13.1.3 Understanding diodes

• A diode allows current to flow in only one direction.


  True
• The diode symbol arrow points in the direction of conventional current flow when forward biased.


  True
• What type of impurity is added to form a p-type semiconductor?

  Acceptor impurities
• What opposes the flow of current in the depletion region of a p-n junction?

  Built-in potential
• What are the two terminals of a diode called?

  Anode and cathode
• In a p-n junction, the depletion region has no free charge carriers.

  True
• The built-in potential across the depletion region opposes the flow of current
• The p-n junction structure is the fundamental building block of many semiconductor devices like diodes and transistors.


  True
• In forward bias, the depletion region narrows
• In reverse bias, the depletion region widens
• What is a diode's primary function?

  One-way current flow
• Match the semiconductor type with its doping impurity and charge carriers:

  N-type ↔️ Phosphorus, Electrons

  P-type ↔️ Boron, Holes
• What is the fundamental building block of many semiconductor devices like diodes and transistors?

  p-n junction
• In forward bias, current flows freely above the threshold voltage, which is typically 0.7V
• Steps in the operation of a diode during forward bias

  1️⃣ Positive voltage applied to the anode

  2️⃣ Negative voltage applied to the cathode

  3️⃣ Depletion region narrows

  4️⃣ Built-in potential lowers

  5️⃣ High current flows
• Match the bias mode with its voltage and current characteristics:

  Forward Bias ↔️ Voltage above threshold, current increases exponentially

  Reverse Bias ↔️ Voltage below breakdown, minimal current
• P-type semiconductors are created by doping with acceptor impurities like boron.

  True
• The potential difference across the depletion region in a p-n junction is called the built-in potential
• The built-in potential in a p-n junction opposes the flow of current.


  True
• What type of voltage is applied to the anode in forward bias?

  Positive
• What is a diode?

  A semiconductor device
• What does the diode symbol represent?

  One-way current flow
• What type of impurity is added to form an n-type semiconductor?

  Donor impurities
• A p-n junction is formed when a p-type semiconductor is brought into contact with an n-type semiconductor
• The p-n junction structure is used in diodes and transistors.


  True
• Doping with donor impurities in semiconductors increases the number of positive charge carriers.

  False
• What is created at the interface of a p-n junction when a p-type semiconductor meets an n-type semiconductor?

  Depletion region
• What type of charge carriers are present in an n-type semiconductor?

  Electrons
• In forward bias, a positive voltage is applied to the anode
• In reverse bias, a negative voltage is applied to the anode
• Match the bias mode with its characteristics:

  Forward Bias ↔️ Depletion region narrows

  Reverse Bias ↔️ Depletion region widens
• Semiconductors are formed through a process called doping
• What is the majority charge carrier in a p-type semiconductor?

  Holes
• The depletion region in a p-n junction has a built-in potential
• What type of voltage is applied to the anode and cathode in forward bias?

  Positive to anode, negative to cathode
• Minimal current flows in reverse bias, typically in the nanoamp range.


  True
• Minimal current flows in reverse bias due to the increased built-in potential.


  True
• What type of impurity is added to create n-type semiconductors?

  Donor
• What is formed at the interface of a p-n junction when a p-type and an n-type semiconductor are brought together?

  Depletion region
• A p-n junction is formed when a p-type semiconductor is brought into contact with an n-type semiconductor.