Why not indirect band gap for led

Click For Summary
SUMMARY

Silicon (Si) cannot be used for light-emitting diodes (LEDs) due to its indirect band gap, which results in lower efficiency for light emission. Indirect band gap materials require both available electronic states and phonons to facilitate the necessary momentum change for photon emission, making them less effective for LED applications. This discussion highlights the fundamental limitations of using silicon in optoelectronic devices.

PREREQUISITES
  • Understanding of semiconductor physics
  • Knowledge of band gap types: direct vs. indirect
  • Familiarity with phonon interactions in materials
  • Basic principles of light emission in LEDs
NEXT STEPS
  • Research the properties of direct band gap materials for LED applications
  • Explore alternative materials for LEDs, such as Gallium Nitride (GaN)
  • Study the role of phonons in semiconductor physics
  • Investigate the efficiency metrics of various LED technologies
USEFUL FOR

Students studying semiconductor physics, engineers working in optoelectronics, and researchers interested in LED technology and materials science.

onqun
Messages
12
Reaction score
0
Hey I was studying for my test, in my notes it says si cannot be used for led, because it has indirect band gap.Why indrect band gap is not useful for led?
 
Physics news on Phys.org
It is a less efficient. It requires not only the available states, but the available phonons to provide the necessary change in momentum.

Zz.
 
Thank you very much
 

Similar threads

Graduate Does direct/indirect band gap occur in solids other than semiconductors?
  • · Replies 7 ·
Replies
7
Views
2K
Undergrad Why diode with larger band gap has larger onset potential?
  • · Replies 7 ·
Replies
7
Views
3K
Graduate Why is the band offset of an LED equal to the band gap?
  • · Replies 1 ·
Replies
1
Views
2K
Undergrad Relationship between the depletion region and the band gap of a diode?
  • · Replies 3 ·
Replies
3
Views
6K
Graduate Anisotropy of the effective masses in semiconductors
  • · Replies 2 ·
Replies
2
Views
3K
High School What Does Not Allowed in Quantum Theory Mean Regarding Band Gaps?
  • · Replies 1 ·
Replies
1
Views
4K
Graduate Energy gap between energy bands in solid state physics
  • · Replies 4 ·
Replies
4
Views
6K
How Does Voltage Affect LED Color Through Band Gap Adjustments?
  • · Replies 1 ·
Replies
1
Views
1K
Graduate Criticality, phase transitions and closing bandgap
  • · Replies 6 ·
Replies
6
Views
3K
High School Viewing IR radiation with cell phone cameras
  • · Replies 4 ·
Replies
4
Views
3K