TY - GEN
T1 - Developments in AlGaN and UV-C LEDs grown on SiC
AU - Saifaddin, Burhan
AU - Zollner, Christian J.
AU - Almogbel, Abdullah
AU - Foronda, Humberto
AU - Wu, Feng
AU - Albadri, Abdulrahman
AU - Al Yamani, Ahmed
AU - Iza, Michael
AU - Nakamura, Shuji
AU - DenBaars, Steven P.
AU - Speck, James S.
N1 - KAUST Repository Item: Exported on 2022-06-28
Acknowledgements: This work was funded by the King Abdulaziz City for Science and Technology (KACST) Technology Innovations Center (TIC) program and the KACST-KAUST-UCSB Solid State Lighting Program. The authors also would like to thank the support of the Solid State Lighting and Energy Electronics Center (SSLEEC) at UCSB. A portion of this work was done in the UCSB nanofabrication facility, part of the NSF NNIN network (ECS-0335765), as well as the UCSB MRL, which is supported by the NSF MRSEC Program (DMR05-20415). This work was also supported by the National Science Foundation Graduate Research Fellowship Program (Grant No. 1650114).
This publication acknowledges KAUST support, but has no KAUST affiliated authors.
PY - 2018/2/15
Y1 - 2018/2/15
N2 - AlGaN-based UV-C LEDs (260-300 nm) remain inefficient compared to InGaN visible LEDs due to optically absorptive layers limiting light extraction, optical polarization, and poor material quality. Sapphire, the most popular substrate material, is transparent and inexpensive but has many disadvantages in material quality and device performance. In contrast, SiC has small lattice mismatch with AlN (∼1%), similar crystal structure, more chemically stable and contains no oxygen, which degrades the IQE and compensates holes. We report low threading dislocations density (TDD) AlN on SiC (TDD < 7x108cm-2) by metalorganic chemical vapor deposition (MOCVD). We demonstrate innovative thin-film flipchip (TFFC) LEDs with 7.8 mW at 95 mA at 278.5 nm grown on AlN/SiC with TDD∼1x109 cm-2. (Respectively, EQE and WPE are 1.8% and 0.6%.) We also demonstrate that KOH roughening does not impact the IV voltage of TFFC LED. KOH roughening enhanced the light extraction efficiency (LEE) by 100% and ∼180% for UV LEDs with 10 nm p-GaN and 5 nm p-GaN, respectively.
AB - AlGaN-based UV-C LEDs (260-300 nm) remain inefficient compared to InGaN visible LEDs due to optically absorptive layers limiting light extraction, optical polarization, and poor material quality. Sapphire, the most popular substrate material, is transparent and inexpensive but has many disadvantages in material quality and device performance. In contrast, SiC has small lattice mismatch with AlN (∼1%), similar crystal structure, more chemically stable and contains no oxygen, which degrades the IQE and compensates holes. We report low threading dislocations density (TDD) AlN on SiC (TDD < 7x108cm-2) by metalorganic chemical vapor deposition (MOCVD). We demonstrate innovative thin-film flipchip (TFFC) LEDs with 7.8 mW at 95 mA at 278.5 nm grown on AlN/SiC with TDD∼1x109 cm-2. (Respectively, EQE and WPE are 1.8% and 0.6%.) We also demonstrate that KOH roughening does not impact the IV voltage of TFFC LED. KOH roughening enhanced the light extraction efficiency (LEE) by 100% and ∼180% for UV LEDs with 10 nm p-GaN and 5 nm p-GaN, respectively.
UR - http://hdl.handle.net/10754/679399
UR - https://www.spiedigitallibrary.org/conference-proceedings-of-spie/10554/2317660/Developments-in-AlGaN-and-UV-C-LEDs-grown-on-SiC/10.1117/12.2317660.full
UR - http://www.scopus.com/inward/record.url?scp=85047824706&partnerID=8YFLogxK
U2 - 10.1117/12.2317660
DO - 10.1117/12.2317660
M3 - Conference contribution
SN - 9781510615939
BT - Light-Emitting Diodes: Materials, Devices, and Applications for Solid State Lighting XXII
PB - SPIE
ER -