Semiconductor Devices

Study Notes

Semiconductor devices are the building blocks of modern electronics
They operate by manipulating the flow of electrical current using semiconductor materials
Semiconductor materials have electrical conductivity between that of conductors and insulators

Diodes: allow current to flow in one direction, used for rectification and switching
Transistors: amplify or switch electronic signals, used for amplification and switching
Thyristors: control the flow of current, used for power control and switching

Intrinsic semiconductor: pure semiconductor material with no impurities
Extrinsic semiconductor: semiconductor material with intentionally added impurities (dopants)
- N-type: doped with donor impurities, creates excess electrons
- P-type: doped with acceptor impurities, creates excess holes

PN junction: interface between P-type and N-type semiconductor materials
Depletion region: region around the PN junction where charge carriers are depleted
Barrier potential: voltage required to overcome the depletion region
Forward bias: applying a positive voltage to the P-side and a negative voltage to the N-side, reduces the barrier potential
Reverse bias: applying a positive voltage to the N-side and a negative voltage to the P-side, increases the barrier potential

Forward bias: diode conducts current, acts as a closed switch
Reverse bias: diode does not conduct current, acts as an open switch
Breakdown voltage: voltage at which the diode begins to conduct current in reverse bias

Bipolar Junction Transistor (BJT): uses both positive and negative charge carriers
Field-Effect Transistor (FET): uses voltage to control the flow of current
Modes of operation:
- Cut-off: transistor does not conduct current
- Saturation: transistor conducts maximum current
- Active: transistor operates in the linear region, amplifying the input signal

Semiconductor devices are the building blocks of modern electronics, operating by manipulating the flow of electrical current using semiconductor materials.
Semiconductor materials have electrical conductivity between that of conductors and insulators.

Diodes: allow current to flow in one direction, used for rectification and switching.
Transistors: amplify or switch electronic signals, used for amplification and switching.
Thyristors: control the flow of current, used for power control and switching.

Intrinsic semiconductor: pure semiconductor material with no impurities.
Extrinsic semiconductor: semiconductor material with intentionally added impurities (dopants).
N-type: doped with donor impurities, creates excess electrons.
P-type: doped with acceptor impurities, creates excess holes.

PN junction: interface between P-type and N-type semiconductor materials.
Depletion region: region around the PN junction where charge carriers are depleted.
Barrier potential: voltage required to overcome the depletion region.

Forward bias: diode conducts current, acts as a closed switch.
Reverse bias: diode does not conduct current, acts as an open switch.
Breakdown voltage: voltage at which the diode begins to conduct current in reverse bias.

Bipolar Junction Transistor (BJT): uses both positive and negative charge carriers.
Field-Effect Transistor (FET): uses voltage to control the flow of current.
Modes of operation:
- Cut-off: transistor does not conduct current.
- Saturation: transistor conducts maximum current.
- Active: transistor operates in the linear region, amplifying the input signal.