Power semiconductors

What is the main reason SiC (silicon carbide) is advantageous over Si for high-voltage power devices?

  1. AIts breakdown electric field is about 10 times that of Si
  2. BIts band gap is smaller than that of Si
  3. CIts wafers are cheaper than Si and easier to make in large diameters
Show answer and explanation

Answer: A. Its breakdown electric field is about 10 times that of Si

SiC has a large band gap of about 3.3 eV and a breakdown field about 10 times that of Si. For the same breakdown voltage, the voltage-blocking layer (drift layer) can be thinner and more heavily doped, greatly reducing on-resistance. On the other hand, SiC wafers are more expensive than Si, and larger diameters are still being developed.

Practice this topic Back to topic

More Power semiconductors questions

  1. Which correctly describes an IGBT?
  2. Which is the channel through which current flows in a GaN HEMT?
  3. Which correctly describes the relationship between breakdown voltage and on-resistance in silicon power MOSFETs?
  4. What is the main role of an inverter in power electronics?
  5. In power devices, which loss mainly increases when the switching frequency is raised?