Compound semiconductors

Which material is mainly used in the light-emitting layer of blue LEDs?

  1. AGaAs
  2. BInGaN (GaN-based)
  3. CSi
Show answer and explanation

Answer: B. InGaN (GaN-based)

Blue LEDs use InGaN, GaN with indium added, in their light-emitting layer. GaAs emits in the infrared to red, and Si has an indirect band gap, making it unsuitable for light emitters. Combining a blue LED with a yellow phosphor produces a white LED.

Practice this topic Back to topic

More Compound semiconductors questions

  1. What is an advantage of alloy semiconductors such as AlGaAs?
  2. What is a typical application of HEMTs (high electron mobility transistors)?
  3. In GaN devices, which substrates are commonly used for growing the GaN layers?
  4. Which is a characteristic of gallium oxide (Ga2O3), under research as a next-generation power semiconductor material?
  5. What is the approximate wavelength of light emitted by GaAs, which has a band gap of about 1.42 eV?