What type of impurity is added to obtain n-type semicondutor?

Explanation

To obtain an n-type semiconductor, we need to follow these steps:

### Step-by-Step Solution:

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

**Hint**: Remember that semiconductors can be classified into two types based on the charge carriers: n-type and p-type.
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