TY - JOUR
T1 - AlN/ITO-Based Hybrid Electrodes with Conducting Filaments
T2 - Their Application to Ultraviolet Light-Emitting Diodes
AU - Kim, Kyeong Heon
AU - Lee, Tae Ho
AU - Kim, Tae Geun
N1 - Funding Information:
This work was supported by a National Research Foundation of Korea (NRF) grant funded by the Korean Government (No. 2016R1A3B1908249). T.G.K. and K.H.K. conceived and designed the experiment. K.H.K. and T.H.L. prepared the samples and conducted the experiment. T.G.K. and K.H.K. analyzed the data and wrote the manuscript. T.G.K. supervised the experiments and contributed to manuscript preparation. All authors discussed the research progress and reviewed the manuscript.
Publisher Copyright:
© 2017 American Chemical Society.
PY - 2017/7/19
Y1 - 2017/7/19
N2 - A hybrid-type transparent conductive electrode (H-TCE) structure comprising an AlN rod array with conducting filaments (CFs) and indium tin oxide (ITO) films is proposed to improve both current injection and distribution as well as optical transmittance in the UV region. These CFs, generated in UV-transparent AlN rod areas using an electric field, can be used as conducting paths for carrier injection from a metal to a semiconductor such as p-(Al)GaN, which allows perfect Ohmic behavior with high transmittance (>95% at 365 nm) to be obtained. In addition, conduction across AlN rods and Ohmic conduction mechanisms are investigated by analyzing AlN rods and AlN rod/p-AlGaN film interfaces. We apply these H-TCEs to three near-UV light-emitting diodes (LEDs) (385 nm LEDs with p-GaN and p-AlGaN terminated surfaces and 365 nm LED with p-AlGaN terminated surface). We confirm that the light power outputs increase by 66%, 79%, and 103%, whereas the forward voltages reduce by 5.6%, 10.2%, and 8.6% for 385 nm p-GaN terminated, 385 nm p-AlGaN terminated, and 365 nm p-AlGaN terminated LEDs with H-TCEs, respectively, compared to LEDs with reference ITOs.
AB - A hybrid-type transparent conductive electrode (H-TCE) structure comprising an AlN rod array with conducting filaments (CFs) and indium tin oxide (ITO) films is proposed to improve both current injection and distribution as well as optical transmittance in the UV region. These CFs, generated in UV-transparent AlN rod areas using an electric field, can be used as conducting paths for carrier injection from a metal to a semiconductor such as p-(Al)GaN, which allows perfect Ohmic behavior with high transmittance (>95% at 365 nm) to be obtained. In addition, conduction across AlN rods and Ohmic conduction mechanisms are investigated by analyzing AlN rods and AlN rod/p-AlGaN film interfaces. We apply these H-TCEs to three near-UV light-emitting diodes (LEDs) (385 nm LEDs with p-GaN and p-AlGaN terminated surfaces and 365 nm LED with p-AlGaN terminated surface). We confirm that the light power outputs increase by 66%, 79%, and 103%, whereas the forward voltages reduce by 5.6%, 10.2%, and 8.6% for 385 nm p-GaN terminated, 385 nm p-AlGaN terminated, and 365 nm p-AlGaN terminated LEDs with H-TCEs, respectively, compared to LEDs with reference ITOs.
KW - AlN rod array
KW - conducting filament
KW - electrical breakdown
KW - transparent conductive electrode
KW - ultraviolet light-emitting diode
UR - http://www.scopus.com/inward/record.url?scp=85024892460&partnerID=8YFLogxK
U2 - 10.1021/acsami.7b06362
DO - 10.1021/acsami.7b06362
M3 - Article
C2 - 28671809
AN - SCOPUS:85024892460
VL - 9
SP - 24357
EP - 24364
JO - ACS applied materials & interfaces
JF - ACS applied materials & interfaces
SN - 1944-8244
IS - 28
ER -