Physical Quantities

Symbol

Unit

Description










a

1

Kinetic exponent in the RD model
Aab

- 1
s

Electronic matrix element in the Franck-Condon approximation
Ap

V

Prefactor of the permanent component in the NBTI fit formula
Ar

V

Prefactor of the recoverable component in the NBTI fit formula
Ayz

m2

Interface area in the yz-plane
B

1

Parameter in the empirical relation of the universal recovery
cn

 3 -1
m s

Electron capture coefficient
c
 p

m3s-1

Hole capture coefficient
cNMP
 p

m3s-1

Hole capture coefficient in the NMP model
cNMP
 p,0

m3s-1

Temperature independent prefactor of cNMP
 p
C
  ox

CV- 1m-2

Areal gate capacitance
Dc

m2s-1

Diffusion coefficient in the RDD model
Dc1D

J-1

Density of states of a one-dimensional, confined electron gas
Dc3D

m-2J-2

Density of states of a three-dimensional, confined electron gas
Dit

 -2 -1
m  J

Interface trap density of states
Dn

 -3 -1
m  J

Electron density of states in the conduction band
D
  n,1D

m-1J-1

Density of states of a one-dimensional electron gas
Dn,1D+2D

m-3J-2

Product of Dn,1D  and Dn,2D
Dn,2D

m-2J-1

Density of states of a two-dimensional electron gas
Dox

m-2J-1

Oxide trap density of states
Dp

m-3J-1

Hole density of state in the valence band
Dp,c3D

m-2J-2

Density of states of a three-dimensional, confined hole gas
Dp,1D

m-1J-1

Density of states of a one-dimensional hole gas
Dp,1D+2D

 -3 -2
m  J

Product of Dp,1D  and Dp,2D
Dp,2D

 -2 -1
m  J

Density of states of a two-dimensional hole gas
DX

 2 -1
m s

Diffusion coefficient of the species X  in the RD model
e
n

m3s-1

Electron emission coefficient
ep

m3s-1

Hole emission coefficient
eNpMP

m3s-1

Hole emission coefficient in the NMP model
eNpM,0P

m3s-1

Temperature independent prefactor of eNnMP
E

J

Electron energy in the band edge energy diagram
Eact

J

Activation energy
Eb

J

Electron energy in the conduction/valance band
E
  c

J

Conduction band edge energy
EDcFT

J

Conduction band edge energy in DFT calculations
Ec,0

J

Conduction band edge energy in the flat band case
Ed

J

Demarcation energy
Eds

J

Dissociation barrier in the reaction-limited model
Edsm

J

Mean value of the dissociation barriers in the reaction-limited model
Ef

J

Fermi energy
Ei

J

Energy of the electron system in the state i
E
 n,i

J

Energy of a channel electron in the quasi-bound state i
Ep,i

J

Energy of a channel hole in the quasi-bound state i
Eq1∕q2

J

Switching trap level for a transition from charge state q1  to q2
Et

J

Trap level
Et,0

J

Trap level in the flat band case
Et,1

J

Trap level of the oxygen vacancy in the TSM
E
  t,2

J

Trap level of the E′ center in the TSM
E ′t

J

Trap level in the NMP model
Etot,ij

J

Energy of the combined system of electrons and nuclei in the state ij
Ev

J

Valence band edge energy
 DFT
Ev

J

Valence band edge energy in DFT calculations
Ev,0

J

Valence band edge energy in the flat band case
Ex

J

x  -component of electron energy E
Exc

J

Exchange-correlation energy
faLbSF

1

Lineshape function
faαbβ

1

Franck-Condon factor
feq,i,n

1

Equilibrium occupancy for the trap n
f
 i

1

Occupancy of a trap in state i
fi,n

1

Occupancy for the trap n  in state i
fit

1

Interface trap occupancy
fn

1

Electron occupancy
f
 ox

1

Oxide trap occupancy
fp

1

Hole occupancy
ft

1

Trap occupancy
 eq
ft

1

Equilibrium trap occupancy
ft,2

1

Electron occupancy of the   ′
E center in the TSM
f
 FD

1

Fermi-Dirac distribution
Fox

Vm -1

Oxide field
Fc

Vm -1

Reference field for the MPFAT mechanism
Fox,r

Vm -1

Oxide field during relaxation
Fox,s

Vm -1

Oxide field during stress
F

1

Trap occupancy for a set of states
F
 i

N

Force on atom i
gH

m-3J-1

Hydrogen trap density of states in the RDD model
gν

1

Degeneracy of the valley ν
H

 -3
m

Hydrogen concentration in the RDD model
H

   -1
Am

Magnetic field strength
H

J

General hamilton operator in the derivation of Fermi’s golden rule
Hc

m-3

Free hydrogen concentration in the RDD model
Hch

J

Hamilton operator of the channel in the derivation of Fermi’s golden rule
^Htot

J

Hamilton operator of an atomic system
ID

A

Drain current
ID0

A

Initial drain current
k

m-1

Electron wavevector
k

1

Coupling constant between τcap  and τem  in Yang’s model
kf

- 1
s

Forward rate of a reaction/transition
kf,0

- 1
s

Attempt frequency in the reaction-limited model
k
 r

s- 1

Reverse rate of a reaction/transition
kx∕y∕z

m-1

x∕y∕z  -component of the electron wavevector
Lx

m

Length of the substrate in the x  -direction
mn

m

Effective mass of the electrons
mn,ν

m

Effective mass of the electrons for the valley index ν
m
  p

m

Effective mass of the holes
mp,ν

m

Effective mass of the holes for the valley index ν
mt

m

Tunneling mass of the charge carriers
M

kg

Oscillator mass in the harmonic approximation
Ma αbβ

J

Matrix element for a vibronic transition from state aα  to state bβ
M
  if

J

Matrix element for a transition from state i  to state f
n

m-3

Electron density
np

1

Power law exponent of permanent component in the NBTI fit formula
nr

1

Power law exponent of recoverable component in the NBTI fit formula
nRD

1

Power law exponent in the RD model
N
  a

m-3

Acceptor concentration
Nc

m-3

Effective conduction band weight
Nc,H

m-3

Effective density of conduction states in the RDD model
Nd

m-3

Donor concentration
Nit

m-2

Concentration of interface states per area
Nit,0

 -2
m

Initial concentration of interface states per area
Nox

 -2
m

Number of oxide charges per area
N
  t

m-3

Trap density
Nv

m-3

Effective valence band weight
Nx

1

Number of states for a free electrons/holes gas in the x  -direction
Nyz

1

Number of states for a free electrons/holes gas in the yz  -plane
Nxyz

1

Number of states for a free electrons/holes gas in the xyz  -volume
p

 -3
m

Hole density
pij

- 1
s

Transition probability from state i  to state j
q

m

Configuration coordinate
qi

m

Configuration coordinate at the energy minimum i
Qit

Cm -2

Areal interface charges
Qox

   -2
Cm

Areal oxide charges
raαbβ

- 1
s

Vibronic transition rate from state aα  to state bβ
rcap,e

- 1
s

Electron capture rate
r
 cap,h

s- 1

Hole capture rate
re

s- 1

Electron tunneling rate
req,ij,n

s- 1

Transition rate rij  of a trap n  during equilibrium conditions
re,q1∕q2

s- 1

Electron tunneling rate from the charge state q1  to q2  in the LSM
rem,e

s- 1

Electron emission rate
rem,h

s- 1

Hole emission rate
rij

s- 1

Rate for the transition Ti→j
rh

s- 1

Hole tunneling rate
rh,q1∕q2

- 1
s

Hole tunneling rate from the charge state q1  to q2  in the LSM
Ri

1

Ratio of the vibration frequencies in an NMP transition
ri

m

Spatial coordinates of electron i
R

s- 1

Transition rate matrix
Ri

m

Spatial coordinates of atom i
s

 -1  -1
K  V   m

Scaling factor for stress/relaxation curves
s

K-1V -1m

Scaling factor s  during relaxation

Scaling factor   during stress

Prefactor of the scaling factor

Action in the WKB method

Huang-Rhys factor for an NMP transition

Time

Thickness of the insulator

Relaxation time

Stress time

First measurement point during stress

Temperature

Transmission coefficient for tunneling through the conduction band

Transmission coefficient for tunneling through the valence band

Temperature during equilibrium conditions

Transition from state   to state

Transitions between the states   to state

Chain of the transitions   and

Temperature during relaxation

Temperature during stress

Electron kinetic energy operator

Nucleus kinetic energy operator

Adiabatic potential of an atomic system

  for charge state

  in the minimum configuration of state

Effective electron potential

Thermal velocity of the electrons

Thermal velocity of the holes

Velocity of atom

Defect potential

Channel potential in the derivation of Fermi’s golden rule

Gate bias during equilibrium conditions

Interatomic empirical potential

Gate bias

Energy of the system in state   in the TWM and the CDW

Initial energy of the system in state   in the TWM

Gate bias during relaxation

Gate bias during stress

Threshold voltage

Initial threshold voltage

Threshold voltage extracted from OTF measurements

Initial threshold voltage extracted from OTF measurements

Trap potential in the derivation of Fermi’s golden rule

Operator for the electron-nucleus Coulomb interactions

Operator for the electron-electron Coulomb interactions

Operator for the nucleus-nucleus Coulomb interactions

WKB factor for tunneling through the conduction band

WKB factor for tunneling through the valence band

Direction perpendicular to the substrate-insulator interface

Position of the substrate-insulator interface

Characteristic tunneling length for electrons

Characteristic tunneling length for holes

Position of the trap

Position of the tunneling hole front

Density of the diffusing species   in the RD model

Direction parallel to the substrate-insulator interface

Direction parallel to the substrate-insulator interface

Charge state of the diffusing species   in the RD model

Charge state of the diffusing species in the RDD model

Characteristic exponent in the reaction-limited model

Parameter in the empirical relation of the universal recovery

Field dependence factor of the thermal barrier in the TSM

Stress parameter in the TWM

Stress parameter in the CDW model

Time step in molecular dynamics

Change in the interface trap density of states

Change in the trap occupancy in state

Change in the oxide trap occupancy

Change in the trap occupancy

Energy barrier for charge trapping in the model of Kirton and Uren

Energy barrier for hole capture of the oxygen vacancy in the TSM

Energy barrier for hole capture of the  center in the TSM

Relaxation barrier to the oxygen vacancy in the TSM

Thermal barrier for the hydrogen transition in the TSM

  referenced to the substrate valence bandedge

  referenced to the substrate valence bandedge

Change in the number of interface charges per area

Change in the number of oxide charges per area

Change in the areal interface charges

Change in the areal oxide charges

Change in the threshold voltage

Change in the threshold voltage during relax

Change in the threshold voltage during stress

Change in threshold voltage extracted from OTF measurements

NMP barrier for the transition

Electric permittivity

Energy level of the bound state

Kohn-Sham eigenvalue

Energy barrier for the transition   in the NMP model

Thermodynamic trap level for a transition from charge state   to

Energy difference between the state   and  in the NMP model

Square root of the WKB factor

Mean value of the distribution of   in Yang’s model

Mobility in the RD model

Mobility of the diffusing species   in the RDD model

Valley index

Attempt frequency

Normalized relaxation time

Occupation probability for being in state

Occupation probability for set of states

Equilibrium occupation probability for set of states

Charge density

Density of traps

Trapped hydrogen density in the RDD model

Ground state charge density

Spread of the distribution of   in Yang’s model

Spread of dissociation barrier in the reaction-limited model

Cross section for an electon transition in the TSM model

Cross section for an electron tunneling in the ETM

Temperature-independent prefactor of

Cross section for a hole transition in the SRH model

Cross section for a hole transition in the eNMP model

Cross section for a hole transition in the TSM model

Cross section for hole tunneling in the ETM

Temperature-independent prefactor of

Temperature-independent prefactor of

Temperature-independent prefactor of

Transition time constant in the reaction-limited and the Yang model

Hole capture time constant over the state  in the eNMP model

Hole capture time constant over the state  in the eNMP model

Capture time constant

Electron capture time constant

Hole capture time constant

Minimal   in the eNMP model

Minimal   in the eNMP model

Emission time constant

Hole emission time constant over the state  in the eNMP model

Hole emission time constant over the state  in the eNMP model

Electron emission time constant

Hole emission time constant

Minimal   in the eNMP model

Minimal   in the eNMP model

Electron capture time constant as defined in the TSM model

Hole capture time constant as defined in the ETM

Hole capture time constant as defined in the eNMP model

Hole capture time constant as defined in the SRH model

Hole capture time constant as defined in the TSM model

Reduced electron capture time in the ETM

Reduced hole capture time in the ETM

Wavefunction of the combined system of   electrons and   nuclei

Electric potential

Surface potential

Potential energy of electrons/holes

Left/Right border of the tunnel barrier

Wavefunction of an   nuclei system in state

Single-electron wavefunction in state

Kohn-Sham orbitals

Electron channel wavefunction of the quasi-bound state

Hole channel wavefunction of the quasi-bound state

Wavefunction of an   electron system in state

Wavefunction of an   electron system in the ground state

Oscillator frequency in the harmonic approximation