512 APPENDIX A. ALIST OF SYMBOLS
EFn electron quasi-Fermi level
EFp hole quasi-Fermi level
Ee(Eh) energy of an electron (hole) in an optical absorption or emission measured
from the bandedges
Ec(Ev) conduction (valence) bandedge
f(E) occupation probability of an electron state with energyEat equilibrium.
This is the Fermi-Dirac function
fe(E) occupation function for an electron in non-equilibrium state. This is the
quasi-Fermi function
fh(E) occupation function for a hole = 1 −fe(E)
fτ cutoff frequency for unit current gain
fmax available power gain is unity at this frequency
E electric field
Fext external force such as an electric or magnetic force
gm transconductance of a transistor
gD output conductance of a transistor
GL electron-hole generation rate due to a light beam
Planck’s constant divided by 2π
h channel thickness of a JFET or an MESFET
h(x) depletion region thickness in an FET at positionxalong the source to drain
channel
H magnetic field
Iph photon particle current
IE,IB,IC emitter, base, and collector current in a BJT
IEn,IEp electron, hole part of the emitter current in annpnBJT
ID drain current in an FET
Io reverse bias saturation current in ap-ndiode
Is reverse bias saturation current in a Schottky diode
IGR generation recombination current in a diode
IGRo prefactor for the generation recombination current