Question

Assume that a uniform p-type region of silicon with length L-10 μm, μη-1400 cm2/V-s, and lifetime t 1 us at T 300 K is uniformly illuminated by photon flux G 1019/cm2s. Assume that that all carriers are extracted at x-L (such that Δη-0), while An-1014 /cm3 at x 0. Assume that Po An everwhere. Now consider the system after reaching a steady state. 2. Write down the simplest form of the minority carrier diffusion equation that accurately describes its behavior. Briefly justify your answer. Solve for and sketch the minority carrier concentration Δn as a function of position between x 0 andx L How would this problem change if the minority carrier lifetime τ" were reduced to 7 ns? Justify your answer quantitatively a. b. c.

Answer 1

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