Review of analytical models for the study of highly doped regions of silicon devices

Several analytical models developed to study the transport of minority carriers in heavily doped emitter regions of silicon devices are reviewed and compared. To calculate the emitter recombination current, special emphasis is placed on the models of J. Del Alamo and R.M. Swanson (ibid, vol.31, no.12, p.1878-88, 1984) and of J.S. Park, A. Neugroschel, and F. Lindholm (ibid, vol.33, no.2, p.240-8, 1986), which are shown to contain other previous models. For solar cells and photodiodes, the quantum collection efficiency and the photogenerated current are also to be calculated; the models developed by M.A. Green and A.W. Blakers (ibid, vol.30, no.10, p.1360-5, 1983) and by J. Del Alamo and Swanson (Proc. 17th IEEE Photovoltai Specialists Conf., p.1303-8, 1984) for that purpose is described and extended. The approximate analytical solutions are shown to constitute upper and lower bounds on the exact solution. The accuracy and range of applicability of these bounds are discussed.>