| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 7939070 | Superlattices and Microstructures | 2018 | 8 Pages |
Abstract
The effect of the number of wells on quantum efficiency and forward voltage of vertical green InGaN/GaN multiple quantum wells (MQWs) light-emitting diodes (LEDs) grown on Si substrate has been experimentally investigated. We have prepared three LED samples with 3, 5 and 7 wells. Electroluminescence measurement shows that the LED with 5 wells has the highest external quantum efficiency (EQE) and the lowest forward voltage. It is observed that V-shaped pits grow up in size and density with an increase in quantum well number by means of scan electron microscope. Due to more hole injection via V-shaped pits, a larger area ratio of pits as a result of more number of wells would bring a lower forward voltage and a higher EQE. However, besides the increasing series resistance would bring a higher forward voltage, the interface of MQWs would become rougher and deteriorate the emission efficiency when increasing the wells number.
Keywords
Related Topics
Physical Sciences and Engineering
Materials Science
Electronic, Optical and Magnetic Materials
Authors
Qingfeng Wu, Jianli Zhang, Chunlan Mo, Xiaolan Wang, Zhijue Quan, Xiaoming Wu, Shuan Pan, Guangxu Wang, Junlin Liu, Fengyi Jiang,