Multiphonon thermal-field ionization of deep centers in semiconductors

The problem of thermal-field ionization of deep impurity centers in semiconductors is studied. It is shown that \(W_{ion} = W_0 e^{\alpha F^2 }\) , where F is the electric field strength. Also, the lifetime for multiphonon nonradiative capture is calculated as a function of F. It is shown that the relative change in lifetime is $$\frac{{\Delta \tau }}{{\tau ^0 }} = \frac{{\tau ---\tau _0 }}{{\tau _0 }} \approx - \alpha F^2 .$$