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Based on the Hall-Shockley-Read formalism we have successfully demonstrated that of the surface generation of minority carriers (MC) in a semiconductor of the Si-MOS-structure, leaded in the strong in-equilibrium depletion state, is ineffective due to rapid establishment of the quasi-equilibrium between surface generation centers and MC band. At the silicon surface without deep levels MC can be appeared only due to the diffusion from the quasi-neutral region. However, this diffusion takes place only at T> 100°C. Thus, in the perfect Si-MOS-structure at room temperature the state of non-equilibrium depletion can be conserved the infinitely long time, as a MC thermodiffusion from a Si electroneutral volume at the T<100°C is ineffective. In this situation single source of the MC generation is the edge effect. This effect can be artificially enhanced by staggered inhomogeneity gate oxide. Then, in depletion layer under the (thick) oxide the quasi-equilibrium between surface generation centers and MC band will be not established due to continuous MC leakage in the more deep potential well under (thin) oxide. The MC leakage is continued until homogenezation of a semiconductor surface. Next, a MC generation velocity will be determined the edge effect only. Experimental time dependences of the generation current Ig(t) are found to be in accordance with these concepts. On dependences Ig(t) are observed two discrete current steps. The height of steps undepends from depletion voltage Vg and their durability increase with growth of Vg. The MC generation rate and surface recombination velocity were obtained by Ig(t) curves. Increasing of grading of a gate oxide thickness allow to rise a number of steps on the Ig(t) dependence. The edge effect in a MIS-structure easily is increased of external stresses that it is allowed to use the edge effect for the creation sensor-devices of a new type.
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