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Microelectronics

Analog circuit: An electronic circuit in which voltages and currents vary with the intensity of an external quantity (e.g., sound level).
ASIC: Application Specific Integrated Circuit; an integrated circuit which is custom designed to perform a particular function within a system.

ATE: Automatic Test Equipment; computer controlled equipment used in the production testing of packaged ICs. Test voltage sequences (test pattern) are applied and responses compared to data on file or to a known-to-be-good IC.
Back-end design: Design activities starting with either a netlist or hardware description language version of a chip design and ending with the layout (physical design) of the chip.
BiCMOS: An integrated circuit technology in which both CMOS and bipolar junction transistors (BJTs) can be produced on the same chip.
BIST: Built-in Self Test; the ability of an IC to internally generate the sequence of test voltages required to verify its functionality.
BJT: Bipolar Junction Transistor; a transistor in which current is controlled by the voltage impressed across a crystal interface between p and n type semiconductor.
CAD: Computer Aided Design; the use of computer programs to help create integrated circuits and systems.
Cell Library: A set of computer data files which contain all the information needed to model, simulate, and layout pre-designed integrated circuit modules which can then be automatically interconnected.
Characterization: The process of collecting measured electrical data about the operation of an integrated circuit component or module to enable it to be accurately modelled in a computer simulation.
Chip: A single die cut from a wafer which usually contains a single integrated circuit.
CMOS: Complementary Metal-Oxide-Semiconductor; a process technology which is capable of producing MOS transistors with both n and p type semiconductor conducting channels. Most CMOS circuits contain equal numbers of n and p type transistors.
Cores: A complex, pre-designed functional module (e. g. a digital signal processor) that is integrated within a larger chip.
DC: Direct Current; the external, constant-voltage, single polarity electrical power supplied to an integrated circuit.
Defect: An imperfection in the surface structure of a silicon wafer which causes one or more chips to malfunction.
Design kit: A collection of technical information, software, and computer data files which enable the designer to model, simulate, and layout integrated circuits using a specific technology (e. g. 0.8 micron CMOS).
DFT: Design for Testability; the practice of adding special circuits as part of an IC to aid in the testing of the fabricated chips.
Die: A single integrated circuit within a wafer; chip
Digital circuit: An electronic circuit in which the intensity of an external quantity (e.g., sound level) is represented by a series of fixed voltages using a numerical code (e.g., the binary code requires only two voltage levels).
DRAM: Dynamic Random Access Memory; memory circuits which require regular refreshing of the data stored in each memory cell. The circuits are more compact than static RAM but do not retain data when the refresh signal (clock) or power is turned off.
DRC: Design Rules Check; operation carried out by a CAD tool which compares the dimensions, separations, overlaps, etc. of a chip layout to the minimum and maximum dimensions specified by the design rules for a particular process.
DSM: Deep Sub-Micron; fabrication processes that are defined using dimensions less than 0.5-micron or 0.35-micron are often described as DSM. Any activities aimed at using these processes are deemed DSM, for example, a DSM digital design flow.
DSP: Digital Signal Processing; the manipulation of information which has been numerically coded using a digital circuit. Analog data (signals) are first converted to digital form by an analog-to-digital (A/D) converter, then processed using digital circuits, then converted back to analog form by a digital to analog (D/A) converter.
E-beam: Electron Beam; a focussed beam of high energy electrons used to expose photo-sensitive film in the production of integrated circuit masks (photo-masks), or the circuit elements themselves.
EDA: Electronic Design Automation; the name used for activities or facilities that involve software design aids used in chip design, or the industry sector making the aids.
EPROM: Erasable Programmable Read Only Memory; read only memory (see below) which can be preprogrammed by the user and subsequently erased and preprogrammed with new data as the need arises.
Etch: A chemical process used to selectively remove parts of an integrated circuit during fabrication.
Fabrication: The production of an integrated circuit through a series of processing steps carried out on a semiconductor wafer.
FPGA: Field Programmable Gate Array; an integrated circuit fabrication technology in which pre-fabricated circuit modules are electrically configured by the user to meet specific design requirements on a chip-by-chip basis.
GaAs: Gallium Arsenide; a semiconductor crystal which is a compound of the elements gallium and arsenic. Its electronic properties offer the potential for higher speed electron conduction than in silicon, but at the expense of greater power consumption.
array: An integrated circuit fabrication technology in which the final metal interconnect layers of an otherwise pre-fabricated wafer are patterned in accordance with user-supplied design data.
Hardware: The actual integrated circuit chips and interconnections in a system as opposed to the computer programs and data (software) which may be stored in memory (which is itself hardware).
HDL: Hardware Description Language; A human and computer-readable language used to describe the functions and/or behavior of an integrated circuit or system which can be used to carry out computer simulation or automatically synthesize the actual circuits necessary to implement the specified functions.
IC: Integrated Circuit; the interconnection of multiple electronic circuit components fabricated on a single semiconductor crystal. Often used interchangeably with chip.
Interconnect: The metal and silicon patterns on an integrated circuit which serve to electrically interconnect components (e. g. transistors) and to supply power and distribute electrical data throughout the circuit.
Layout: The physical location of the components and interconnections which make up an integrated circuit. The layout data include the geometrical patterns on each of the masks required during processing.
Logic gate: A circuit module which performs a common logical function such as inversion or logical AND and OR operations.
Mask: The photographic film used to isolate portions of a wafer during a processing step. This photo-mask may be used to control the patterning of a layer of photoresist or other material on the surface of the wafer which acts as the actual process mask.
MCM: Multi-Chip Module; an integrated circuit package which contains two or more interconnected chips.
MEMS: Microelectromechanical Systems; integrated circuits which contain both electronic circuits and microscopic machines such as force transducers, valves, and motors.
Methodology: The structured, hierarchical series of steps used in the design of a circuit or system.
Modelling: The capture of the electrical and functional behavior of a circuit within a computer program which is then used to test the response of the circuit to various input data without actually fabricating the chip.
Module: An interconnected subsystem of integrated circuit components, usually designed to act as a building block for more complex circuits.
MOS: Metal-Oxide-Semiconductor; the fabrication technology which is used to produce silicon field effect transistors in which the flow of current is controlled by the strength of the electric field between the gate and the conducting channel, which are separated by an insulating layer of silicon dioxide.
MST: Microsystems Technology; similar to MEMS with or without the electronic circuitry (e. g. optical, mechanical or fluidic structures).
Netlist: A computer file listing all of the components together with the details of how they are interconnected to form the overall circuit.
Optoelectronics: Integrated circuits and systems which combine optical elements (e. g. lasers and photo detectors) with microelectronic circuits, often as part of a single chip.
Package: The plastic or ceramic structure that encloses a chip and facilitates connections to the chip through a set of pins which are usually soldered to a printed circuit board. The package may be first inserted into a socket to permit easy removal.
PCB: Printed Circuit Board; an insulating card with one or more layers of copper interconnections onto which are soldered integrated circuit packages and other electronic components. PCBs are usually plugged into sockets that may be interconnected through a wire bus.
Photo-mask: The photographic film (glass plate) which contains the masking pattern required for a particular wafer processing step.
Photoresist: Light-sensitive material that is used to form selectively protective masking layers during wafer processing. A photo-mask is used to define the areas of photoresist exposed to light, which are subsequently removed by a solvent, leaving the required pattern on the wafer surface. The entire process is called photolithography.
RAM: Random Access Memory; memory arrays which permit reading or writing data in any memory cell selected using a cell address code.
Reverse engineering: The process of determining the actual circuit by study of the geometrical layout of a fabricated chip.
ROM: Read Only Memory; an electronic or disk-based data storage medium in which preprogrammed data can be accessed as required by a system.
RF: Radio Frequency; electrical voltages which oscillate at frequencies and in a manner which make possible their electromagnetic transmission through space.
Semiconductor: A class of materials (e. g. silicon, gallium arsenide) that exhibit electrical properties mid-way between insulators (e.g., plastic) and conductors (e. g., copper).
Silicon: A pure crystalline element (Si) which is the most commonly used semiconductor material for the fabrication of integrated circuits.
Simulation: The use of a CAD tool which mimics the behavior of the actual circuit through a collection of sub-circuit models and so enables designers to test and debug circuits before layout and fabrication.
Software: Computer programs and data which are used in conjunction with hardware to implement a complete microelectronic system (e.g., a personal computer or a telecommunications network).
SRAM: Static Random Access Memory; memory circuits which permit the storage and retrieval of data from any desired memory cell. The data remain stored as long as power is applied.
Standard cell: A pre-designed integrated circuit module that implements a specific function. The data required to use the cell as part of a more complex circuit are contained in a computer file that can be accessed by other CAD tools. Standard cells are designed to be interconnected by simple abutment with other cells from the same cell library.
Synthesis: The CAD operation of automatically generating an integrated circuit layout from a high-level description (e. g. using a hardware description language) of the desired circuit function and behavior.
VHDL: Very high-speed integrated circuit Hardware Description Language; a standardized example of a hardware description language that has the capability of specifying function and behavior of circuits.
VLSI: Very Large Scale Integration; a somewhat generic term applied to most modern integrated circuits which comprise from hundreds of thousands up to millions of individual components. Also applied to systems that employ VLSI circuits.
VXI: VME bus extensions for instrumentation. An industry standard in test instrumentation.
Wafer: The thin ( a few hundred microns) slice sawn from a cylindrical semiconductor crystal which serves as the substrate for the fabrication of multiple individual integrated circuits or chips.
Workstation: A somewhat generic term applied to any computer that has the performance and networking capability required to run the CAD tools used in engineering design.
Yield: The percentage of good chips compared to the total chips produced per wafer. Yield generally increases as a particular process becomes tuned to the production of a particular chip but is limited by physical defects in the semiconductor crystal surface.

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