Elements used as semiconductor are purified by

Options

A. Van Arkel method
B. Mond process
C. Distillation
D. Zone refining

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks about the method used to purify elements that are used as semiconductors.

2. **Recognize the Elements**: The primary elements that are used as semiconductors are silicon (Si) and germanium (Ge).

3. **Determine the Purification Method**: The purification method commonly used for silicon and germanium is known as the **zone refining process**.

4. **Understand the Zone Refining Process**:
- **Setup**: In this process, an impure semiconductor rod is placed in a specialized apparatus.
- **Melting**: The rod is melted in a controlled manner, creating a molten zone.
- **Movement of Impurities**: As the molten zone moves along the rod, impurities (which are considered solute particles) tend to concentrate in the molten area due to their solubility in the liquid phase.
- **Separation**: The molten zone is then moved along the rod, allowing the impurities to be pushed ahead of the solidifying front. This results in the solidification of a purer semiconductor behind the molten zone.

5. **Final Result**: After several passes of the molten zone, the end of the rod contains a significantly higher purity of the semiconductor material, effectively separating the impurities from the desired element.

6. **Conclusion**: The correct answer to the question is that elements used as semiconductors are purified by the **zone refining process**.

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