EE 305 Semiconductor Devices Assignment

American University of Middle East
Class Assignment W8 

Question 1 [10%]

Consider a silicon semiconductor at room temperature (𝑇 = 300 𝐾). Given that:

𝑁_𝐷 = 3 × 10¹⁷ cm⁻³ and 𝑁_𝐴 = 2 × 10¹⁴ cm⁻³

1. [1%] Determine whether this semiconductor is n-type, or p-type.
2. [2%] Draw a detailed energy band diagram for this semiconductor with showing the following:
   • 𝐸_𝐶,𝑗𝑢𝑠𝑡 𝑙𝑜𝑐𝑎𝑡𝑖𝑜𝑛
   • 𝐸_𝑉,𝑗𝑢𝑠𝑡 𝑙𝑜𝑐𝑎𝑡𝑖𝑜𝑛
   • 𝐸_𝑔, 𝑠ℎ𝑜𝑤 𝑖𝑡𝑠 𝑣𝑎𝑙𝑢𝑒
   • 𝐸_𝑖
   • 𝐸_𝐹
3. [1%] Calculate the total number of free electrons?
4. [1%] Calculate the total number of holes?
5. [1%] which carriers are considered as majority carriers and which carriers are considered as minority carriers?
6. [1%] Calculate 𝐸_𝐹 − 𝐸_𝐶 𝑖𝑛 𝐽𝑜𝑢𝑙𝑒 𝑎𝑛𝑑 𝑖𝑛 𝑒𝑉
7. [1%] Calculate 𝐸_𝐹 − 𝐸_𝑉 𝑖𝑛 𝐽𝑜𝑢𝑙𝑒 𝑎𝑛𝑑 𝑖𝑛 𝑒𝑉
8. [1%] Calculate 𝐸_𝐹 − 𝐸_𝑖 𝑖𝑛 𝐽𝑜𝑢𝑙𝑒 𝑎𝑛𝑑 𝑖𝑛 𝑒𝑉
9. [1%] if 𝑁_𝐷 = 𝑁_𝐴 = 3 × 10¹⁷ 𝑐𝑚⁻³, is this semiconductor extrinsic? Why?