Unformatted text preview: carriers are created uniformly everywhere in the sample at the rate of 4 X 10 18 cm-3 s-1 . If the lifetime of the carriers is 10-6 sec, what is the change in conductivity due to the exposure to light. Assume a steady state condition, i.e. carrier concentrations are constant in time. Use mobilities for intrinsic silicon: μ ni = 1420 cm 2 V-1 s-1 , μ pi = 500 cm 2 V-1 s-1 4. Calculate the widths of the space charge region, x n , x p , and x d in an abrupt p-n junction under thermal equilibrium conditions (T=300 K) with N A = 5 X 10 16 cm-3 and N D = 10 16 cm-3 . Take the value of the permittivity of silicon as 11.9 x 8.854 x 10-14 farads/cm....
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- Spring '07
- Electron, P-n junction, Prof. B. Jalali