Simple analytical expressions for the fringing field and fringing-field-induced transfer time in charge-coupled devices

The author presents simple analytical solutions for the potential and the fringing field, especially for charge-coupled devices (CCDs). A description of the influence of the insulation layer in terms of an equivalent substrate thickness is used to find expressions for the optimal charge transport depth and charge transfer time for small charge packets in CCDs. The thickness of the insulation layer is accounted for by a scaling rule that is a nonlinear function of the thickness and dielectric constant of the insulation layer and the lateral dimensions of the device. Compared with computer simulations this technique gives good results for surface potentials that are found in CCDs. The results are used to calculate the optimal transfer depth and minimal transfer time in bulk and surface CCDs.<
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