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Next: 3.3.3 The Insulator-Metal Interface Up: 3.3 Boundary and Interface Previous: Thermionic Field Emission

3.3.2 Semiconductor-Insulator Interfaces

The condition for the semiconductor-insulator interface equivalently is determined by a continuous potential and by an applied surface charge density $ \sigma_{surf}$ according to the Gauß law:

    $\displaystyle \varphi_{semi} = \varphi_{ins}$ (3.95)
    $\displaystyle {\bf n}\cdot \varepsilon_{semi}\cdot {\bf E}_s - {\bf n}\cdot \varepsilon_{ins} \cdot {\bf E}_{ins} = \sigma_{surf}$ (3.96)

The carrier flux and the carrier energy flux are zero. The lattice temperature $ {\it T}_\mathrm{L}$ is continuous. To describe the Fermi level pinning at the surface due to a high density of states for traps, distributed surfaces charges are introduced which describe the surface depletion due to the band bending. The current densities $ \mathbf{n}\cdot\mathbf{J}$ and the energy fluxes $ \mathbf{n}\cdot\mathbf{S}$ are set to zero.