The mean time to failure in semiconductors due to 
The mean time to failure in semiconductors due to this process is given by Black's equation. One-sixteenth times the electron temperature over the magnetic field in a plasma is the rate of a type of this process named for Bohm. The Prandtl number is the ratio of the rates of two different types of this process. The product of Boltzmann's constant, temperature, and the (*) mobility gives the Einstein–Smoluchowski equation for the rate of this process. The heat equation is also used to describe this process. The flux of this process equals its namesake coefficient times the negative of the concentration gradient according to Fick's law. This process operates by directed Brownian motion. This process is known as osmosis when it occurs with water. For 10 points, name this stochastic process where particles move from areas of high concentration to low concentration.
The mean time to failure in semiconductors due to this process is given by Black's equation.
diffusion [accept electromigration until “Knudsen” is read; prompt on Brownian motion] &lt;JL, Phys&gt;