Acceptor An impurity atom used in the doping process to create a hole in a semiconductor crystal; contains 3 electrons in its outermost valence shell.
Annihilation See recombination.
Anode The P side of a PN junction diode.
Avalanching Large current How through a reverSl,.-~;.:r:~ ~j;, ”’r”’l1 it breaks down: caused by a high electric field imparting high velocities to electrons that then rupture covalent bonus.
Band, energy See energy band.
Barrier diode See Schottky diode.
Barrier potential Potential (voltage) established by the presence of layers of charge lying on opposite sides of a PN junction .
Barrier voltage See barrier potential.
Bias Connection of an external vol age source across a PN junction. See also forward bias and reverse bias.
Boltzmann’s constant (k) . Constant used in the diode equation; k = 1.38 X 10-2.1 J/K.
Breakdown voltage The reverse-biasing voltage across a diode that causes it to conduct heavily in the reverse direction (cathode to anode).
Carrier. See charge carrier.
Carrier density. The number of carriers (holes or electrons) per cubic meter of semiconductor ·material. See also electron density and hole density.
Cathode The N side of Ii PN junction diode.
Charge carrier An electron, which carries one unit of negative charge, q, or a hole, which carries one unit of positive charge
Orbit Path occupied by electrons around the nucleus of an atom.
p See hole density.
Pi Hole density of intrinsic semiconductor material.
P+ Heavily doped P material.
P material Semiconductor material that has been doped (with acceptor atoms)
so that it contains more holes than free electrons.
PN junction Boundary between adjoining regions of P and N material; forms
a diode.
Proton Atomic particles in the nucleus of an atom; has one unit of positive charge
equal in magnitude to the charge of ant’ electron (q).
q See charge o] n» ctectr
tin Samo :: -t-
IJp Posit;’ “Jdrge carried by one proton (or hole); has the same J?agnitude as q.
Recombination The occurrence of a free electron falling into a hole.
Resistivity (p) A measure’ of the ability of a particular material to create resistance;
the resistance per un!t length and cross-sectional area of th~ material; p’ = lilT.
R? •.. erse bias Connection of the positive terminal’ of a voltage source to the N
side of a PN junction and the negative terminal to the P side’ (in a diode, positive
~erminal to cathode and negative terminal to anode).
Rupture, of a covalent bond The release of an electron from the bond; creates a
free electron and a hole.
Saturation current (/.) The reverse current through a PN junction that flows when
the junction is reverse biased by a few tenths of a volt.
Schottky diode A diode formed by an MS junction consisting of aluminum and
N-type silicon.
Semiconductor A crystalline material that is neither a good conductor nor an
insulator; current flow in a semiconductor is the motion of both electrons and holes.
Shell An orbit around the nucleus of an atom; can contain a specific maximum
number of electrons. .
Si Symbol for the element silicon.
Space cbarge A layer of charged particles lying in the P .and N sides of a PN
junction.
Subshell A subdivision of a shell; can contain a speci~c maximum number of electrons.
Thermal voltage (Vr) A component of the barrier potential at a PN junction;
value depends on temperature. ‘
Vale~ce band Band of energies possesse? by valence electrons in an atom.
Valence electron An electron in the outermost shell of an atom .
Valence shell Outermost electron shell of an atom.
VnR See breakdown voltage.
V See thermal voltage.
Zener diode A diode designed to break down at a specific reverse voltage and to be used in the breakdown region .