Chapter 29, Problem 17Q

To determine

If the atoms are donors or acceptors when a silicon semiconductor is doped with phosphorus, and the type of semiconductor formed.

Answer to Problem 17Q

Solution:

It will be donor, this will form an n- type semiconductor.

Explanation of Solution

When the silicon semiconductor is doped with phosphorus, phosphorus atoms will be donor atoms. The number of valance electron in Phosphorus is five, there will be four covalent bonds formed between phosphorus and silicon atoms and one extra electron in the phosphorus which is weakly bound to the atom and can be easily excited up to the conduction band. This process results in extra electrons in the conduction band, so silicon doped with phosphorus is an n-type semiconductor.