Consider n-type gallium arsenide doped with Nd = 1016/cm3. Assume that 1014 /cm3 electron hole pairs have been generated at t = 0. Assume that minority carrier life time is 10 ns. Assuming no carrier generation for t > 0, excess electron concentration at t = 10 ns is
1
1014/cm3
2
3.68 × 1013 /cm3
3
1016/cm3
4
3.68 × 1015/cm3