Daily review: Photodiode Quiz Practice Quiz | Daily…

Q: In which bias condition is a photodiode typically operated for high-speed applications?

Reverse bias — Reverse bias increases the depletion region width, reducing junction capacitance and enabling faster response times.

Q: What is the primary function of a photodiode?

To convert light energy into electrical current — Photodiodes are semiconductor devices that generate a current when exposed to light.

Q: What happens to the reverse leakage current of a photodiode when light intensity increases?

It increases — Light creates electron-hole pairs in the depletion region, increasing the reverse saturation current proportionally.

Q: Which material is most commonly used for photodiodes operating in the visible and near-infrared range?

Silicon (Si) — Silicon is the standard semiconductor material for photodiodes due to its bandgap and compatibility with standard fabrication.

Q: What is the significance of the 'dark current' in a photodiode?

The current that flows when no light is present — Dark current is the small leakage current that flows through the photodiode even in total darkness.

Q: What is the primary advantage of a PIN photodiode over a standard PN junction photodiode?

It has a wider depletion region for better efficiency and speed — The intrinsic (I) layer increases the depletion region width, lowering capacitance and improving sensitivity.

Q: Which parameter measures the ratio of the output current to the incident optical power?

Responsivity — Responsivity is defined as the ratio of generated photocurrent to incident light power, measured in A/W.

Q: What is 'Quantum Efficiency' in the context of a photodiode?

The number of electrons generated per incident photon — Quantum efficiency is the ratio of the number of charge carriers generated to the number of incident photons.

Q: What occurs when the photon energy incident on the photodiode is less than the semiconductor's bandgap energy?

No electron-hole pairs are generated — Photons must have energy greater than or equal to the bandgap to excite electrons from the valence to conduction band.

Q: Which type of photodiode utilizes an internal gain mechanism to improve sensitivity to low light levels?

Avalanche Photodiode (APD) — APDs operate at high reverse bias, causing impact ionization that multiplies the current carriers.

Question 1 of 10

In which bias condition is a photodiode typically operated for high-speed applications?

Reverse bias increases the depletion region width, reducing junction capacitance and enabling faster response times.

Question 2 of 10

What is the primary function of a photodiode?

Photodiodes are semiconductor devices that generate a current when exposed to light.

Question 3 of 10

What happens to the reverse leakage current of a photodiode when light intensity increases?

Light creates electron-hole pairs in the depletion region, increasing the reverse saturation current proportionally.

Question 4 of 10

Which material is most commonly used for photodiodes operating in the visible and near-infrared range?

Silicon is the standard semiconductor material for photodiodes due to its bandgap and compatibility with standard fabrication.

Question 5 of 10

What is the significance of the 'dark current' in a photodiode?

Dark current is the small leakage current that flows through the photodiode even in total darkness.

Question 6 of 10

What is the primary advantage of a PIN photodiode over a standard PN junction photodiode?

The intrinsic (I) layer increases the depletion region width, lowering capacitance and improving sensitivity.

Question 7 of 10

Which parameter measures the ratio of the output current to the incident optical power?

Responsivity is defined as the ratio of generated photocurrent to incident light power, measured in A/W.

Question 8 of 10

What is 'Quantum Efficiency' in the context of a photodiode?

Quantum efficiency is the ratio of the number of charge carriers generated to the number of incident photons.

Question 9 of 10

What occurs when the photon energy incident on the photodiode is less than the semiconductor's bandgap energy?

Photons must have energy greater than or equal to the bandgap to excite electrons from the valence to conduction band.

Question 10 of 10

Which type of photodiode utilizes an internal gain mechanism to improve sensitivity to low light levels?

APDs operate at high reverse bias, causing impact ionization that multiplies the current carriers.

Daily review: Photodiode Quiz