GaN-Based Blue Light-Emitting Diodes with an Electron Transmission Layer

In this study, GaN-based blue light-emitting diodes (LEDs) with an n-GaN electron transmission layer (ETL) grown between prestrain layer and multiple quantum wells region were fabricated and investigated. As the thickness of ETL increased from 15 to 45 nm, the LEDs generated a 2DEG-like structure with better current spreading ability presented a lower forward voltage of 3.18 V, the light output power (LOP) was improved by 12.5%, and efficiency droop was less than the others. However, as the concentration of ETL increased from 2 x 10(18) to 5 x 10(18) cm(-3), the LEDs performed an obvious decrease in LOP and increase in efficiency droop due to the serious electron overflow. On the other hand, the low temperature electroluminescence and hot/cold factors of LEDs with 45-nm-thick ETL also exhibited better properties, and its hot/cold factor was still quite high (0.87) even at an injection current of 700 mA. (c) 2017 The Electrochemical Society. All rights reserved.