Semiconductor of both p-type and n-type are produced by

Options

A. ionic solids
B. metallic solids
C. covalent solids
D. molecular solids

Answer

To solve the question about how semiconductors of both p-type and n-type are produced, we can break it down into a few clear steps:

### Step 1: Understanding P-type Semiconductors
- P-type semiconductors are formed by doping a pure semiconductor (like silicon) with trivalent impurities.
- Trivalent impurities have three valence electrons. Common examples include boron and gallium.

### Step 2: Doping Process for P-type
- When silicon (which has four valence electrons) is doped with a trivalent element (like boron), it forms covalent bonds with the silicon atoms.
- Each boron atom forms three bonds with silicon atoms, leaving one silicon atom with an incomplete bond, creating "holes" which act as positive charge carriers.

### Step 3: Understanding N-type Semiconductors
- N-type semiconductors are created by doping a pure semiconductor with pentavalent impurities.
- Pentavalent impurities have five valence electrons. A common example is phosphorus.

### Step 4: Doping Process for N-type
- When silicon is doped with a pentavalent element (like phosphorus), the phosphorus atom forms covalent bonds with silicon atoms.
- The extra electron from phosphorus (the fifth electron) becomes a free charge carrier, contributing to negative charge carriers in the semiconductor.

### Step 5: Conclusion
- Both p-type and n-type semiconductors are formed through the process of doping, resulting in covalent solids.
- The final answer to the question is that semiconductors of both p-type and n-type are produced by covalent solids.

### Final Answer:
Semiconductors of both p-type and n-type are produced by covalent solids.

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