Semiconductor Devices Flashcards

Flashcards about Semiconductor Devices and related concepts.

What are Semiconductor Devices?

Electronic components that exploit the electrical properties of semiconductor materials for rectification, amplification, switching, and optoelectronics.

What is a Zener Diode?

A special type of diode designed to operate in the reverse breakdown region, with a sharp breakdown voltage known as Zener voltage (Vz). In forward biased condition it acts like an ordinary diode

How does a Zener diode operate in reverse bias?

In reverse bias, it maintains a stable voltage after breakdown.

How does a Zener diode act as a voltage regulator?

It maintains a constant voltage across itself when operated in the reverse breakdown region, effectively regulating the output voltage to a fixed value.

What are the two ways a P-N diode can react to negative potential?

Avalanche Breakdown and Zener Breakdown

What is Avalanche Breakdown?

Occurs in the presence of a high electric field where electrons gain high kinetic energy, breaking covalent bonds and creating more electron-hole pairs, leading to a high reverse-biased current and irreversible damage.

What is Zener Breakdown?

A controlled way of creating breakdown in p-n junction diodes through heavy doping, allowing electrons to jump easily to the conduction band; a temporary effect due to the high electric field.

Briefly explain Avalanche Breakdown

Occurs in lightly doped junctions with wide depletion widths at higher reverse voltages due to thermally generated electrons gaining enough kinetic energy to produce more electrons by collision.

Briefly explain Zener Breakdown

Occurs in heavily doped junctions with narrow depletion widths due to the rupture of covalent bonds by strong electric fields set up by the reverse voltage.

What is a Tunnel Diode?

A heavily doped p-n junction diode in which the electric current decreases as the voltage increases; used as a very fast switching device, in high-frequency oscillators and amplifiers.

How does a Tunnel Diode work?

It exhibits quantum mechanical tunneling, allowing current to flow in reverse bias and enabling high-speed switching.

What does Tunneling refer to in the context of Tunnel Diodes?

Electrons pass through the energy barrier that would otherwise prevent them from flowing, due to the small barrier width resulting from heavy doping.

What is the negative resistance region in a Tunnel Diode?

The region between the peak point (Ip) and valley point (Iv) on the V-I characteristics curve, where current decreases with an increase in applied voltage.

What are some applications of Tunnel Diodes?

Switch, amplifier and oscillator

What is a Semiconductor Laser?

A specifically fabricated p-n junction diode that emits laser light when forward biased.

What is Recombination Radiation?

The emission of light radiation (photons) during the recombination process in certain direct band gap semiconductors, stimulating other electrons and holes to recombine and produce laser light.

What are some applications of Semiconductor Lasers?

Fiber optic communication, healing wounds by infrared radiation, pain relief, laser printers, CD writing and reading, laser pointers, and barcode readers.

What are Photonic Devices?

Components that deal with the generation, manipulation, and detection of light (photons), combining optics and electronics for various applications.

What are key types of Photonic Devices?

Photodetectors, Solar Cells, and Light Emitting Diodes (LEDs).

What are Photo Detectors?

Devices that convert light into an electrical signal, used at the receiving end of an optical communication link; examples include photodiodes and phototransistors.

What is the working principle of a photodetector?

When photons hit the semiconductor material, they excite electrons, creating an electron-hole pair, resulting in a photocurrent.

How does the Photo Diode work

Photon absorption leads to electron-hole pair generation in the depletion region, resulting in current flow.

What is a Junction Photo Diode?

Functions as a light-sensitive diode, where the current varies linearly with the flux of light when the reverse-biased pn junction is exposed to light.

What are the types of photodiode?

PN Photodiode, Schottky photodiode, PIN Photodiode, and Avalanche photodiode.

What are some applications of Junction Photo Diodes?

Used in photoconductors, photomultiplier tubes, charged-coupled devices, smoke detectors, compact disk players, infrared remote controls, medical equipment like CT scans, and optical communication.

What is a PIN Photodiode?

A type of photodetector with an undoped intrinsic semiconductor region between a p-type and an n-type semiconductor, enhancing light absorption and carrier contribution to the photocurrent.

What are the advantages of using PIN Photodiodes?

High Speed, Low Dark Current, and High Efficiency.

What are the applications of PIN Photodiodes?

Used in fiber optic communication, light sensors, medical equipment like CT scanners, and camera sensors.

What are Solar Cells?

Nonmechanical devices that convert sunlight directly into electricity through the photovoltaic effect.

How do Solar Cells work?

Light Absorption, Electron Excitation, Electric Current Generation, and Power Conversion.

What is value of a solar cell in terms of Output Voltage?

A single solar cell produces an output voltage of about 0.6 V

What is the efficiency of a solar cell?

The ratio of the maximum output electrical power to the input optical power.

What are some applications of Solar Cells?

Solar panels on rooftops, solar farms, portable devices, space missions, telecommunication, defense equipment, pocket calculators, watches, and radios.

What is a Light Emitting Diode (LED)?

A semiconductor device that emits light when an electric current flows through it; electrons recombine with holes, emitting light in the process.

How do LEDs work?

When forward-biased, electrons and holes recombine in the active region, emitting photons; the wavelength (colour) of emitted light depends on the semiconductor material’s bandgap energy.

What are some common applications of LEDs?

Traffic signals, indicator lamps, vehicle head lamps, domestic lighting, optical communication, aviation lighting, picture phones, digital watches, etc.

What are Semiconductor Devices?

Electronic components that exploit the electrical properties of semiconductor materials for rectification, amplification, switching, and optoelectronics.

What is a Zener Diode?

A special type of diode designed to operate in the reverse breakdown region, with a sharp breakdown voltage known as Zener voltage (Vz). In forward biased condition it acts like an ordinary diode

How does a Zener diode operate in reverse bias?

In reverse bias, it maintains a stable voltage after breakdown.

How does a Zener diode act as a voltage regulator?

It maintains a constant voltage across itself when operated in the reverse breakdown region, effectively regulating the output voltage to a fixed value.

What are the two ways a P-N diode can react to negative potential?

Avalanche Breakdown and Zener Breakdown

What is Avalanche Breakdown?

Occurs in the presence of a high electric field where electrons gain high kinetic energy, breaking covalent bonds and creating more electron-hole pairs, leading to a high reverse-biased current and irreversible damage.

What is Zener Breakdown?

A controlled way of creating breakdown in p-n junction diodes through heavy doping, allowing electrons to jump easily to the conduction band; a temporary effect due to the high electric field.

Briefly explain Avalanche Breakdown

Occurs in lightly doped junctions with wide depletion widths at higher reverse voltages due to thermally generated electrons gaining enough kinetic energy to produce more electrons by collision.

Briefly explain Zener Breakdown

Occurs in heavily doped junctions with narrow depletion widths due to the rupture of covalent bonds by strong electric fields set up by the reverse voltage.

What is a Tunnel Diode?

A heavily doped p-n junction diode in which the electric current decreases as the voltage increases; used as a very fast switching device, in high-frequency oscillators and amplifiers.

How does a Tunnel Diode work?

It exhibits quantum mechanical tunneling, allowing current to flow in reverse bias and enabling high-speed switching.

What does Tunneling refer to in the context of Tunnel Diodes?

Electrons pass through the energy barrier that would otherwise prevent them from flowing, due to the small barrier width resulting from heavy doping.

What is the negative resistance region in a Tunnel Diode?

The region between the peak point (Ip) and valley point (Iv) on the V-I characteristics curve, where current decreases with an increase in applied voltage.

What are some applications of Tunnel Diodes?

Switch, amplifier and oscillator

What is a Semiconductor Laser?

A specifically fabricated p-n junction diode that emits laser light when forward biased.

What is Recombination Radiation?

The emission of light radiation (photons) during the recombination process in certain direct band gap semiconductors, stimulating other electrons and holes to recombine and produce laser light.

What are some applications of Semiconductor Lasers?

Fiber optic communication, healing wounds by infrared radiation, pain relief, laser printers, CD writing and reading, laser pointers, and barcode readers.

What are Photonic Devices?

Components that deal with the generation, manipulation, and detection of light (photons), combining optics and electronics for various applications.

What are key types of Photonic Devices?

Photodetectors, Solar Cells, and Light Emitting Diodes (LEDs).

What are Photo Detectors?

Devices that convert light into an electrical signal, used at the receiving end of an optical communication link; examples include photodiodes and phototransistors.

What is the working principle of a photodetector?

When photons hit the semiconductor material, they excite electrons, creating an electron-hole pair, resulting in a photocurrent.

How does the Photo Diode work

Photon absorption leads to electron-hole pair generation in the depletion region, resulting in current flow.

What is a Junction Photo Diode?

Functions as a light-sensitive diode, where the current varies linearly with the flux of light when the reverse-biased pn junction is exposed to light.

What are the types of photodiode?

PN Photodiode, Schottky photodiode, PIN Photodiode, and Avalanche photodiode.

What are some applications of Junction Photo Diodes?

Used in photoconductors, photomultiplier tubes, charged-coupled devices, smoke detectors, compact disk players, infrared remote controls, medical equipment like CT scans, and optical communication.

What is a PIN Photodiode?

A type of photodetector with an undoped intrinsic semiconductor region between a p-type and an n-type semiconductor, enhancing light absorption and carrier contribution to the photocurrent.

What are the advantages of using PIN Photodiodes?

High Speed, Low Dark Current, and High Efficiency.

What are the applications of PIN Photodiodes?

Used in fiber optic communication, light sensors, medical equipment like CT scanners, and camera sensors.

What are Solar Cells?

Nonmechanical devices that convert sunlight directly into electricity through the photovoltaic effect.

How do Solar Cells work?

Light Absorption, Electron Excitation, Electric Current Generation, and Power Conversion.

What is value of a solar cell in terms of Output Voltage?

A single solar cell produces an output voltage of about 0.6 V

What is the efficiency of a solar cell?

The ratio of the maximum output electrical power to the input optical power.

What are some applications of Solar Cells?

Solar panels on rooftops, solar farms, portable devices, space missions, telecommunication, defense equipment, pocket calculators, watches, and radios.

What is a Light Emitting Diode (LED)?

A semiconductor device that emits light when an electric current flows through it; electrons recombine with holes, emitting light in the process.

How do LEDs work?

When forward-biased, electrons and holes recombine in the active region, emitting photons; the wavelength (colour) of emitted light depends on the semiconductor material’s bandgap energy.

What are some common applications of LEDs?

Traffic signals, indicator lamps, vehicle head lamps, domestic lighting, optical communication, aviation lighting, picture phones, digital watches, etc.

What is Electroluminescence?

The process of converting electrical energy into light. LEDs are a practical example of this principle.

What is Luminous Intensity?

The amount of light emitted per unit solid angle, measured in candelas (cd).

What is Luminous Flux?

The total luminous flux emitted by a light source, measured in lumens (lm).