[SOLVED] VE320 Homework 4

Description

1. Consider a silicon sample at 𝑇=300𝐾 that is uniformly doped with acceptor impurity atoms at a concentration of 𝑁𝑎=10¹⁶𝑐𝑚⁻³ tt 𝑡=0, a light source is turned on generating excess carriers uniformly throughout the sample at a rate of 𝑔′ =8×10²⁰𝑐𝑚⁻³𝑠⁻¹ tssume the minority carrier lifetime is 𝜏_𝑛0 =5 × 10⁻⁷𝑠 , and assume mobility values of 𝜇_𝑛 = 900𝑐𝑚²/𝑉 − 𝑠 𝑎𝑛𝑑 𝜇𝑝 = 380𝑐𝑚²/𝑉 − 𝑠  (a) Determine the conductivity of the silicon as a function of time for 𝑡≥0 (b) What is the value of conductivity at (i) 𝑡=0 and (ii) 𝑡=∞?