To get n-type semicoductor from silicon, it should be doped with a substance with group no.……

Options

A. 12
B. 15
C. 13
D. 15

Answer

To determine the group number of the substance that should be used to dope silicon in order to create an n-type semiconductor, follow these steps:

### Step-by-Step Solution:

1. **Understanding Semiconductors**:
- Semiconductors are materials that have electrical conductivity between that of conductors and insulators. They can be modified by adding impurities, a process known as doping.

2. **Types of Doping**:
- There are two types of doping: n-type and p-type.
- n-type doping introduces extra electrons into the semiconductor, while p-type doping creates "holes" (positive charge carriers).

3. **Identifying n-type Doping**:
- To create an n-type semiconductor from silicon (which is a group 14 element), we need to add an element that has more valence electrons than silicon.

4. **Valence Electrons of Silicon**:
- Silicon has 4 valence electrons (as it is in group 14). To create an n-type semiconductor, we need to introduce extra electrons.

5. **Choosing the Right Dopant**:
- Elements from group 15 of the periodic table have 5 valence electrons. When these elements are added to silicon, they provide an extra electron, which contributes to the n-type conductivity.

6. **Examples of Group 15 Elements**:
- Common group 15 elements used for doping silicon include phosphorus (P), arsenic (As), and antimony (Sb).

7. **Conclusion**:
- Therefore, to get an n-type semiconductor from silicon, it should be doped with a substance from group number 15.

### Final Answer:
To get an n-type semiconductor from silicon, it should be doped with a substance from group number **15**.

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