A pure semiconductor behaves as a good conductor at

Options

A. room temperature
B. low temperature
C. high temperture
D. Both (2) ans (3)

Answer

To determine when a pure semiconductor behaves as a good conductor, we need to analyze the properties of semiconductors at different temperatures. Here’s a step-by-step solution:

### Step 1: Understand the Structure of a Pure Semiconductor
A pure semiconductor, such as silicon, has a crystalline structure where each silicon atom forms covalent bonds with four neighboring silicon atoms. This arrangement creates a stable lattice.

**Hint:** Remember that the bonding in semiconductors is covalent and involves shared electrons.

### Step 2: Analyze the Behavior at Low Temperature
At low temperatures, the thermal energy available is insufficient to break the covalent bonds in the semiconductor. As a result, there are very few free charge carriers (electrons and holes) available for conduction.

**Hint:** Consider how temperature affects the energy of particles and their ability to overcome bonding forces.

### Step 3: Examine Room Temperature Conditions
At room temperature, the thermal energy is slightly higher, but it is still not enough to generate a significant number of free charge carriers. Therefore, the conductivity of the pure semiconductor remains low, and it does not behave like a good conductor.

**Hint:** Think about the relationship between temperature and the generation of charge carriers in semiconductors.

### Step 4: Investigate High Temperature Effects
As the temperature increases further, the thermal energy becomes sufficient to break some of the covalent bonds in the semiconductor. This process generates free electrons and holes, which are essential for electrical conduction. The increased number of charge carriers allows the semiconductor to conduct electricity more effectively.

**Hint:** Focus on the concept of thermal excitation and how it leads to the generation of charge carriers.

### Step 5: Conclusion
Thus, a pure semiconductor behaves as a good conductor primarily at high temperatures, where sufficient thermal energy is available to break the covalent bonds and generate free charge carriers.

**Hint:** Remember that the conductivity of semiconductors is heavily dependent on temperature, unlike metals which have a different behavior.

### Final Answer
A pure semiconductor behaves as a good conductor at high temperature.