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Back end
A slang term frequently applied to the assembly and test portion of the semiconductor manufacturing process (see Front end)
Backside abrasion
A process whereby the backside of a finished wafer is cleaned using a fine-granular powder under air pressure in order to remove all oxidation or any other materials. The resulting level of wafer cleanliness allows better die attach of dice from the wafer
Back-end of line (BEOL)
Process steps from contract through completion of the wafer prior to electrical test. Also called back end
Backgrind
An operation using an abrasive on the back side of a substrate to achieve the necessary thinness for scribing, cutting, and packaging of die
Background
In the bar code marking of silicon wafers, the uniform, lighter or more reflective region that provides contrast for the darker bars of a bar code symbol, including, the "quiet zones."
Background counts
In particle counting, signal of particle counts that is observed during analysis of a particle-free standard test specimen. Background particle counts include electronic noise, particle contributed by the test apparatus, and signals induced by surface roughness.
Backside
back surface
Back surface
Of a semiconductor wafer, the exposed surface opposite to that on which active semiconductor devices have been or will be fabricated
Bake
In equipment exhaust systems, adjustments made after the ventilated equipment and the ventilation system are installed to ensure that air flow to each piece of ventilated equipment is within design specifications
Ball-gird array (BGA)
An integrated circuit surface mount package with an area array of solder balls that are attached to the bottom side of a substrate with routing layers. The die
Ball bonding
Normally employed with gold wire, ball-bonding employs a bonding head, which compresses the end of the wire under high heat to flatten it onto a large area of the bonding pad. The term is derived from the round appearance of the bond when viewed from above. Ball bonding is frequently employed with small geometry die (such as transistors), since a ball bond of 1 mil wire can be accomplished with a 2.5-mil bond width, whereas an ultrasonic bond will typically be 4 mils in length. When ball bonding is employed, the opposite end of the wire will often be stitch bonded, since it is difficult to ball bond at both terminals.
Baseline
A detailed definition of a device's electrical and mechanical configuration, assembly, processing and testing used as a base from which to track subsequent changes
Back-end of line(BEOL)
Process steps from contact through completion of the wafer prior to electrical test. Also called back end.
Back oxide
A layer of silicon dioxide formed on the back of a wafer during oxidation
Back plate
In a flat panel display, for a panel that consists of two plates of glass (or substrates) bonded together, the plate farthest from the viewer of the display
Balancing
In equipment exhaust systems, adjustments made after the ventilated equipment and the ventilation system are installed to ensure that air flow to each piece of ventilated equipment is within design specifications
Ball-grid array(BGA)
An integrated circuit surface mount package with an area array of solder balls that are attached to the bottom side of a substrate with routing layers. The die is attached to the substrate using die and wire binding or flip-chip interconnection. Also called land-grid array, pad-grid array, or pad-array carrier.
Ball valve
A shutoff valve of the packed type that incorporates a round, internal dynamic member, or "ball" and containing one or mire through holes that connect the ports of the valve to each other. Also see shutoff valve and packed valve
Bandwidth
The difference between the highest and lowest values in a range of two pattern characteristics, such as efficiency. frequency, or impedance. The bandwidth of significant frequencies (frequencies that conform to standards or that are required for reliable frequencies) within a spectrum is expressed in hertz.
Background
In the bar code marking of silicon wafers, the uniform, lighter or more reflective region that provides contrast for the darker bars of a bar code symbol, including, the "quiet zones."
Banking pins
In flat panel display, round elements in a positioning fixture that define a coordinate system origin. And against which a substrate is placed for processing of inspection
Bar
See die, crossbar, and bar end
Bar code
In the bar code marking of silicon wafers, an array of parallel rectangular bars and spaces that together represent data elements of characters in a particular symbology
Bar code character
In the bar code marking of silicon wafers, a single group of bars and spaces that represent an individual number, letter, punctuation mark, or other symbol
Bare die
Individual, unpackaged silicon integrated circuits
Bar end
1.In the bar code marking of silicon wafers, the darker of less reflective element of a bar code symbol.
2.Of a wafer carrier, see crossbar
Barrier layer
See depletion layer
Bar web
In plastic and metal wafer carriers, the mass of material for structural support that may of may not be present on the crossbar. Also see wafer carrier and crossbar
Bar width
In plastic and metal wafer carriers, the distance or thickness of the bar when measured perpendicular to the top face. Also see wafer carrier and crossbar.
Base end to first slot
In quartz and high temperature wafer carriers, the distance from either end of the vase of a wafer carrier to the first slot
Base length
In plastic and metal wafer carriers, the horizontal distance from the vertical wafer center line to either side of the base. Also see wafer carrier and base.
Baseline
A specification or product that gas been formally reviewed and agreed on, which thereafter serves as a basis for further development and can be changed only through formal change control procedures
Base side to wafer center line
In plastic and metal wafer carriers, the horizontal distance from the vertical wafer center line to either side of the vase. Also see wafer carrier and base.
Base step height
In quartz and high-temperature wafer carriers, the distance from the bottom plane to the widest point of the base. Also see wafer carrier and base.
Base width
In quartz and high-temperature wafer carriers, the outside dimension of the base from side to side.
Basic cell
An arrangement of features or groups, as defined by SEMI P19-92, based on a specific nominal feature dimension
Batch
One or more sets of data or programs accumulated for processing in one no interactive job. A group of wafers intended for a process sequence, as opposed to single-wafer processing
Bay
Of a cleanroom, a confined area that contains equipment used for one or more steps in a process.
Bead
An individual spherical particle of an ion-exchange resin material
Behavior
In object-oriented technology, how an object acts and reacts.
Behavioral
A level of logic design that involves describing a system at a level of abstraction that does not involve detailed circuit elements, but instead expresses the circuits functionality linguistically or as equations.
Bell jar
A glass, quartz, or stainless steel chamber used to isolate substrate in a sub atmospheric environment for deposition or etch
Benchmarks
Standard circuits or tests that can be used to compare the performance of software programs or tools. Each program or tool is applied to the benchmark circuit and the results compared.
Bend radius
Of a fluorocarbon tube, the distance from the center of an imaginary circle on which the arc of the bent tube falls to a point on that arc.
BEOL
See back-end of line
Best focus
In the testing of photolithographic instruments, the position of a processed image surface in which the est. compromise of focus across the whole of the processed image is obtained, as defined by the application requirements for the processed image.
Beta test
Performance testing done on a pilot production version of a process tool installed at customer sites. The testing is performed by customers and monitored by the manufacturer's applications engineering group. No design changes are made during the testing period.
Bevel angle
The smaller of the angles between the wafer surface and the section plane.
BiCMOS design
The combination of bipolar and complementary metal oxide semiconductor design and processing principles on a single wafer or substrate
Bidrectional
In the bar code marking of silicon wafers, refers to a bar code that can be read successfully in either scanning direction, right to left of left to right.
Bin
Of particle measurement instruments, a subset of the total range of particles counted, based on size. Many particle counting instruments measure the size of a particle while counting and then sort the total number of counts into bins. Some instruments have the size ranges of the bins set at the factory, while some designs allow the user to set the ranges of the bins.
Binary
Numbering system using two as a base and requiring only two symbols, 0 and 1.
Binary intensity mask(BIM)
A mask consisting of patterned areas that transmit or do not transmit, for example, the common chrome-on-quartz mask.
Binary value
In the dot matrix code marking of silicon wafers, a dot in the wafer surface indicates the binary value 1. The absence of a dot, or a smooth surface surrounding a cell center point, indicates the binary value 0.
Binding energy
The value obtained by subtracting the instrumentally measured kinetic energy of an electron from the energy of the incident photon, corrected for an instrument work function
Biodegradable
Pertains to an organic material capable of decomposition as a result of attack by microorganisms.
Biofilm
a collection of microorganisms, extracellular polymeric products, and organic matter located at the interface in solid-liquid, gas-liquid, or liquid-liquid biphasic systems.
Bipolar
a collection of microorganisms, extracellular polymeric products, and organic matter located at the interface in solid-liquid, gas-liquid, or liquid-liquid biphasic systems
Bipolar transmission
See polar transmission
Bird's beak
A structural feature produced as a result of the lifting of the edges of the nitride layer during subsequent oxidation
Birefringence
A double-refraction phenomenon in which an unpolarized beam of light is divided into two beams with different directions and relative velocities.
Bit
(Memory Bit) Short for "Binary Digit." The smallest piece of data (a "1" or "0") that a computer recognizes. Combinations of 1s and 0s are used to represent one numeric or alphabetic character.
Blister ceramic
An enclosed, localized separation within or between the layers of a ceramic package that does not expose an underlying layer of ceramic or metallization
Blister metal
In packaging, an enclosed, localized separation of a metallization layer from its base material (such as ceramic or another metal layer) that does not expose the underlying layer.
Block
In message transfer, a physical division of a message(a complete unit of communication).NOTE-In SECS-I, each block has a block header (a 10-byte data element used by the message and transaction protocols) and up to 244 bytes of data. For compatibility with SECS-I,SECS-II also recognizes the same block length for data;however,in SECS-II there is only a message header, not a header for each block.
Block length
In message transfer, the number of bytes sent in the block transfer protocol.
Block-level
Describes a high-level architectural schematic of a system or function that hides detail and displays a collection of circuit elements as a single block.
Block-number
A 15-bit field in the header for the numbering of blocks in a message.
Block transfer protocol
In message transfer, the SECS-I procedure used by a serial line to establish the direction of communication and to provide the environment for passing message blocks. NOTE-A block consists of a 10-byte header plus up to 244 bytes of data.
Boat map
A drawing that shows the relative location of product, test, and dummy wafers in a diffusion cycle.
Boiling point(bp)
The temperature of a liquid at which the vapor pressure equals the prevailing atmospheric pressure. The normal boiling point is specified at one atmosphere.
Bond ability
Surface conditions of a bonding area that provide a capability for successfully bonding an interconnection material.
Bonded process
A manufacturing-oriented technique to build silicon on insulator substrate. The process involves bonding two oxidized wafers together then thinning the top or active layer to the desired thickness
Bond finger
1. In ceramic packages, an area of refractory metal that has been plated, usually with gold, and is intended for wire bonding. Also see lead flat surface.
2. The area of lead frames designated for the attachment of bonding wires between the bond pads on the die and the lead frame
Bonding area
In packaging, the area of a lead frame designated for the attachment of small diameter bonding wires from the bonding pads on the die to the lead frame. These areas are often coined if the lead frames are stamped to provide a flat surface for bonding. The designated area does not necessarily correspond to the physical dimensions of the bond finger
Bonding pads
Relatively large metal areas on a die used for electrical contact with a package or probe pins.
Bond-off
An extra bond attached to the edge of the post or land area of a package (but never to the bonding pad on the die) for the purpose if clearing the bonding machine.
Bond pull
Pulling of the bond wires to destruction to determine the strength of the bonds (See MIL-STD-883, Method 2011.) See also Nondestructive bond pull
Booties
Conductive shoe covers worn to reduce contamination in a cleanroom
Border column
In the dot matrix code marking of silicon wafer, the outermost column of a dot matrix.
Border row
In the dot matrix code marking of silicon wafers, the outermost row of a dot matrix
Boron (B)
a nonmetal that is also a p-type dopant for silicon. The most common source of boron is the gas diborane (B2H6).
Boron implant
The operation whereby boron atoms are accelerated and injected into the surface of a wafer or substrate. The species are physically implanted into the bulk of the silicon to create a locally conductive p-type area
Boron trichloride (BCl3)
A colorless gas at room temperature and atmospheric pressure. Boron trichloride fumes in the presence of moist air and has a choking odor. This gas is used as a gas etchant of metals such as aluminum. It also is used in boron doping
Boron trifluoride (BF3)
A colorless gas that fumes in moist air and has a pungent odor. This gas is nonflammable and does not support combustion. It is toxic when inhaled and is corrosive to the skin. Boron trifluoride is used in ion implantation and doping. Also see ion implantation.
Bottom formed width
In packaging, the widest spread of the leads, measured to the outside of the lead or foot, after lead forming. Also see lead frame and package.
Bottom plane
In a wafer carrier, a horizontal plane tangent to the base. Also see wafer carrier and base
Bottom protrusions
See top or bottom protrusions
Boundary scan
A scan path that allows the input/output pads of an integrated circuit to be both controlled and observed.
Bow
Of a semiconductor wafer, the deviation of the center point of the median surface of a free, unclamped wafer from a median surface reference plane established by three points equally spaced on a circle with diameter a specified amount less than the nominal diameter of the wafer.
Box
An environmentally controlled enclosure for a cassette containing wafers of disks. A box includes a box door and box latches. Also called container
Box door
A removal bottom for the box that contains a means for properly positioning the wafer cassette. Also see Box.
Box latches
For wafers less than or equal to 150 mm, mechanical latches that hold the box door in position until activated by the latch pins. Upon activation, a portion of each box latch engages a latch cavity and smaller, thereby locking the box to the port plate
Bridge
1: a defect in which two adjacent areas connect because of misprocessing such as poor lithography, particle contamination, underdevelop, or etch problems. [SEMATECH] Also called short.
2: software that allows access to, and combination of, data from incompatible databases.
Bridged interface
A general term for the interconnection between legacy systems. See legacy system.
Bridging fault
A fault modeled as a short-circuit between two nets on a die.
Brightfield illumination
The illumination of an object so that it appears on a bright background
Brinell hardness test (BHT)
An indentation hardness test using calibrated machines to force a hard ball, under specified conditions, into the surface of the material under test and to measure the diameter of the impression after removal of the load
Bronchitis
An acute or chronic inflammation of the mucous membrane of the tracheobronchial tree.
Browse
To view the components of a structure through a user interface that allows easy navigation through the links connecting objects in the structure
Browser
A basic tool for the manipulation of a repository, displaying its objects, links and attributes. The browser also acts as a repository editor, allowing the creation and deletion of objects, modification of links and attributes, etc.
BTAB
See bumped tape automated bonding
Bubble
A spherical defect formed by air or other gas included in a substrate or film
Bubble ceramic
See blister ceramic
Bubble fluid
A liquid, containing soap or other bubble-generating medium, designed to detect leaks from inside a piping system to atmosphere.
Bubble metal/metallization
See blister metal
Buffer
1. A program routine or storage device that compensates for unequal data flow rates or event timing differences during the transfer of data between devices.
2. A substance added to a solution to attain higher consistency of solution strength over time.
Buffered hydrofluoric acid
An extremely hazardous corrosive used to each silicon dioxide from a wafer. This acid has a 20 to 30 minute reaction delay after contact with skin or eyes
Built-in self test (BIST)
Any of the methods of testing an integrated circuit that uses special circuits designed into the IC.This circuitry then performs test functions on the IC and signals whether the parts of the IC covered by the BIST circuits are working properly
Bulk CMOS
Conventional CMOS integrated circuit processes, so called because they are diffused into bulk silicon rather than on a substrate such as sapphire
Bulk gases
Common gases, such as nitrogen, hydrogen, oxygen, and argon that are used in such large quantities in wafer fabrication that they are pumped or piped into the facility
Bulk processes
Semiconductor processes affecting the bulk silicon, for example, silicon materials, implant, cleans and thermal processes.
Bumped tape automated bonding (BTAB)
The preparation of a raised bump site, usually gold or tin, at each bond site on tape bonding material
Bunny suit
A total-body garment worn by personnel in a cleanroom to reduce release of particles and contaminants into the air
Buried contact
A conductive region between two less conductive regions
Buried layer
1. a conductive layer between two less conductive films; for example, a localized n+ region in a p-type wafer that reduces the npn collector series resistance for integrated circuit transistors fabricated in an n-type epitaxial layer deposited on the p-type wafer.
2. in epitaxial silicon wafers, a diffused region in a substrate that is, or is intended to be, covered with an epitaxial layer.
Burn-in
The process of exercising an integrated circuit at elevated voltage and temperature.This process accelerates failure normally seen as "infant mortality"in a chip.The resultant tested product is of high quality.
Byte
A number of binary bits, usually eight, that represent one numeric or alphabetic character.
Junction burnout
See Thermal secondary breakdown.
Resistivity (ohm-cm)
The ratio of the potential gradient (electric field) parallel with the current to the current density/the amount of resistance to electrical current. In silicon, the resistivity is controlled by adding dopant impurities : lower resistivity is achieved by adding more dopant.
Calorie(cal)
A standard unit of heat equal to the amount of heat required to raise one gram of water one degree Celsius.
Capacitance
The property of a circuit element that permits it to store an electrical charge.
Polar transmission
a method of transmitting teletypewriter signals when current flows in opposite directions. Direct current flowing in one direction identifies the marking signal, and an equal current flowing in the opposite direction identifies the spacing signal.