Question

A uniformly doped silicon pnp transistor with base width of 2um is biased in forward active mode (with BC junction reverse biased). The doping concentrations are NE-1018cm NB-5x1016cm3, and Nc-1015cm3. Assume DB-25 cm2/s, TB-10-s and LB 16um (a) Calculate the values of no, рво, and nco. (b) For VEB 0.65V, determine the respective minority carrier concentration at the edge of the depletion layer, pa(0) and ne(0) (c) Sketch the minority carrier concentration through the device and label each curve (d) Calculate the collector current Ic. (e) Now, assume the transistor from above is biased such that both junctions are reverse biased. Note, this is "cutoff mode". Plot the minority carrier concentration in each region.

Answer 1

sol NE 2. Ne 1C AN 0-GS YER neo eve neto) 6 S 2.25 x to e。 1多 Pr A Aro -

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