Glossary of ESD and Static Control Terms:
Air Conductivity - The ability of air to conduct (pass) an electric current under the influence of an electric field.
Air Ion - A molecular cluster of about 10 molecules (water, impurities, etc.) bound by polarization forces to a singly charged oxygen or nitrogen molecule. Air Ionizer - A source of charged air molecules (ions).Ankle Strap - See Ground Strap.Antistat, Agent - A substance that is part of or topically applied to a material to render the material surface static dissipative or less susceptible to triboelectric charging.Anti-static - Usually refers to the property of a material that inhibits triboelectric charging. Note: A material's antistatic characteristic is not necessarily correlatable with its resistivity or resistance.
Auxiliary Ground - A Separate supplemental grounding conductor for use other than general equipment grounding, that is bonded to the equipment grounding conductor.
Barrier Strip - A device or apparatus that consists of a metal strip and connectors or screws that allow termination and connection of wires or conductors from various components of an electrostatic discharge protected workstation. (See Bus Bar)
Bond or Bonding - The permanent joining of metallic parts to form an electrically conductive path that will assure electrical continuity and the capacity to safely conduct any current likely to be imposed.
Bonding conductor - the connection between two isolated conductors
Bus Bar - A metal strip or bar to which several conductors may be bonded.
Charge Induction - The displacement of charge in an isolated conductor when placed in an electric field (for example, from a charged body). Note: Momentary grounding of such a conductor would result in its gaining a net charge.
Charged Device Model - A specified circuit characterizing an electrostatic discharge which results when a device isolated from ground is first charged and then subsequently grounded.
Cold Healing - The spontaneous recovery, at room temperature, of an item from a parametric change caused by electrostatic discharge.
Cold Workstation - A work area that has items, assemblies, black boxes, or systems to which no power is applied.
Common Point Ground - (1) A grounded device where two or more conductors are bonded. (2) A system or method for connecting two or more grounding conductors to the same electrical potential.
Component - An Item such as a resistor, diode, transistor, integrated circuit and hybrid.
Component Failure - A condition in which a tested component does not meet one or more specified static or dynamic data sheet parameters.
Compressed Gas Ionizer - ionization devices used to simultaneously neutralize charged surfaces and remove surface particles with high pressure gas. This type of ionizer may be used to ionize the gas within production equipment.
Conductive Material - A material that has a surface resistivity less than 1 x 105 ohms/square or a volume resistivity less than 1 x 104 ohm-cm.
Conductivity - 1. The ratio
of the current per unit area
(current density) to the
electric field in a material.
Conductivity is expressed
in units of siemens/meter.
2. In non-technical usage,
the ability to conduct current.
Decay Rate - The decrease of charge or voltage per unit time.
Decay Time - The time required
for an electrostatic potential
to be reduced to a given
percentage (usually 10%)
of its initial value. (See
Voltage - The electric potential
across an insulating material
that causes a sudden increase
in current through the material
of the insulator.
Discharge Time - The time
necessary for a voltage (due
to an electrostatic charge)
to decay from an initial
value to some arbitrarily
chosen final value.
Dynamic Parameters - Those measured with the component in a functioning condition, and may include, but are not limited to: full functionality, output rise and fall times under a specified load condition, and dynamic current draw.
EED - Electrically Explosive Device
Electric Charge - An absence or excess of electrons.
Electrical Ionizer - A device that creates ions in gases by use of high voltage electrodes.
Electrification Period - The average of five electrification times, plus five (5) seconds.
Electrification Time - The time for the resistance measuring instrument to stabilize at the value of the upper resistance range verification fixture.
electrostatic Damage- Change
to an item caused by an electrostatic
that makes it fail to meet
one or more specified parameters.
electrostatic Discharge Control - see Static Control
electrostatic Discharge Ground - The point, electrodes, bus bar, metal strips, or other system of conductors that form a path from a statically charged person or object to ground.
electrostatic Discharge Protected Area - A designated environment provided with materials and equipment to limit electrostatic potentials.
electrostatic Discharge Protective - A property of materials capable of one or more of the following: reducing the generation of static electricity, dissipating an electrostatic charge, or providing shielding from electrostatic discharge or electrostatic fields.
electrostatic Discharge Protective Workstation - An area that is constructed and equipped with the necessary protective materials and equipment to limit damage to electrostatic discharge susceptible items handled therein.
electrostatic Discharge Protective Worksurface - A worksurface that dissipates electrostatic charge from materials placed on the surface or from the surface itself.
electrostatic Discharge Sensitivity (ESDS) - The electrostatic discharge level that causes component failure.
electrostatic Discharge Shield - A barrier or enclosure that limits the passage of current and attenuates an electromagnetic field resulting from an electrostatic discharge.
electrostatic Discharge Spark Testing - Testing performed with operating equipment or parts to determine their susceptibility to the transient electromagnetic fields produced by an air discharge event.
(ESDS) - The propensity to
be damaged by electrostatic
electrostatic Discharge Susceptibility Symbol - The graphics placed on hardware, assemblies, and documentation for identification of electrostatic discharge susceptible items.
electrostatic Discharge Susceptible Item - Electrical or electronic piece part, device, component, assembly, or equipment item that has some level of electrostatic discharge susceptibility.
electrostatic Discharge Withstand Voltage - The maximum electrostatic discharge level that does not cause component failure.
electrostatic Field -An attractive or repulsive force in space due to the presence of electric charge.
electrostatic Potential - The voltage difference between a point and an agreed-upon reference.
electrostatic Shield - A barrier or enclosure that limits the penetration of an electrostatic field.
Electrostatics - The study of electrostatic charge and its effects.
Emitter - A conducting sharp object, usually a needle or wire, which will cause a corona discharge when kept at a high potential.
EOS - See Electrical Overstress.
Equipment Ground - 1. The
ground point at which the
equipment grounding conductor
is bonded to any piece of
equipment, at the equipment
end of the conductor. 2.
The 3rd wire (green) terminal
of a receptacle. 3. The entire
low impedance path from a
piece of electrical equipment
to a hard ground electrode.
ESD - See electrostatic
ESD Sensitivity - See electrostatic discharge susceptibility.
ESD technical element - All of the devices, equipment, materials and tools that make up an EPA for ESD control
See electrostatic discharge
Failure model - several
different models have been
to identify the way an ESD
event can damage or destroy
a device. The three most common
failure models are the charge
device model (CDM), the human
body model (HBM) and the machine
Faraday Cage - A conductive enclosure that attenuates a stationary electrostatic field.
Field Induced Charging - A charging method using electrostatic induction.Foot Grounder - A ground strap used for mobility that connects the bodies foot to ground (ESD floor) via a conductive tab between the sock and insole connected to a conductive outer wear (rubber cup) that is positioned on the bottom sole of the shoe. Foot grounders come in different styles: heel grounders, toe grounders, ball (of the foot) grounders and sole (combination heel and ball) grounders.
Foot strap - see Foot Grounder.
1 GigOhm - 1E09 or 1 thousand Meg ohms
Ground - 1.A conducting connection,
or accidental between an
electrical circuit or equipment
and the earth, or to some
conducting body that serves
in place of earth. 2. The
position or portion of
an electrical circuit at
zero potential with respect
to the earth. 3. A conducting
body, such as the earth
or the hull of a steel
ship, used as a return
path for electric currents
and as an arbitrary zero
Ground Strap - 1.A conductor
intended to provide an electrical
path to ground. 2. An item
used by personnel with a
specified resistance, intended
to provide a path to ground.
Grounded Conductor - A system or circuit conductor that is intentionally grounded.
Grounded - Connected to earth or some other conducting body that serves in place of the earth.
Grounding Conductor - A conductor used to connect equipment or the ground circuit of a wiring system to a ground electrode or electrodes.
Grounding Resistance - The total resistance from any given point in an electrically conductive path to the grounding electrode.
Hard Ground - A connection to ground through a wire or other conductor that has very little or nearly no resistance (impedance) to ground.
Horizontal Laminar Flow - Non-turbulent air flow in a horizontal direction.
Hot Workstation - A work
area that has items, assemblies,
black boxes, or systems,
which have power applied
for testing or repair.
Human Body Model electrostatic Discharge - An electrostatic discharge event meeting the waveform criteria specified in ANSI/EOS/ESD-S5.1-1993, approximating the discharge from the fingertip of a typical human being.
Human Body Model
Tester - Equipment
that applies Human Body Model
to a component.
Impedance - n. Symbol Z A measure of the total opposition to current flow in an alternating current circuit, made up of two components, ohmic resistance and reactance, and usually represented in complex notation as Z = R + iX, where R is the ohmic resistance and X is the reactance. Impedance is measured in ohms.
Inductive Charging - The transfer of an electric charge to an object when it is momentarily contacted to ground in the presence of an electric field.
Input Protection - Structures,
devices or networks connected
at the input terminals of
an item to prevent electrostatic
Insulative Material - A material having a surface resistivity of at least 1 x 1012 ohms/square or 1 x 1011 ohm- cm volume resistivity.
Ionization - The process
by which a neutral atom or
molecule acquires a positive
or negative charge.
Ionizer - A device which is designed to generate positive and/or negative air ions.
Isolated Conductor - A non-grounded conductor.
Isolated Ground Receptacle - A grounding type receptacle in which the equipment grounding conductor contact and terminal are electrically isolated from the receptacle mounting means.
Junction Damage - Electrical Overstress damage to a semiconductor junction.
Laminar Flow Hood Ionization - These devices or systems provide local area ionization coverage in vertical or horizontal laminar flow hoods or benches.
Latent Failure - A malfunction that occurs following a period of normal operation. Note: The failure may be attributable to an earlier electrostatic discharge event. The concept of latent failure is controversial and not totally accepted by all in the technical communityLow charging - refers to the low static charge generation between surfaces that contact and separate. This term has replaced the word "antistatic."
Machine Model - An electrostatic discharge simulation test based on a discharge network consisting of a charged 200 picofarad capacitor and (nominally) zero ohms of series resistance. Actual series resistance and inductance are specified in terms of the current waveform through a shorting wire. The simulation test approximates the electrostatic discharge from a machine.
Machine Model electrostatic Discharge - An event meeting the criteria specified in ESD-S5.2-1994.
Main Bonding Jumper - The connection between the grounded circuit conductor and the equipment grounding conductor at the service.
Monitor, Charge(d) Plate - An instrument used to measure the charge neutralization properties of ionization equipment.
Neutralize - To eliminate an electrostatic field by recombining positive and negative charges, either by conducting the charge to ground or by introducing an equal opposite charge.
Nuclear Ionizer - A device that creates ions usually by alpha emissions which strip electrons from gas molecules to form equal numbers of positive and negative ions in gases.
Offset Voltage - The observed
voltage on the isolated conductive
plate of a charged plate
monitor that has been placed
in an ionized environment.
Oxide Punch-through - Dielectric breakdown of an oxide layer, as in a semiconductor device.
Plasma - A highly ionized gas. The fourth state of matter (it does matter). 99% of all matter in the universe is in a plasma state. Lightning, neon lights and fire are natural examples of plasma on Earth.
Paschen's Law - The sparking potential between two terminals in a gas is proportional to the pressure times the spark length. For a given voltage, this means the spark length is inversely proportionate to the pressure.
Passive Ionizer - A device, usually a sharp grounded needle point, that discharges surfaces in the immediate vicinity by creating a conductive path of air ions.
Peak Offset Voltage - For pulsed ionizers, the maximum value of the offset voltage for each polarity, as the ionizer cycles between positive and negative ion outputs.
Personnel Grounding Device - An electrostatic discharge protective device designed to ground any electrostatic charge accumulated on a person. NOTE: The resistance to ground of a personnel grounding device must be high enough to avoid causing an electrical shock hazard.
Planar Material - An item with a surface sufficiently large and flat to conform to the surface resistance measuring electrode described in EOS/ESD-S11.11-1993.
Q - Symbol for quantity of electrical charge.
Quality Control - The control of variation of workmanship, processes, and materials in order to produce a consistent, uniform product.
rms - The "root-mean-square" value
of ac voltage, current, or
power. Calculated as 0.707
of peak amplitude of a sine
wave at a given frequency.
Service Equipment - The necessary equipment, usually consisting of a circuit breaker or switch and fuses, and their accessories, located near the point of entrance of supply conductors to a building or other structure, or an otherwise defined area, and intended to constitute the main control and means of cutoff of the supply.
Shielding - an electrostatic field radiates in the area surrounding most charged objects. This field can produce an ESD event or inductively charge other objects nearby and produce undesirable results. A conductive, grounded enclosure, such as a Faraday cage, that completely surrounds an object will shield the contents within from the effects of an external electrostatic field. A metallized bag or a conductive tote box are examples of shielding.
Shunting Bar - A device
that shorts together the
terminals of an electrostatic
discharge susceptible item
forming an equipotential
surface. Spark - An electrical discharge
of very short duration, normally
between two conductors separated
by a gas (such as air).
Surface Resistance - The
ratio of DC voltage to the
current flowing between two
electrodes of specified configuration
that contact the same side
of a material. This measurement
is expressed in ohms.
Tests - Daily
Topical Antistat - An antistat that is applied to the surface of a material for the purpose of making the surface static dissipative or to reduce triboelectric charging.
Triboelectric Charging - The generation of electrostatic charges when two materials make contact or are rubbed together, then separated. (See also Triboelectric series.)
Triboelectric Series - A list of materials arranged so that one can become positively charged when separated from one farther down the list, or negatively charged when separated from one farther up the list. Note: The series' main utility is to indicate likely resultant charge polarities after triboelectric generation. However, this series is derived from specially prepared and cleaned materials tested in very controlled conditions. In everyday circumstances, materials reasonably close to one another in the series can produce charge polarities opposite to that expected. This series is only a guide.
Vertical Laminar Flow - Non-turbulent air flow in a vertical direction.
Voltage Suppression - Reduction of the voltage (V) of a charged object by increasing its capacitance (C) rather than by decreasing its charge (Q), in accordance with the formula V = Q/C. Note: Voltage suppression typically occurs when a charged object is brought closer to ground.
Volume Resistivity rv) - The ratio of the DC voltage per unit thickness to the amount of current per unit area passing through a material. Volume resistivity is given in ohm-centimeters.
Worksurface Groundable Point - A point on the worksurface that is intended to accommodate an electrical connection from the worksurface to an appropriate electrical ground.
ionization devices or systems
used to control static charges
at a work station. Note:
This type includes benchtop
ionizers, overhead worksurface
ionizers, and laminar flow
Zap - (colloquial term) See electrostatic discharge.
Copyright 2004-2013 Ground Zero Electrostatics, Inc. Ground Zero Electrostatics is an employee owned company and is an equal opportunity employer.