached discrete semiconductor devices

and/or monolithic integrated circuits and/or passive ele-

ments to form a packaged assembly. Used interchangeably

with hybrid circuit and hybrid integrated circuit.

Integrated circuit A microcircuit (monolithic) consisting

of interconnected elements inseparably associated and

formed in place on or within a single substrate (usually

silicon) to perform an electronic circuit function.

Junction (1) in solid state materials, a region of transi-

tion between p- and n- type semiconductor material as in a

transistor or diode. (2) A contact between two dissimilar

metals or materials (e.g., in a thermocouple or rectiﬁer). (3)

A connection between two or more conductors or two or

more sections of a transmission line.

Junction temperature The temperature of the region of

transition between the p- and n-type semiconductor mate-

rial in a transistor or diode element.

Land A portion of a conductive pattern usually used for

electrical connection, component attachment, or both.

Layer One of several ﬁlms in a multiple ﬁlm structure on

a substrate.

L cut A trim notch in a ﬁlm resistor that is created by the

cut starting perpendicular to the resistor length and turning

90° to complete the trim parallel to the resistor axis thereby

creating an L-shaped cut.

Lead frames The metallic portion of the device package

that completes the electrical connection path from the die

or dice and from ancillary hybrid circuit elements to the

outside world.

Loop The curve or arc by the wire between the attach-

ment points at each end of a wire bond.

Loop height A measure of the deviation of the wire loop

from the straight line between the attachment points of a

wire bond. Usually, it is the maximum perpendicular dis-

tance from this line to the wire loop.

Micro-bond A bond of a small wire, such as 0.025 mm

[0.001 inch] diameter gold, to a conductor or to a chip

device.

Microcircuit A small circuit (hybrid or monolithic) hav-

ing a relatively high equivalent circuit element density,

which is considered as a single part on (hybrid) or with

(monolithic) a single substrate to perform an electronic cir-

cuit function. (This excludes printed wiring boards, circuit

IPC-D-859 December 1989

card assemblies, and modules composed exclusively of dis-

crete electronic parts.)

Microcircuit module An assembly of microcircuits or an

assembly of microcircuits and discrete parts, designed to

perform one or more electronic circuit functions, and con-

structed such that for the purposes of speciﬁcation testing,

commerce, and maintenance, it is considered indivisible.

Micro-components Small discrete components such as

chip transistors and capacitors.

Microwave integrated circuit A miniature microwave

circuit usually using hybrid circuit technology to form the

conductors and attach the chip devices.

Monolithic ceramic capacitor A term sometimes used to

indicate a multilayer ceramic capacitor.

Monolithic integrated circuit An integrated circuit con-

sisting of elements formed in place on or within a semicon-

ductor substrate with at least one of the elements formed

within the substrate.

MOS device Abbreviation for a metal oxide semiconduc-

tor device.

Multichip integrated circuit An integrated circuit whose

elements are formed on or within two or more semiconduc-

tor chips which are separately attached to a substrate or

header.

Multichip microcircuit A microcircuit consisting solely

of active dice and passive chips which are separately

attached to the major substrate and interconnected to form

the circuit.

Nailhead bond See Ball bond.

Neck break A bond breaking immediately above gold

ball of a thermo-compression bond.

Off bond Bond that has some portion of the bond area

extending off the bonding land.

Overglaze A glass coating that is over another component

or element, normally for physical or electrical protection.

Package The container for an electronic component(s)

with terminals to provide electrical access to the inside of

the container. In addition, the container usually provides

hermetic and environmental protection for, and a particular

form factor to, the assembly of electronic components.

Package cap A cuplike cover that encloses the package

in the ﬁnal sealing operation.

Package lid A ﬂat cover plate that is used to seal a pack-

age cavity.

Packaging and Interconnecting (P/I) structure The gen-

eral term for a completely processed printed board, ceramic

substrate with interconnection wiring, or other combina-

tions of substrates and interconnection wiring, used for the

purpose of mounting components.

Purple plague One of several gold-aluminum compounds

formed when bonding gold to aluminum and activated by

re- exposure to moisture and high temperature. Purple

plague is purplish and very brittle, potentially leading to

time- based failure of the bonds. Its growth is highly

enhanced by silicon to form ternary compounds.

Push-off strength The amount of force required to dis-

lodge a chip device from its mounting land by application

of the force to one side of the device, parallel to the mount-

ing surface.

Resistor paste calibration The characterizing of a resistor

paste for Ω/square value, thermal coefficient of resistance,

and other speciﬁed parameters by screening and ﬁring a

test pattern using the paste and recording the results.

Sagging or wire sag The failure of bonding wire to form

the loop deﬁned by the path of the bonding tool between

bonds.

Search height The height of the bonding tool above the

bonding area at which ﬁnal adjustments in the location of

the bonding area under the tool are made prior to lowering

the tool for bonding.

Semiconductor carrier A permanent protective structure

which provides for mounting and for electrical continuity

in application of a semiconductor chip to a major substrate.

Semiconductors Solid materials such as silicon that have

a resistivity midway between that of a conductor and a

resistor. These materials are used as substrates for semicon-

ductor devices such as transistors, diodes, and integrated

circuits.

Serpentine cut A trim cut in a ﬁlm resistor that follows a

meandering repetitive pattern to effectively increase the

resistor length and increase resistance.

Smeared bond A bond impression that has been distorted

or enlarge by excess lateral movement of the bonding tool,

or by the movement of the device-holding ﬁxture.

Squash-out The deformed area of a lead which extends

beyond the dimensions of the lead prior to bonding.

Substrate (of a microcircuit or integrated circuit) The

supporting material upon which the elements of a hybrid

microcircuit are deposited or attached or within which the

elements of an integrated circuit are fabricated.

Tail (of the bond) The free end of wire extending beyond

the bond impression of a wire bond from the heel.

Tail pull The act of removing the excess wire left when a

wedge or ultrasonic bond is made.

Thick ﬁlm A ﬁlm deposited by screen printing processes

and ﬁred at high temperature to fuse into its ﬁnal form. The

basic processes of thick-ﬁlm technology are screen printing

and ﬁring.

December 1989 IPC-D-859