Arsenic is used to dope germanium to obtain

Options

A. n - type semiconductor
B. p - type semiconductor
C. germanium arsenide
D. a superconducting alloy

Answer

To solve the question "Arsenic is used to dope germanium to obtain," we will follow these steps:

### Step 1: Identify the Elements
- **Arsenic (As)** is a group 15 element, which means it has 5 valence electrons.
- **Germanium (Ge)** is a group 14 element, which means it has 4 valence electrons.

### Step 2: Understand Doping
- Doping is the process of adding impurities to a semiconductor to enhance its electrical properties.
- When a group 15 element (like arsenic) is added to a group 14 semiconductor (like germanium), it introduces additional electrons into the system.

### Step 3: Analyze the Electron Contribution
- Arsenic contributes 5 valence electrons, while germanium contributes 4 valence electrons.
- When arsenic is introduced into the germanium lattice, there is one extra electron from arsenic that does not pair with any of germanium's electrons.

### Step 4: Determine the Type of Semiconductor
- The presence of this extra electron means that there are more negatively charged carriers (electrons) available for conduction.
- This results in the formation of **n-type semiconductors**, which are characterized by an abundance of electrons.

### Conclusion
- Therefore, when arsenic is used to dope germanium, it results in the formation of **n-type semiconductors**.

### Final Answer
Arsenic is used to dope germanium to obtain **n-type semiconductors**.

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