Compound semiconductors
What is the phenomenon called in which the efficiency of an InGaN LED actually decreases as the current is increased?
- AEfficiency droop
- BBlooming
- CElectromigration
Show answer and explanation
Answer: A. Efficiency droop
The efficiency of InGaN LEDs peaks at relatively low currents and declines as current increases. This is called efficiency droop, mainly attributed to Auger recombination, which becomes significant at high carrier densities, and carrier leakage out of the active region. High-power lighting counters it by, for example, using larger chips to lower the current density.
- A. Correct. It is the decline in efficiency at high current.
- B. Blooming is charge overflow in image sensors.
- C. Electromigration is the movement of metal atoms in wiring caused by current.