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

"R"

radial cluster tool n		a cluster tool in which all wafer transport axes intersect at a common point within the transport module. [SEMI E26-91]
radical n		a chemical fragment of a larger molecule. [SEMATECH]
radio frequency (RF) n		electromagnetic energy with frequencies ranging from 3 kHz to 300 GHz. Microwaves are a portion of radio frequency extending from 300 MHz to 300 GHz. [SEMI S2-93]
radiometer n		an instrument for measuring the intensity of radiant energy. [ASTM E1316-94]
ram follower n		a transducer device used to measure the linear movement or velocity of a mold press transfer ram. Using this device, the flow characteristics of a molding compound may be measured. In particular, the gel time may be measured. [SEMI G11-88] Also see spiral flow.
ramp-down n		the portion of a maintenance procedure required to prepare the equipment for hands-on work. It includes purging, cool-down, warm-up, etc. Ramp-down is included only in scheduled and unscheduled downtime. [SEMI E10-92] Also see equipment downtime.
ramp-up n		the portion of a maintenance procedure required, after the hands-on work is completed, to return the equipment to a condition in which it can perform its intended function. It includes pumpdown, warm-up, stabilization periods, initialization routines, etc. It does not include equipment or process test time. Ramp-up is included only in scheduled and unscheduled downtime. [SEMI E10-92] Also see equipment downtime.
random access memory (RAM) n		data storage that can be read from, and written to, arbitrary locations in arbitrary sequence. [SEMATECH]
random logic device n		a semiconductor device that contains an interconnected array of dissimilar function blocks, such as memory, registers, arithmetic logic unit, and bus interface unit. Examples are the microcomputer and the microprocessor. [SEMATECH]
range n		the region between the limits within which a quantity is measured, expressed by stating the lower and upper range values. [SEMI E27-92]
rapid thermal annealing (RTA)		see rapid thermal processing.
rapid thermal processing (RTP) n		a process in which a wafer is heated to a specified temperature for short periods of time. When referring specifically to annealing processes, the process is called rapid thermal annealing (RTA). [SEMATECH]
rare gas n		any of the six gases, all noble, comprising the extreme right-hand group of the Periodic Table; namely helium, neon, argon, krypton, xenon, and radon. [SEMI C3-94]
raster n		the movement or area defined by repetitively scanning (with a microscope) in the X-direction while moving stepwise in the Y-direction. [SEMATECH]
rated pressure n		the manufacturer's recommended maximum allowable operating pressure at the manufacturer's rated temperature. [SEMI F1-90]
rated pressure n		the manufacturer's recommended maximum allowable operating pressure at the manufacturer's rated temperature. [SEMI F1-90]
rated pressure n		the manufacturer's recommended maximum allowable operating pressure at the manufacturer's rated temperature. [SEMI F1-90]
reach n		the distance measured from the interface plane to the wafer centroid (center of mass) within a process module or a cassette module of a cluster tool. [SEMI E21-94]
reactive ion etch (RIE) n		a dry-etch process using electrical discharge to ionize and induce ion bombardment of the wafer surface to obtain the required etch properties. [SEMATECH]
reactivity n		the tendency of a substance to undergo chemical reaction, either by itself or with other materials, and to release energy. [SEMATECH]
reactor n		a sealed isolation chamber in which a reaction occurs. [SEMATECH]
Ready to Receive		see EOT.
reagent n		in the semiconductor industry, a chemical that is suitable for use in the manufacture of semiconductors or in the performance of chemical tests. The purity of a reagent solution is higher than the purity of a standard solution. [SEMATECH]
real time n (adj real-time)		pertaining to a system designed to control a dynamic process within the timing constraints of the process. [SEMATECH]
receiver n		the end of the SECS-I link receiving a message. [SEMI E4-91]
receiving port n		in an automated material transfer, the port into which a transfer object is to be placed. [SEMI E32-94]
recipe n		the computer program, rules, specifications, operations, and procedures performed each time to produce a wafer that contains functional die. Examples are the setup recipe and the process recipe. [SEMATECH]
reclaim test wafer		see wafer, reclaim test.
reference ambient n		in a mass flow controller, the composition and pressure range of the ambient medium surrounding the device within which performance specifications apply without requiring correction for changes in the ambient medium. [SEMI E28-92]
reference operating pressure, inlet and outlet n		in a mass flow controller, the range of gas pressures on the inlet of the device and across the device within which performance specifications apply without requiring correction for gas pressure effects. [SEMI E28-92]
reference operating temperature n		in the temperature specifications of mass flow controllers, the range within which accuracy statements apply without requiring correction for temperature effects. [SEMI E18-91]
reference plane n		in semiconductor technology, a plane defined by one of the following: three points at specified locations on the front surface of a wafer; the least squares fit to the front surface of a wafer using all points within the fixed quality area (FQA); the least squares fit to the front surface of a wafer using all points within a site; or an ideal back surface (equivalent to the ideally flat chuck surface that contacts the wafer). [SEMI M1-94]
referent n		the message intended to be associated with the symbol. [SEMI S1-90]
reflectometer n		equipment used to measure the reflectance or cloudiness of a metal. [SEMATECH]
reflectometry n		a technique for measuring reflectance or the reflectance factor. [ASTM E284-94]
refractive index n		the ratio of the velocity of light in the first of two media to its velocity in the second as it passes from one into the other. The first medium is usually a vacuum. [SEMATECH]
refractory metallization n		a high melting point metal, usually tungsten or a mixture of similar metals in paste form, which is screen printed onto unfired ceramic sheets (green sheets) in order to produce metallized areas in cofired ceramic packages. [SEMATECH]
regenerant n		in the ionic contamination testing of semiconductor leadframes, a chemical solution containing the ions originally present in the chromatograph column prior to a test run, used to prepare the column for a new test. [SEMI G59-94]
register transfer level (RTL) n		a circuit description that involves describing the circuit in terms of storage registers and sequence of transfers of data between the registers. [1994 National Technology Roadmap for Semiconductors]
registration n		1 : the accuracy of the relative position of all functional patterns on any reticle with the corresponding patterns of any other reticle of a given device series when the reticles are properly superimposed. [ASTM F127-84] 2 : a vector quantity defined at every point on the wafer. It is the difference, R, between the vector position, , of a substrate geometry and the vector position of the corresponding point, , in a reference grid. [SEMATECH] 3 : in the overlay capabilities of wafer steppers, a vector quantity defined at every point on the wafer. It is the difference, R, between the vector position, , of a substrate geometry, and the vector position of the corresponding point, , in a reference grid. [SEMI P18-92]
registration holes n		holes in the bottom of the box door that fit over registration pins in the top of the port door when the box is placed on the port door. [SEMI E19.4-94]
registration pins n		pins that provide fixed position and orientation between the port door and box door and assist in final positioning of the box on the port assembly. The registration pins fit into the registration holes in the bottom of the box door. [SEMI E19.4-94]
regulated material, other		see other regulated material.
regulator n		a valve designed to reduce a high incoming pressure (for example, from a cylinder) to a lower outlet pressure by automatically opening to allow flow until a desired, preset pressure on the outlet side is reached and then automatically throttling closed to stop further pressure increase. [SEMI International Standards 1990, Vol. 1, Glossary]
regulator isolation valve n		a valve located between a purge manifold and a system regulator to separate, when closed, the regulator from the purging process, thereby maintaining the undiluted purity of the gas in the regulator. [SEMI Chemicals/Gases, Vol. 1, 1990 (no longer in print)]
relative humidity (RH) n		the quantity of water vapor present in the atmosphere as a percentage of the quantity that would saturate at the existing temperature. [SEMATECH]
relative minimum n		in optics, a minimum in the amount of light transmitted through a polarizer and analyzer combination that results when either the polarizing angle or the analyzing angle is varied (with the other angle fixed). [ASTM F1241]
reliability n		of equipment, the probability that the equipment will perform its intended function, within stated conditions, for a specified period of time. [SEMI E10-92]
relief valve n		a pressure-relieving device, installed in a line or control component, designed and adjusted to release pressure that could damage other components in the system. [SEMI International Standards 1990, Vol. 1, Glossary]
reply n		the particular second message of a transaction sent in response to the first message of the same transaction. NOTE-The reply is the secondary message; the first message is the primary message. [SEMI E4-91 and E5-92] Contrast primary message.
reply linking n		the process of forming a transaction from a primary message and a secondary message. NOTE-A primary message is the first message of a transaction, and a secondary message is the second. [SEMI E4-91]
reportable quantity (RQ) n		the quantity of material that, when spilled, must be reported to the appropriate authority. [SEMATECH]
repository n		1 : a database system with services for storing all types of data objects such as documents, CASE diagrams, and interrelationships between such objects, allowing a user to locate, check out, display, edit, and check in these objects. A repository maintains the consistency of these objects according to user-defined rules during concurrent access and manipulation. [SEMATECH] 2 : a system for storing and accessing information. [SEMATECH] 3 : a data service that provides a mechanism for the consistent and shared use of data among a set of applications. It is an important means by which the applications can be properly integrated. The set of applications will be broadened over time. [SEMATECH] 4 : the database containing the complete set of information including the models describing the system, the processes, and the environments in which it is produced and in which it will operate. Repository data and information is accessible to users through more than one interface and through more than one level of abstraction. [SEMATECH]
request for information (RFI) n		documentation from contractor to the design team to request clarification. [SEMATECH]
Request to Send		see ENQ.
residue n		any undesirable material that remains on a substrate after any process step. [ASTM F127-84 and SEMI P3-90]
residue, solvent		see solvent residue.
residue, wax		see wax residue.
resin bleed n		the seepage of the resin component of plastic molding compounds between the face of a plastic package encapsulation mold and the leadframe surface in contact with the mold. This resin may affect the soldering or plating of the leadframe unless it is removed by chemical or media deflashing. [SEMATECH] Contrast flash.
resist n		a photosensitive liquid-plastic film applied to the surface of a wafer for lithography. [SEMATECH] Also see photoresist.
resistance, chemical n		the ability of a material, such as a resist coating, to withstand chemical attack. [SEMATECH]
resist breakdown adj		describes the excessive removal of metal that occurs when and if the resists used to mask metal in the production of etched leadframes flake off during the etching process. This excess removal is in addition to the undercut normally observed. [SEMATECH] Also see etch factor, leadframe, and undercut.
resist cure n		the process of eliminating undesirable properties of resists. Such properties include tackiness, softness, a tendency to flow, and lack of adhesion. [SEMATECH]
resist edge adhesion		see adhesion, resist edge.
resistivity () n		1 : of a semiconductor, the ratio of the potential gradient parallel with the current in the material to the current density. Units are . [SEMI M4-88] 2 : the resistance that a unit volume of semiconductor material offers to the passage of electricity when the electric current is perpendicular to two parallel faces. [SEMI M1-94] 3 n (electrical) : the measure of difficulty with which charge carriers flow through a material. Resistivity is the reciprocal of conductivity. DISCUSSION-The resistivity of a semiconductor or other material is the ratio of the potential gradient (electronic field) parallel with the current to the current density. [ASTM F1241]
resist lifting n		on a wafer, the loss of adhesion of a resist coating to its substrate. [SEMI P3-90] Also called photo lifting.
resist rings n		on a wafer, buildup of a resist in round, multicolored rings; generated by particles or bubble bursts. [SEMI P3-90]
resolution n		the fineness of detail revealed by an optical device. Resolution is usually specified as the minimum distance by which two lines in the object must be separated before they can be revealed as separate lines in the image. [ASTM E7-90]
resolution, practical n		the minimum linewidth that reproduces the mask (or drafting) dimensions faithfully. [SEMI P25-94]
resolution, usable n		the smallest image that can be produced and subsequently processed in a given thickness of resist coating. [ASTM F127-84]
resolution dagger n		a photolithography tool used to enhance and refine resolution. [SEMATECH]
resonance n		in testing regulator performance characteristics, diaphragm oscillation when the regulator is used under normal conditions. [SEMATECH]
response curve n		relation between the measured scattered light intensity and latex sphere diameter. This curve depends on the used light source and may have nonmonotonic regions. [SEMI M25-94]
response time n		in testing components for contaminant contribution to gas distribution systems, the time required for the system to reach steady state after a measurable change in concentration. [SEMATECH]
retention time n		in the ionic contamination testing of semiconductor leadframes, the time required for a particular ion type to pass from the injection port to the detector. Retention time is characteristically different for each ion type. [SEMI G59-94]
reticle n		a very flat glass plate that contains the patterns to be reproduced on a wafer; the image may be equal to or larger than the final projected image. Typical reticle substrate material is quartz, and typical magnifications are 10, 5, and 1 times final size. The reticle is used in a stepper. [SEMATECH]
reticle eyepiece n		a microscope eyepiece that has as its focal plane a system of lines or other reference marks. [ASTM F127-84]
retrofit n		1 : the modification of a building to incorporate new functions not included in the original building design. [SEMATECH] 2 :the modification of equipment to incorporate changes and improvements in technology as they become available. [SEMATECH]
retry count n		in the block transfer protocol, the number of unsuccessful attempts to send a block. [SEMI E4-91] Also see RTY.
retry count n		in the block transfer protocol, the number of unsuccessful attempts to send a block. [SEMI E4-91] Also see RTY.
return on investment (ROI) n		a SEMATECH calculation of derived member company benefits divided by their costs to obtain those benefits. [SEMATECH]
return to zero n		a digital waveform that undergoes two transitions per clock cycle. [1994 National Technology Roadmap for Semiconductors] Also see non-return to zero.
reverse osmosis (RO) n		a technique used in desalination treatment. Pressure is applied to the saline solution, forcing pure water to pass from the solution through a membrane that will not pass the undesired ions. [SEMATECH]
reverse polarity mask		see photomask, reverse polarity.
RIE		see reactive ion etch.
risk n		an expression of the possibility of a mishap in terms of hazard severity and hazard probability. [SEMI S2-93]
roadmap n		comprehensive forecast in which requirements and actions are described in a time sequence. [SEMATECH]
robot vehicle n		a piece of equipment having a cassette transfer robot on the vehicle, which moves to another piece of equipment and transfers cassettes. [SEMI E23-91]
ROI		see return on investment.
roll back n		a procedure used in file systems and database management systems to restore integrity after an incident. Data changes are made in a nonpermanent way until a complete logical transaction is completed. The changes are then committed; that is, made permanent as a group. If there is a problem, all changes in the logical transaction are deleted; that is, rolled back. [SEMATECH]
rotary concentrator n		equipment that uses a rotating wheel containing zeolite to absorb volatile organic carbon (VOC) emissions from wafer fabrication equipment. The VOCs are are then desorbed by heat and subsequently burned. [SEMATECH]
rotated astigmatism n		in the measurement of photolithographic instruments, at each image site, the Z-axis difference for the line focus of two evaluative line sets, oriented at right angles to each other and at some specified angle to the coordinate system, where the specified angle is selected so that the Z-axis focus difference is a maximum at the given image site. The specified angle may vary from image site to image site. [SEMI P25-94]
rotation n		in dielectrically isolated (DI) wafers, the angle of deviation between the primary flat of the DI wafer and the X axis of the photolithography pattern. [SEMI M22-92]
rotational error n		the error that occurs when functional patterns are misaligned by some angle to the X-X and Y-Y axes during step and repeat. [ASTM F127-84]
roughness n		1 : the more narrowly spaced components of surface texture. DISCUSSION-These components are considered within defined limits of spatial wavelength (or frequency). [ASTM F1241] 2 : in flat panel display substrates, the criterion for the smoothness of the sheet surface. [SEMI D9-94]
roughness average n		in surface profilometry, the arithmetic average of the absolute values of the measure profile height deviations taken within the sampling length and measured from the graphical center line. [ASME B46.1-85]
routing n		the act of connecting all of the nets in an integrated circuit to the ports of the logic elements. Also, the interconnections of the components on a board. [1994 National Technology Roadmap for Semiconductors]
row n		the set of functional patterns that lies along an X-X axis of a photomask. [ASTM F127-84]
RTA or RTP		see rapid thermal processing.
RTL		see register transfer level.
RTY n		the retry limit (RTY), or the maximum number of times that the block transfer protocol will retry sending a block before declaring a failed send. [SEMI E4-91] Also see retry count.
rub n		in flat panel display substrates, a surface scratch or series of small scratches, generally caused during handling. [SEMI D9-94]
rundown n		on a semiconductor package, the linear distance from the upper surface of a ceramic cavity layer to the bottom point of the overhang into the cavity, of a sealing glass or metallization layer that has been screened onto that surface. [SEMI G61-94]
runout		see cumulative pitch error.

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