A 3D simulation comparison of carrier transport in green and blue c-plane multi-quantum well nitride light emitting diodes
Abstract
Until recently, the electrical efficiency of green nitride light-emitting diodes (LEDs) was considerably lower than that of blue LEDs. This is particularly surprising as one would expect a reduced forward voltage with increasing emission wavelength. In this paper, we theoretically investigated the impact of the number of quantum wells on the forward voltage of III-nitride LEDs with x = 0.15 (blue) and x = 0.24 (green) InxGa1–xN QWs. The simulated dependence of current density (J) on applied diode bias (V) shows a significant increase of 1.9 V in the forward voltage between one and five quantum well (QW) c-plane green LED structures. Artificially turning off the polarization fields in the simulation does not entirely suppress this effect. Due to the large band offsets in the green LED multiple QW stack, simulations indicate a sequential band filling of the QW sequence. This mechanism should not be limited to c-plane LEDs and could also be present in nonpolar or semipolar devices.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Dec 17, 2020
- Source ID
- 10.1063/1.5143276
Entities
People
- Cheyenne Lynsky
- Claude Weisbuch
- Guillaume Lheureux
- James S. Speck
- Yuh-Renn Wu
Organizations
- Air Force Office of Scientific Research
- Division of Materials Research
- National Science Foundation Division of Mathematical Sciences
- National Science and Technology Council
- Simons Foundation
- United States Department of Energy
- École polytechnique