Fundamentals of Semiconductor Physics

What is a semiconductor?

• A semiconductor is a material that can conduct electricity under certain conditions, used in electronic devices.

• A semiconductor is a device that stores electrical energy.

• A semiconductor is a non-conductive material used for insulation.

• A semiconductor is a type of metal that always conducts electricity.

Explain the difference between intrinsic and extrinsic semiconductors.

• Intrinsic semiconductors are always doped with impurities.

• Intrinsic semiconductors are pure materials, while extrinsic semiconductors are doped with impurities to enhance conductivity.

• Extrinsic semiconductors are pure materials with no impurities.

• Intrinsic semiconductors have lower conductivity than extrinsic semiconductors.

What role do dopants play in semiconductor materials?

• Dopants reduce the thermal conductivity of semiconductor materials.

• Dopants create a vacuum in semiconductor materials.

• Dopants enhance the electrical conductivity of semiconductor materials by introducing charge carriers.

• Dopants are used to insulate semiconductor materials.

Define the term 'band gap' in semiconductors.

• The band gap is the amount of current flowing through a semiconductor.

• The band gap is the temperature at which a semiconductor operates.

• The band gap is the physical size of a semiconductor material.

• The band gap is the energy difference between the valence band and the conduction band in semiconductors.

What is the significance of the Fermi level in semiconductors?

• The Fermi level determines the color of a semiconductor.

• The Fermi level is irrelevant to the conductivity of semiconductors.

• The Fermi level only applies to metals, not semiconductors.

• The Fermi level indicates the energy state of electrons in a semiconductor, influencing its electrical properties and behavior.

Describe how temperature affects the conductivity of semiconductors.

• Temperature increases conductivity in semiconductors due to more electrons being excited to the conduction band.

• Conductivity in semiconductors is only affected by impurities, not temperature.

• Temperature has no effect on the conductivity of semiconductors.

• Higher temperatures decrease conductivity by reducing electron mobility.

What are p-type and n-type semiconductors?

• P-type semiconductors have negative charge carriers (holes)

• Both P-type and N-type semiconductors have neutral charge carriers

• P-type semiconductors have positive charge carriers (holes), while N-type semiconductors have negative charge carriers (electrons).

• N-type semiconductors have positive charge carriers (electrons)

Explain the concept of charge carriers in semiconductors.

• Charge carriers are exclusively positive ions.

• Charge carriers are only protons in semiconductors.

• Charge carriers do not exist in semiconductors.

• Charge carriers in semiconductors are electrons and holes, with electrons being negative carriers and holes acting as positive carriers.

What is the purpose of a diode in semiconductor applications?

• The purpose of a diode in semiconductor applications is to control the direction of current flow.

• To store electrical energy.

• To amplify electrical signals.

• To convert AC to DC power.

How do transistors function as switches in electronic circuits?

• Transistors generate power by converting heat into electricity.

• Transistors store data by holding charge in a capacitor.

• Transistors act as switches by controlling current flow based on base voltage.

• Transistors amplify signals by increasing voltage levels.