Light Guide Layer Thickness Optimization for Enhancement of the Light Extraction Efficiency of Ultraviolet Light–Emitting Diodes
Abstract Consider material machinability and lattice mismatch sapphire as substrates for the ultraviolet-C light-emitting diodes (UV-C LEDs) are commonly used, but their high refractive index can result in the total internal reflection (TIR) of light whereby some light is absorbed, therefore caused...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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SpringerOpen
2021-06-01
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| Series: | Nanoscale Research Letters |
| Subjects: | |
| Online Access: | https://doi.org/10.1186/s11671-021-03563-6 |
| _version_ | 1797706929006444544 |
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| author | Zhi Ting Ye Yuan-Heng Cheng Li-Wei Hung Kung-Hsieh Hsu Yu Chang Hu |
| author_facet | Zhi Ting Ye Yuan-Heng Cheng Li-Wei Hung Kung-Hsieh Hsu Yu Chang Hu |
| author_sort | Zhi Ting Ye |
| collection | DOAJ |
| description | Abstract Consider material machinability and lattice mismatch sapphire as substrates for the ultraviolet-C light-emitting diodes (UV-C LEDs) are commonly used, but their high refractive index can result in the total internal reflection (TIR) of light whereby some light is absorbed, therefore caused reducing light extraction efficiency (LEE). In this study, we propose a method to optimize the thickness of a sapphire substrate light guide layer through first-order optical design which used the optical simulation software Ansys SPEOS to simulate and evaluate the light extraction efficiency. AlGaN UV-C LEDs wafers with a light guide layer thickness of 150–700 μm were used. The simulation proceeded under a center wavelength of 275 nm to determine the optimal thickness design of the light guide layer. Finally, the experimental results demonstrated that the initial light guide layer thickness of 150 μm the reference output power of 13.53 mW, and an increased thickness of 600 um resulted in output power of 20.58 mW. The LEE can be increased by 1.52 times through light guide layer thickness optimization. We propose a method to optimize the thickness of a sapphire substrate light guide layer through first-order optical design. AlGaN UV-C LEDs wafers with a light guide layer thickness of 150–700 μm were used. Finally, the experimental results demonstrated that the LEE can be increased by 1.52 times through light guide layer thickness optimization. |
| first_indexed | 2024-03-12T05:58:39Z |
| format | Article |
| id | doaj.art-7c3d9cd7bfcb448f990288f8985f7ceb |
| institution | Directory Open Access Journal |
| issn | 1556-276X |
| language | English |
| last_indexed | 2024-03-12T05:58:39Z |
| publishDate | 2021-06-01 |
| publisher | SpringerOpen |
| record_format | Article |
| series | Nanoscale Research Letters |
| spelling | doaj.art-7c3d9cd7bfcb448f990288f8985f7ceb2023-09-03T04:20:49ZengSpringerOpenNanoscale Research Letters1556-276X2021-06-011611810.1186/s11671-021-03563-6Light Guide Layer Thickness Optimization for Enhancement of the Light Extraction Efficiency of Ultraviolet Light–Emitting DiodesZhi Ting Ye0Yuan-Heng Cheng1Li-Wei Hung2Kung-Hsieh Hsu3Yu Chang Hu4Department of Mechanical Engineering, Advanced Institute of Manufacturing With High-Tech Innovations, National Chung Cheng UniversityDepartment of Mechanical Engineering, Advanced Institute of Manufacturing With High-Tech Innovations, National Chung Cheng UniversityDepartment of Process Development Division, EPILEDS TECHNOLOGIESDepartment of Process Development Division, EPILEDS TECHNOLOGIESDepartment of R&D Division, Harvatek CorporationAbstract Consider material machinability and lattice mismatch sapphire as substrates for the ultraviolet-C light-emitting diodes (UV-C LEDs) are commonly used, but their high refractive index can result in the total internal reflection (TIR) of light whereby some light is absorbed, therefore caused reducing light extraction efficiency (LEE). In this study, we propose a method to optimize the thickness of a sapphire substrate light guide layer through first-order optical design which used the optical simulation software Ansys SPEOS to simulate and evaluate the light extraction efficiency. AlGaN UV-C LEDs wafers with a light guide layer thickness of 150–700 μm were used. The simulation proceeded under a center wavelength of 275 nm to determine the optimal thickness design of the light guide layer. Finally, the experimental results demonstrated that the initial light guide layer thickness of 150 μm the reference output power of 13.53 mW, and an increased thickness of 600 um resulted in output power of 20.58 mW. The LEE can be increased by 1.52 times through light guide layer thickness optimization. We propose a method to optimize the thickness of a sapphire substrate light guide layer through first-order optical design. AlGaN UV-C LEDs wafers with a light guide layer thickness of 150–700 μm were used. Finally, the experimental results demonstrated that the LEE can be increased by 1.52 times through light guide layer thickness optimization.https://doi.org/10.1186/s11671-021-03563-6Deep-ultraviolet light-emitting diodesLight extraction efficiencyLight guide layerFirst-order optical design |
| spellingShingle | Zhi Ting Ye Yuan-Heng Cheng Li-Wei Hung Kung-Hsieh Hsu Yu Chang Hu Light Guide Layer Thickness Optimization for Enhancement of the Light Extraction Efficiency of Ultraviolet Light–Emitting Diodes Nanoscale Research Letters Deep-ultraviolet light-emitting diodes Light extraction efficiency Light guide layer First-order optical design |
| title | Light Guide Layer Thickness Optimization for Enhancement of the Light Extraction Efficiency of Ultraviolet Light–Emitting Diodes |
| title_full | Light Guide Layer Thickness Optimization for Enhancement of the Light Extraction Efficiency of Ultraviolet Light–Emitting Diodes |
| title_fullStr | Light Guide Layer Thickness Optimization for Enhancement of the Light Extraction Efficiency of Ultraviolet Light–Emitting Diodes |
| title_full_unstemmed | Light Guide Layer Thickness Optimization for Enhancement of the Light Extraction Efficiency of Ultraviolet Light–Emitting Diodes |
| title_short | Light Guide Layer Thickness Optimization for Enhancement of the Light Extraction Efficiency of Ultraviolet Light–Emitting Diodes |
| title_sort | light guide layer thickness optimization for enhancement of the light extraction efficiency of ultraviolet light emitting diodes |
| topic | Deep-ultraviolet light-emitting diodes Light extraction efficiency Light guide layer First-order optical design |
| url | https://doi.org/10.1186/s11671-021-03563-6 |
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