p-doping-free InGaN/GaN light-emitting diode driven by three-dimensional hole gas

• Main Authors: Sun, Xiao Wei, Demir, Hilmi Volkan, Zhang, Zi-Hui, Kyaw, Zabu, Liu, Wei, Tan, Swee Tiam, Ji, Yun, Ju, Zhengang, Zhang, Xueliang
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2015
• Online Access: https://hdl.handle.net/10356/96223; http://hdl.handle.net/10220/38580
• Institution: Nanyang Technological University

Here, GaN/AlxGa1-xN heterostructures with a graded AlN composition, completely lacking external p-doping, are designed and grown using metal-organic-chemical-vapour deposition (MOCVD) system to realize three-dimensional hole gas (3DHG). The existence of the 3DHG is confirmed by capacitance-voltage measurements. Based on this design, a p-doping-free InGaN/GaN light-emitting diode (LED) driven by the 3DHG is proposed and grown using MOCVD. The electroluminescence, which is attributed to the radiative recombination of injected electrons and holes in InGaN/GaN quantum wells, is observed from the fabricated p-doping-free devices. These results suggest that the 3DHG can be an alternative hole source for InGaN/GaN LEDs besides common Mg dopants.