TY - JOUR
T1 - Nitride-Based Microlight-Emitting Diodes Using AlN Thin-Film Electrodes with Nanoscale Indium/Tin Conducting Filaments
AU - Son, Kyung Rock
AU - Lee, Tae Ho
AU - Lee, Byeong Ryong
AU - Im, Hyun Sik
AU - Kim, Tae Geun
N1 - Funding Information:
This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (Grant No. 2016R1A3B 1908249). The authors would like to thank Ji-Eun Moon for designing the Table of Contents graphic.
Publisher Copyright:
© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
PY - 2018/12/6
Y1 - 2018/12/6
N2 - Microlight-emitting diodes (µLEDs) are emerging solutions for both high-quality displays and lighting technologies. However, the overall light output power density of these devices is low, as the emission area is shielded by the p-electrodes required for current injection. In this study, instead of the more conventionally used indium tin oxide (ITO), an AlN thin film with nanoscale conducing filaments (CFs) is used, referred to as CF-AlN, as a transparent conducting electrode (TCE), to enhance the output power density from the same emission area. As a result of this modification, the electroluminescence intensity is enhanced by 10% at an injection current of 10 mA, and the current density is improved by 13% at a forward voltage of 4.9 V, in comparison to the parameters observed with ITO-based µLEDs. This improvement is attributed to the higher transmittance of CF-AlN TCEs, together with efficient hole injection from the p-electrode into the light-emitting layer, through the CFs formed in the AlN layer. In addition, using transmission electron microscopy analyses, the origin of the CFs is directly identified as the diffusion of In and Sn ions, which provides critical insight into the conduction mechanism of AlN-based TCEs.
AB - Microlight-emitting diodes (µLEDs) are emerging solutions for both high-quality displays and lighting technologies. However, the overall light output power density of these devices is low, as the emission area is shielded by the p-electrodes required for current injection. In this study, instead of the more conventionally used indium tin oxide (ITO), an AlN thin film with nanoscale conducing filaments (CFs) is used, referred to as CF-AlN, as a transparent conducting electrode (TCE), to enhance the output power density from the same emission area. As a result of this modification, the electroluminescence intensity is enhanced by 10% at an injection current of 10 mA, and the current density is improved by 13% at a forward voltage of 4.9 V, in comparison to the parameters observed with ITO-based µLEDs. This improvement is attributed to the higher transmittance of CF-AlN TCEs, together with efficient hole injection from the p-electrode into the light-emitting layer, through the CFs formed in the AlN layer. In addition, using transmission electron microscopy analyses, the origin of the CFs is directly identified as the diffusion of In and Sn ions, which provides critical insight into the conduction mechanism of AlN-based TCEs.
KW - Schottky barrier height
KW - fill factor
KW - microlight-emitting diodes
KW - nanoscale conducting filament
KW - transparent conducting electrode
UR - http://www.scopus.com/inward/record.url?scp=85054498377&partnerID=8YFLogxK
U2 - 10.1002/smll.201801032
DO - 10.1002/smll.201801032
M3 - Article
C2 - 30286283
AN - SCOPUS:85054498377
SN - 1613-6810
VL - 14
JO - Small
JF - Small
IS - 49
M1 - 1801032
ER -