Black's equation

Black's Equation is a mathematical model for the mean time to failure (MTTF) of a semiconductor circuit due to electromigration: a phenomenon of molecular rearrangement (movement) in the solid phase caused by an electromagnetic field.

The equation is:

${\displaystyle MTTF={\frac {A}{j^{n}}}e^{\left({\frac {Q}{kT}}\right)}}$

${\displaystyle A}$ is a constant
${\displaystyle j}$ is the current density
${\displaystyle n}$ is a model parameter
${\displaystyle Q}$ is the activation energy
${\displaystyle k}$ is Boltzmann's constant
${\displaystyle T}$ is the absolute temperature in K

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