1. What is Semiconductor Carrier Concentration?

The carrier concentration in semiconductors refers to the number of charge carriers (electrons and holes) per unit volume. In intrinsic (pure) semiconductors, the electron and hole concentrations are equal. In extrinsic (doped) semiconductors, the law of mass action relates these concentrations.

2. How Does the Calculator Work?

The calculator uses the mass action law equation:

Where:

• \( p \) — Hole concentration (1/m³)
• \( n_i \) — Intrinsic carrier concentration (1/m³)
• \( n \) — Electron concentration (1/m³)

Explanation: This equation maintains the product of electron and hole concentrations equal to the square of the intrinsic concentration at thermal equilibrium.

3. Importance of Carrier Concentration

Details: Carrier concentration determines the electrical conductivity of semiconductors and is crucial for designing electronic devices like diodes and transistors.

4. Using the Calculator

Tips: Enter intrinsic carrier concentration and electron concentration in 1/m³ units. Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is typical intrinsic carrier concentration for silicon at room temperature?
A: For silicon at 300K, n_i ≈ 1.5 × 10¹⁶ m^-3.

Q2: How does temperature affect intrinsic concentration?
A: n_i increases exponentially with temperature as more electron-hole pairs are thermally generated.

Q3: What is the relationship for intrinsic semiconductors?
A: In intrinsic semiconductors, n = p = n_i.

Q4: How does doping affect carrier concentrations?
A: Doping increases one type of carrier while decreasing the other to maintain n × p = n_i².

Q5: What are typical units for carrier concentration?
A: Usually expressed in cm^-3 or m^-3 (1 cm^-3 = 10⁶ m^-3).