B
In semiconductor manufacturing, the package assembly and test stages of production.
Includes burn-in and environmental test functions. Compare front
end.
The width measure of a signal or signal-carrying channel from the lowest to the highest
frequency (or bit rate). For analog signals, the width is in the frequency domain,
expressed in Hz. For digital signals, the width is in the time domain, expressed in bits
per second. In semiconductor devices, the bandwidth is the range of frequency (or bit
rate) in which the performance characteristics are within specified limits.
One of the three regions that form a bipolar transistor. It physically separates the
emitter and collector regions. Minority carriers are injected from the emitter into the
base, where they subsequently either recombine or diffuse into the collector. See also bipolar transistor, collector
and emitter.
The ability to simulate the behavior of a function described by a high-level
descriptive language such as C, Pascal, Verilog HDL and VHDL.
Bipolar Complementary Metal Oxide Semiconductor. An
IC technology combining the linearity and speed advantages of bipolar and the low-power
advantages of CMOS on a single IC. BiCMOS can operate at either ECL
(emitter-coupled-logic) or TTL (transistor-transistor-logic) levels, and is ideal for
mixed-signal devices. It has been predicted that BiCMOS will eclipse CMOS in the '90s,
just as CMOS edged out MOS and bipolar circuits in the '80s. Intersil is developing a
broad family of BiCMOS processes that combine analog, digital and power functions on a
single chip. See also CMOS, ECL
circuit, TTL, HBC-10 and Power BiMOS.
Bipolar Metal Oxide Semiconductor. A general term to refer
to bipolar and MOS on one chip. Sometimes used interchangeably with "BiCMOS."
See also Power BiMOS.
A number system employed in computers and digital systems, in which successive digits
are coefficients of powers of the base 2, rather than the base 10. For example, the
decimal number 13 is represented by the binary number 1101 (1 x 23 + 1 x 22
+ 0 x 21 + 1 x 20). Since the only values in the binary system are
"0" and "1," quantities, or BITS (binary digits) are represented
electronically with either of two conditions, typically a high voltage representing a
"1" and a low voltage representing a "0". See bit.
An active semiconductor device formed by two P-N junctions whose function is
amplification of an electric current. Bipolar transistors are of two types: NPN and PNP,
depending on the manner in which the two P-N junctions are combined. Bipolar transistors
have three sections: emitter, base, and collector. Operation of a bipolar transistor
depends on the migration of both electrons and holes, in contrast to field-effect
transistors, where only one polarity carrier predominates.
Building In Reliability.
Binary digit. A digit (1 or 0) in the representation of a number in
binary notation. The smallest unit of information recognized by a digital computer. Used
to represent two states in the binary number system. Eight bits make a byte. See binary number system.
Bill of Materials. List of specifications that uniquely defines
manufacturing sequence, materials and procedures utilized in the manufacture of a specific
product.
A composite dielectrically isolated substrate formed by fusing together (at high
temperature) the oxidized surfaces of two individual silicon substrates. Bonded wafers are
being developed to extend the Intersil DI (dielectric isolation) technology to wafers as
large as six inches in diameter. ICs formed in such wafers provide higher breakdown
voltage and a higher level of radiation resistance than devices fabricated in conventional
DI substrates.
The process of connecting wires from the package leads to the chip (or die) bonding
pads. Part of the assembly process. Alternately, the process of securing a semiconductor
die to a lead frame or package. See bond pad.
An area (typically 100µm x 100µm) on the periphery of a silicon die for making
connection to one of the package pins. A small-diameter gold or aluminum wire is bonded to
the pad area by a combination of heat and ultrasonic energy. See bonding.
The addition of a partitioning test circuit to the input/output boundary of an IC to
control and monitor the logic state of its internal circuit nodes.
BoroPhosphoSilicate Glass.
BPSG is an oxide primarily used as a field dielectric. It is deposited in a PECVD
reactor using a mixture of SiH4, B2H6, and PH3
with N2O in a temperature and pressure controlled environment. BPSG is used
principally because of its' lower melting point (viscous flow temperature) compared to
other oxides. BPSG can be deposited over delineated polysilicon and can 'flow' at
temperatures low enough to not significantly alter the dopant profiles in the underlying
device silicon. This smoothing improves metal-level step coverage. BPSG is not a good
passivation material because it is hydroscopic in nature. See PECVD
- In electronics: a device that is used to provide compatibility between two signals.
Typically the device is used to change the voltage or current level capability,
e.g. interfacing the output of a CMOS device to the input of a TTL device. See also bus driver, CMOS, TTL.
- In computing: an area of memory used for temporary storage of information.
Typically, the buffer is used to pass or share information between different processes.
- In chemistry: a solution characterized by the ability to withstand changes in pH when
limited amounts an acid or base are added.
Four or more parallel conductors in an information processing system along which
information is transmitted from one part to another. The microprocessor, peripherals,
memory and other components are interconnected by a common bus.
An integrated circuit added to the bus to facilitate sufficient drive to the CPU when
several peripheral devices are tied to the bus. Drivers are necessary because of
capacitive loading, which slows down the data rate and prevents proper time sequencing of
system operation. See buffer.
From the expression "by eights." A group of eight contiguous bits (binary
digits) handled as a unit in computer processing. A byte can store one alphanumeric
character. A kilobyte (KB) is 1024 bytes or 8192 bits. A megabyte (MB) is 1024 kilobytes
or 1,048,576 bytes or 8,388,608 bits.
