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 𝜏𝑛0 =5 × 10−7𝑠 , and assume mobility values of 𝜇𝑛 = 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=∞?
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