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

"Ste-Sz"

steam atmosphere n		the atmosphere in a heated, closed vessel containing water, with sufficient venting so that a temperature of 100 degrees +0, -5 degrees C is maintained at one (1) standard atmosphere. Steam atmosphere is used to accelerate surface aging characteristics during lead solderability testing. [SEMI G35-87]
steam bath n		exposure to flowing steam or to another source of heat at the temperature of flowing steam, at one atmosphere pressure. [Adapted from SEMI C1-94]
step n		1 : a single action in the performance of an operation, procedure, or process. [SEMATECH] 2 : the transitions from lower levels of a wafer pattern to upper layers; the topography of a patterned wafer. [SEMATECH]
step and repeat n		an operation that, by the use of a stepper, repeats the image over the wafer as the stage makes small steps in the X and Y axes. The operation dimensionally positions multiples of the same or intermixed functional patterns on a given area of a photoplate or a film by repetitions, contact printing, or projection printing of a single original pattern of each type. [SEMATECH]
step coverage n		the ratio of thickness of film along the walls of a step to the thickness of the film at the bottom of a step. Good step coverage reduces electromigration and high-resistance pathways. [SEMATECH]
step function transient response n		in regulator performance testing, a plot of outlet pressure versus time when switching between two flow rates. [SEMATECH]
step response time n		in mass flow controller testing, the time between the set point step change and the moment the actual flow first enters the specified band. [SEMI E17-91]
step stress test n		a test that consists of several stress levels applied sequentially for periods of equal duration to a sample. During each period, a stated stress level is applied, and the stress level is increased from one step to the next. (Copyright 1993 IEEE. All rights reserved.)
stepper n		equipment used to transfer a reticle pattern onto a wafer. [SEMATECH]
STM		see scanning tunneling microscope.
stoichiometric adj		describes a quantitative relationship, usually expressed as the ratio between two or more chemical substances undergoing a physical or chemical change; the point at which the chemical reaction ends or stabilizes. [SEMATECH]
storage temperature limits n		in a mass flow controller, the temperature limits to which the device may be subjected in an unpowered condition. No permanent impairment will occur, but minor adjustments may be needed to restore performance to normal. [SEMI E18-91]
streak n		in the surface roughness measurement of flat panel display glass substrates, a defect whose appearance is a transparent line on the glass substrate surface. A streak can be caused by either a microsurface discontinuity or a cord, due to the heterogeneity of glass composition. [SEMI D9-94]
stream n		in SECS communication, a category of messages intended to support similar or related activities. NOTE-A specific message for a specific activity within a stream is called a function. [SEMI E5-92].
street		see scribe line.
stress marks n		thin, radial lines that start in the center of a photoplate and extend outward. The lines are colored. [SEMI P3-90]
stress test n		exposure of components to extreme mechanical, temperature, humidity, and biased conditions. [SEMATECH]
striation n		1 : a helical feature on the surface of a silicon wafer associated with local variations in impurity concentration. [ASTM F1241] 2 : a poor resist coat caused by separation of the chemical compounds of the resist. [SEMATECH]
stripper n		a chemical solvent used to remove resist film from wafers. [SEMATECH]
stripping n		an operation that completely removes a resist coating. [SEMATECH]
stripping solution n		a chemical mixture that will remove either processed or unprocessed resist from its substrate. [ASTM F127-84]
stuck-at fault n		a fault in a manufactured circuit causing an electrical node to be stuck at a logical value of 1 or a logic value of 0, independent of the input to the circuit. [1994 National Technology Roadmap for Semiconductors]
stylus method surface roughness measuring instrument n		in the roughness measurement of flat panel display substrate surfaces, an instrument that traces on a section of a surface with a stylus, records irregularity on the surface in an enlarged form, and indicates irregularity amplitude as roughness parameters. [SEMI D7-94]
subdiffused layer		see buried layer.
sub-fab n		the area located underneath the processing floor of the fab that contains support equipment (pumps, etc.) for processing tools. [SEMATECH]
subject v		to expose to or apply. [SEMI F12-93]
submersion container n		in fluid distribution systems, a transparent container filled with a low surface tension fluid at 23 ±3 degrees C, used for observing leakage. [SEMATECH] Also called submersion tank.
submersion tank		see submersion container.
submicrometer process n		a sequence of steps that produces integrated circuits that have line widths (critical dimensions) of less than 1 micrometer. [SEMATECH]
submittals n		technical data about a specific product or system; a method that allows contractors to verify the design intent prior to purchase or construction. [SEMATECH]
substrate n		in the manufacture of semiconductors, a wafer that is the basis for subsequent processing operations in the fabrication of semiconductor devices or circuits. [ASTM F1241]
subsystem n		an assembly of two or more components that is manufactured as a single entity. A subsystem must be combined with one or more additional components or subsystems to form a complete system. [SEMI F1-90]
sulfur hexafluoride (SF6) n		a colorless and odorless gas that has a low toxicity. Sulfur hexafluoride is used as a plasma etchant and as an etchant before chemical vapor deposition. [SEMI C3.24-90] Also see dry plasma etch.
sulfuric acid (H2SO4) n		a strong, poisonous, corrosive liquid that will mix with water and that will dissolve most metals. Sulfuric acid is used to clean wafers and to remove resist. [SEMI C1.16-90]
supplier-dependent uptime n		the percentage of time that the equipment is in a condition to perform its intended function during the period of operations time minus the sum of user maintenance delay, out-of-spec input downtime, and facilities related downtime. This calculation subtracts only user maintenance delay from the period, thereby taking into account supplier delays for parts and service. [SEMI E10-92] Also see equipment states.
supply pressure effect n		in determining regulator performance characteristics, the effect of an inlet pressure change on the outlet pressure of a regulator. [SEMATECH]
support tool n		a mechanical device that, although not a part of a piece of equipment, is required by it and becomes integral with it during the course of normal operation. Examples include wafer carriers, boats, and probe cards. [SEMI E10-92]
surface n		1 : the boundary that separates an object from another object, substance, or space. [ASME B46.1-85] 2 : in electron spectroscopy for chemical analysis (ESCA), that volume from which the photoelectrons can escape. [SEMATECH]
surface area index n		in determining surface roughness by contact profilometry or scanning tunneling microscopy, the area of a best fit plane (or ideal surface) subtracted from the actual area calculated for the surface, divided by the ideal area, and multiplied by 1,000. [SEMATECH]
surface chip		see peripheral chip.
surface contamination n		in flat panel display substrates, an area that is contaminated with organic or inorganic material. [SEMI D9-94]
surface defects n		1 : in the manufacture of silicon on sapphire (SOS) epitaxial silicon wafers, mechanical imperfections, SiO2 residual dust, and other imperfections visible on the wafer surface. Some examples of surface defects are: dimples, pits, particulates, spots, scratches, smears, hillocks, and polycrystalline regions. [SEMI M4-88] 2 : in flat panel display substrates, a marking, tearing or single line abrasion on the glass surface. [SEMI D9-94]
surface imaging n		multilayer resists on which the image to be transferred is focused onto a thin resist layer on the surface when developed. This thin layer serves as a mask to pattern a thick resist layer that is employed for forming the image on the wafer. [1994 National Technology Roadmap for Semiconductors]
surface micro defect		see crystal originated particle.
surface profile n		the contour of the surface in a plane perpendicular to the surface, unless some other angle is specified. [ASME B46.1-85]
surface protrusions or intrusions n		in the manufacture of molded plastic packages, plastic excesses (such as bumps or blisters) or recesses (such as pits or voids) on any surface of the package. [SEMI G54-93]
surface roughness n		the finer irregularities of the surface texture, usually including those irregularities that result from the inherent action of the production process. Examples include traverse feed marks and other irregularities within the limits of the roughness sampling length. [ASME B46.1-85]
surface texture n		the topographic deviations of a real surface from a reference surface. NOTE-Surface texture includes roughness, waviness, and lay. [ASTM F1241]
surrogate gas n		in the calibration of mass flow devices, a gas intended to simulate the calibration characteristics of another gas. [SEMI E29-93]
surround shape n		a geometric configuration around the symbol, which can convey additional safety information. [SEMI S1-90]
swab bud n		in determining surface associated biofilm, the portion of a swab that makes contact with the sample, as distinct from the handle. [SEMATECH]
SWIM n		a software system and data infrastructure that allows manufacturing modeling applications and CIM systems to be integrated in a common framework. A primary capability of SWIM is that it supports the transfer of common data between the referenced applications and systems. Through its task manager, SWIM also provides utilities that facilitate modeling analysis. Abbreviation for semiconductor workbench for integrated modeling. [SEMATECH]
swirl n		helical or concentric features that are visible to the unaided eye after preferential etch and appear to be discontinuous under 100X magnification. [ASTM F1241]
symbol n		1 : a graphic representation, either abstract or representational, of a hazardous situation and/or evasive actions to be taken to avoid harm. It may include a description of protective equipment to be used to eliminate or reduce the hazard to an acceptable level. [SEMI S1-90] Also see sign. 2 : in the bar code marking of silicon wafers, a combination of characters, including start/stop characters, quiet zones, data characters and check characters, that are required by a particular symbology and that form a complete scannable entity. [SEMI T1-93]
symmetrical valve n		a valve bilaterally identical with respect to its center line and having similar flow and pressure characteristics in either direction. [SEMATECH]
symptom n		a subjective indication of a disease or of a change in condition as perceived by the person. [SEMATECH]
synthesis design n		the automatic or semiautomatic creation or refinement of a design at a given level of abstraction; for example, local synthesis, layout synthesis, etc. [1994 National Technology Roadmap for Semiconductors]
synthesis for testability n		the synthesis of logic from a higher level description incorporating considerations to ensure that the final design can readily be tested. [1994 National Technology Roadmap for Semiconductors]
system n		1 : an integrated whole, composed of diverse, interacting, specialized structures and subfunctions. [SEMATECH] 2 : an integrated structure of components and subsystems capable of performing, in aggregate, one or more specific functions. [SEMI F1-90]
system architecture		see architecture.
system bytes n		a 4-byte field in a header; used for message identification. [SEMI E4-91]
system default n		in communications and control of semiconductor manufacturing equipment, a state or states in the equipment behavioral model that are expected to be active at the end of system initialization, and the value or values that specified equipment variables are expected to contain at the end of system initialization. [SEMI E30-94]
systemic effects (SYS) adj		describes effects on the metabolism and excretory functions. [SEMATECH]
system initialization n		in communications and control of semiconductor manufacturing equipment, the process that an equipment performs at power-up, system activation, and/or system reset. This process is expected to prepare the equipment to operate properly and according to the equipment behavioral models. [SEMI E30-94]

Back to index…