SEMATECH Dictionary of Semiconductor Terms

A-Am | An-Az | B | C-Ch | Ci-Com | Con-Cz | D-De | Df-Dz | E-En | Eo-Ez | F-Fl
Fm-Fz | G | H | I | J-K | L | M-Mes | Met-Mz | N | O | P-Ph | Pi-Pq | Pr-Pz | Q | R
S-Se | Sh-So | Sp-Sta | Ste-Sz | T-Th | Ti-Tz | U-V | W-Z

"D - De "

daisy chained adj		in a cluster tool, connected so that the removal of one component causes the interruption of the circuit to another component. [SEMI E20-91]
damascene n		an integrated circuit process by which a metal conductor pattern is embedded in a dielectric film on the silicon substrate. The result is a planar interconnection layer. The creation of a damascene structure most often involves chemical mechanical polishing of a nonplanar surface resulting from multiple process steps. A damascene trench is a filled trench. [1994 National Technology Roadmap for Semiconductors]
damage n		1 : of a single-crystal silicon specimen, a defect of the crystal lattice in the form of irreversible deformation that results from mechanical surface treatments such as sawing, lapping, grinding, sandblasting, and shot peening at room temperature without subsequent heat treatments. [ASTM F1241]2 : any yield or reliability detractors other than those related to design, process specification violations, or particles. [SEMATECH]
damage depth (Tz) n		the maximum thickness of the damage region as revealed by preferential etch that removes silicon in the region of the deformation. [ASTM F1241]
dambar n		on leadframes, a feature for plastic molded packages that blocks (dams) the flow of the plastic compound to the external lead areas of the leadframe during the molding cycle. Dambars electrically short the leads together and must be removed (trimmed) before electrical testing of the device can be performed. [SEMATECH]
data n, pl also sing as collective noun; as sing entity, datum)		(1 : information, including programs, program instructions, and the information used or produced by a computer. [SEMATECH] 2 : any representation to which meaning is or might be assigned (for example, characters). [SEMI E13-91]
data conversion n		the changing of data from one format to a different but equivalent format to allow its use in a different computer-aided design application. [1994 National Technology Roadmap for Semiconductors]
data dictionary n		1 : a collection of names of all data items used in a software system, together with relevant properties of those items; for example, length of data item, representation, etc. [SEMATECH] 2 : a resource that assists management, database administrators, systems analysts, and application programmers in planning, controlling, and evaluating the collection, storage, and use of data. [SEMATECH] 3 : a set of definitions of data flows, data elements, files, databases, and processes referred to in a leveled data flow diagram set. Also see repository. [SEMATECH]
data-driven adj		pertaining to a mode of executing a program in a data flow system in which an instruction is executed when all its input values are present. [SEMATECH] Contrast menu-driven.
data integration n		1 :the degree to which tools can share data through a framework. The degree of integration is dependent on the granularity of data that a framework supports. [SEMATECH] 2 : The means by which design data is transferred between computer-aided design applications. [1994 National Technology Roadmap for Semiconductors]
data management n		the organization and control of design data (files or records) to assure proper security, integrity, and availability of the data. [1994 National Technology Roadmap for Semiconductors]
data model n		one of several standard models used to describe data organization. Data models usually describe data as either rigid hierarchies or networks. The relational data model, based on viewing data as tables, is an example. [SEMATECH]
datum plane (M) n		of a leadframe, the line that forms the top formed width. [SEMI G2-87]
datum point n		in wafer transport systems, the left rear corner of wafer transport equipment; formed by the intersection of the planes that define the left side, back side, and wafer plane. [SEMI E8-92]
D/B		see die bonding.
dBa		see adjusted decibel.
DC test		A sequence of direct current (DC) measurements performed on integrated circuit pads to determine probe contact, leakage currents, voltage levels on input and output, power supply currents, etc. [1994 National Technology Roadmap for Semiconductors]
dead time n		in mass flow controller testing, the interval of time between the set point step change and the start of the resulting observable response. [SEMI E17-91]
dedicated purge gas cylinder n		a cylinder of gas dedicated to the task of purging undesirable gas from piping manifolds. [SEMI Chemicals/Gases, Vol. 1, 1990 (no longer in print)]
deep level impurity n		a chemical element that, when introduced into a semiconductor, has an energy level (or levels) that lies on the midrange of the forbidden energy gap, between the energy levels of the dopant impurity species. [ASTM F1241]
deep ultraviolet (DUV) masks n		the master pattern or reticle used in DUV projection lithography (generally, wavelengths between 248 nm and 193 nm). The mask contains the pattern that is to be printed on the wafer, usually magnified at 4X. [SEMATECH]
defect n		for silicon crystals, a chemical or structural irregularity that degrades the ideal silicon crystal structure or the thin films built over the silicon wafer. 2 : a pit, tear, groove, inclusion, grain boundary, or other surface feature that is either characteristic of the material or a result of its processing and that is not a result of the sample preparation. [SEMATECH] Also called anomaly.
defect density n		the number of imperfections per unit area, where imperfections are specified by type and dimension. [ASTM F127-84] Also see defect.
defect level n		the number of die in parts-per-million that are shipped to customers and that are defective even though the test program declares them to be good. [1994 National Technology Roadmap for Semiconductors]
defect, photomask n		any flaw or imperfection in the opaque coating or functional pattern that will reproduce itself in a resist film to such a degree that it is pernicious to the proper functioning of the microelectronic device being fabricated. [SEMI P2-86]
deflashing n		the process used to remove excess molding compound, flash, or resin bleed from the body of a molded plastic package and the leads. The excess compound might be present as a normal characteristic of the mold leadframe/interface or due to imperfections in the mold, such as wear. Flash may be removed by mechanical punches or medial deflashing. [SEMATECH]
defocus n		in the measurement of photolithographic instruments, the distance, perpendicular to the image plane, between the processed image plane and the plane of best focus. [SEMI P25-94]
degating n		the process of removing the gate from a plastic molded device. This operation may be performed during mechanical deflashing with a trimming punch or by using media deflashing. [SEMATECH] Also see gate feature.
degree of hazard n		the inherent ability of a chemical to do harm due to its toxicity, corrosiveness, flammability, or other characteristic, and the potential for that chemical to contact persons or the environment. [SEMI S2-93]
dehydration bake n		wafer bake (typically 150-2505C) in a nitrogen atmosphere to remove absorbed moisture prior to application of resist. [SEMATECH]
deionization (DI) n		an ion-exchange process in which all charged species or ionizable organic and inorganic salts are removed from a solution. [SEMATECH]
delamination n		in a cofired ceramic package, chip carrier, dual inline package, pin grid array, etc., the separation of one ceramic layer from another. [SEMI G61-94] Also see package.
delay fault n		a fault that has the effect of causing a signal to appear late in arriving at a destination. [1994 National Technology Roadmap for Semiconductors]
deliquescent adj		the property of a substance that inclines the substance to absorb moisture from the atmosphere until it dissolves. An example of substances having this property would be water-soluble salts. [SEMATECH] Also see hydrophilic.
density n		1 : a measurement of how closely the circuits on a die are spaced. [SEMATECH] 2 : weight per unit volume (w/v), expressed as grams per liter for gases at 05C, one atmosphere. Density is expressed as grams per milliliter for liquids and solids. [SEMI C3-90]
density transition n		the difference in photographic density between points of maximum and minimum density in the transition region between an exposed area and an unexposed area. [ASTM F127-84] Also see photomask.
depletion implant n		a process wherein silicon is bombarded by ions to establish a normally "on" transistor in the silicon directly under the gate electrode. A normally "on" transistor requires no voltage applied to the gate electrode for current to flow. [SEMATECH]
depletion layer n		in a semiconductor, a region in which the charge-carrier charge density is not sufficient to neutralize the net fixed-charge density of donors and acceptors. [SEMI M1-94 and ASTM F1241] Also called barrier layer, blocking layer, and space-charge layer.
depletion width n		in a semiconductor, the width of the region near a metal-semiconductor contact in which the charge-carrier density is insufficient to neutralize the fixed-charge density of donors and acceptors. [ASTM F1241]
deposition (dep) n		an operation in which a film is placed on a wafer without a chemical reaction with the underlying layer. [SEMATECH]
depth of focus (DOF) n		a plus or minus deviation from a defined reference plane wherein the required resolution for photolithography is still achievable. [SEMATECH] Also called depth of field.
depth of focus map n		in the measurement of photolithographic instruments, a plot, for each position in the image field, of the greatest defocus in the positive direction and the greatest defocus in the negative direction in which the processed image is sufficiently resolved for practical use. [SEMI P25-94]
descum n		a plasma operation after develop that ensures full removal of resist from uncovered areas. [SEMATECH]
desiccator n		a tightly closed container charged with a suitable desiccant (commonly calcium chloride or sulfate) that allows an atmosphere of low humidity to be maintained. [SEMI C1-94]
design drawing		see composite drawing.
design environment n		a collection of specific tools, hardware, operating systems, methods, assumptions, capabilities, and procedures used in a design process. [1994 National Technology Roadmap for Semiconductors]
design flow management n		the ability to define a design process that reflects the flow of applications that must be correctly traversed before a design can be released to manufacturing. [1994 National Technology Roadmap for Semiconductors]
design flow rate n		in flow limiting devices, the maximum flow rate exiting a gas cylinder valve when the valve is in a fully open position. All flow rates are given in standard liters per minute (slpm). [SEMI S5-93]
design for test (DFT) n		design of logic circuits to facilitate electrical testing. [SEMATECH]
design methodology n		a comprehensive set of specific engineering rules, methods, and procedures that are used to design and implement integrated circuits, subsystems, or systems. [1994 National Technology Roadmap for Semiconductors]
design metrics		see metrics, design.
design of experiments (DOE) n		the initial planning of engineering experiments in order to minimize cost, reduce experimental errors, and ensure statistical validity of the results. [SEMATECH]
design pressure n		of a system or subsystem, the pressure at the most severe condition of coincident internal or external pressure and temperature expected during normal service. The maximum pressure expected in any portion of a system or subsystem is typically determined by the maximum adjustable setting of the last pressure regulator that supplies it, the supply pressure to the regulator, or the actuation pressure of any relief device incorporated. [SEMI F1-90]
design process n		the flow between computer-aided design (CAD) applications from a user perspective. In today's systems, this flow tends to be sequential with each application processing the entire design model, and, when complete, the changed design model is then processed by the next (sequential) application within the design process. Concurrence in the design process allows for multiple applications (for example, a floor-planner and a timing analysis application) to operate on the design within the same active session. Incremental processing is the art of performing design analysis only on the changed portion of the design (thus the processing time is proportional to the size of the design change and not the entire design). [1994 National Technology Roadmap for Semiconductors]
design representation n		a collection of data in specific formats used to completely characterize a design at a specific level of abstraction. [1994 National Technology Roadmap for Semiconductors]
design reuse n		applying elements of an existing design to the solution of a new problem. [1994 National Technology Roadmap for Semiconductors]
design rules n		rules that state the allowable dimensions of features used in the design and layout of integrated circuits; rules unique to a specific process technology (including limits for feature size, feature separation, layer-to-layer overlap, and layer-to-layer feature separation). [SEMATECH]
design rule check n		a check that a specific integrated circuit design complies with the constraints imposed by the specific technology to be used for its manufacture. [1994 National Technology Roadmap for Semiconductors]
design space n		the set of possible designs and design parameters that meet a specific product requirement. Exploring design space means evaluating the various design options possible with a given technology and optimizing with respect to specific constraints such as power or cost. [1994 National Technology Roadmap for Semiconductors]
design tools		Software tools used to complete the design of integrated circuit (or other) functions. The collection of all tools required to complete the design of an integrated circuit. [1994 National Technology Roadmap for Semiconductors]
design tool		Software tools used to complete the design of integrated circuit (or other) functions. The collection of all tools required to complete the design of an integrated circuit. [1994 National Technology Roadmap for Semiconductors]
developer n		1 : equipment that uses liquids to remove exposed positive resist from wafers or substrates. [SEMATECH] 2 : the liquid used to remove exposed positive resist. [SEMATECH]
develop inspect (D/I)		see linewidth, PR.
device n		a specific kind of electronic component (such as an MOS transistor, resistor, diode, or capacitor) on a die. The diode and transistor are referred to as active devices; the capacitor and resistor, as passive devices. [SEMATECH]
device series of masks		see masks, device series of.
device ID n		in message transfer, a 15-bit field used in the header or message header to identify a piece of equipment communicating with a host computer. NOTE-The value in this field can be in the range of 0 through 32767. [SEMI E4-91]
device pattern n		for reclaimed wafers only, the circuit pattern manufactured on a silicon wafer by a semiconductor manufacturer. [SEMI M8-84]
devitrification n		in flat panel display substrates, a crystalline glass inclusion, similar to stone. [SEMI D9-94]
dew point n		the temperature at which liquid first condenses when vapor is cooled. [SEMI C3-94]

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