Review Questions

Final Exam Tuesday Dec. 16, 1997

1. Neamen 7.6 (N_a/N_d = 0.083)
2. Neamen 7.9 (b) J_p = 0.6 A/cm², c) J_n = 1.39 A/cm²)
3. Neamen 7.11 (E_g = 0.77 eV)
4. Consider the calculation of the current in a p-n diode. How do you justify that the electron and hole current density is constant as indicated in Fig. 7.8 (Neamen). What physical mechanism is ignored and why?
5. Neamen 9.2
6. Neamen 9.10 (x_B = 0.994 micron)
7. Consider the transistor of problem 9.10. Calculate the minority carrier lifetime in the base for which the base transport factor equals the emitter efficiency.
8. Explain why a bipolar transistor has current gain.