Semiconductor materials like Si and Ge are usually purified by

Options

A. distillation
B. zone refining
C. liquation
D. electrolytic refining

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks how semiconductor materials like silicon (Si) and germanium (Ge) are usually purified.

2. **Identifying the Purification Method**: The common method used for purifying semiconductor materials is known as **zone refining**.

3. **Principle of Zone Refining**: Zone refining is based on the principle of **fractional distillation**. This method takes advantage of the differences in solubility of impurities in the solid and molten states of the semiconductor materials.

4. **Process of Zone Refining**:
- In zone refining, a small molten zone is moved along the length of the solid material.
- As the molten zone passes through, impurities are concentrated in the molten phase and are then moved along with the molten zone.
- This process is repeated, allowing for the effective separation of impurities from the pure semiconductor material.

5. **Final Conclusion**: Therefore, the purification of semiconductor materials like silicon and germanium is typically achieved through the method of **zone refining**.