Solutions to Homework # 3

(02/02/2004 – 02/13/04)

3.1 N_A = 10¹⁸ / cm³ N_D = 10¹⁵ / cm³

p_p = N_A = 10¹⁸ / cm³

n_n = N_D = 10¹⁵ / cm³

Using p_p * n_p = p_n * n_n = n_i² = 10²⁰ / cm⁶ at 300 K, we get

n_p = 10² / cm³

n_n = 10⁵ / cm³

[ V_T = 25 mV at 300 K ]

W_DO = 0.984 * 10^-6 m = 0.984 m

3.2 N_A = 10¹⁹ / cm³ N_D = 10¹⁸ / cm³

W_DO = 0.0373 * 10^-6 m = 0.0373 m

X_N = 0.0339 m

X_P = 0.0034 m

E_MAX = 5.24 * 10⁵ V/cm

3.6

For Second Case, V_R = 5V

3.24

For second case,