Please use this identifier to cite or link to this item: http://localhost/handle/Hannan/649548
Title: High-Performance Nitride Vertical Light-Emitting Diodes Based on Cu Electroplating Technical Route
Authors: Liancheng Wang;Enqing Guo;Zhiqiang Liu;Xiaoyan Yi;Guohong Wang
subject: gallium nitride|Chip shaping|light-extraction efficiency|external quantum efficiency|polarization|wet etching.|contact resistivity|vertical light-emitting diodes|current diffusion|p-type high reflective electrode|copper electroplating|surface texturization
Year: 2016
Publisher: IEEE
Abstract: GaN-based vertical-geometry light-emitting diodes (V-LEDs) are considered as ideal candidates for future high-power and high-efficiency lighting devices. However, the optoelectrical performance, yield, and stability of V-LEDs are still inferior than the conventional lateral LEDs (L-LEDs) due to some fabrication process hurdles, such as the p-type reflective electrode, nitrogen-polar (N-polar) n-type contact, surface texturization, insufficient current diffusion, and the foreign conductive substrate transfer. Here, we present a minireview of our long-term efforts on V-LEDs fabrication based on Cu electroplating foreign substrate transfer technical route. The electroplating approach shows its inherent advantages of moderation, flexibility, and reliability, yet still hampered by some technical hurdles specifically for V-LEDs fabrication: nonuniformity, easily thermal deformation, difficult to dice out. Since the foreign substrate transfer process is the most critical step, here, first, we introduced our efforts on Cu electroplating manipulation in detail: optimized the polishing and grinding process, Cu:W pseudoalloy and Cu/Ni bilayer electroplating, hybrid wet-etching plus dry laser scribing, and fully wet-etching approaches. Then, we summarized our investigation results for the p-type reflective electrode, nitrogen-polar (N-polar) n-type contact deposition, surface texturization, and current diffusion boost design. Based on the rationally manipulated process, the assembled V-LEDs show excellent optoelectrical performance: record-low forward voltage (VF, 2.75 V at 350 mA, 3.04 V at 1000 mA, 1 mm2 ), low reverse leakage current (I R, 0.1-0.25 μA at -10 V), high lumen efficiency (115 lm/W at 350 mA), low thermal resistance (RT, 1.58 °C/W for V-LEDs chip and 12.06 °C/W for V-LEDs lamp), high yield (>90%), and long-term stability.
URI: http://localhost/handle/Hannan/138990
http://localhost/handle/Hannan/649548
ISSN: 0018-9383
1557-9646
volume: 63
issue: 3
Appears in Collections:2016

Files in This Item:
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Title: High-Performance Nitride Vertical Light-Emitting Diodes Based on Cu Electroplating Technical Route
Authors: Liancheng Wang;Enqing Guo;Zhiqiang Liu;Xiaoyan Yi;Guohong Wang
subject: gallium nitride|Chip shaping|light-extraction efficiency|external quantum efficiency|polarization|wet etching.|contact resistivity|vertical light-emitting diodes|current diffusion|p-type high reflective electrode|copper electroplating|surface texturization
Year: 2016
Publisher: IEEE
Abstract: GaN-based vertical-geometry light-emitting diodes (V-LEDs) are considered as ideal candidates for future high-power and high-efficiency lighting devices. However, the optoelectrical performance, yield, and stability of V-LEDs are still inferior than the conventional lateral LEDs (L-LEDs) due to some fabrication process hurdles, such as the p-type reflective electrode, nitrogen-polar (N-polar) n-type contact, surface texturization, insufficient current diffusion, and the foreign conductive substrate transfer. Here, we present a minireview of our long-term efforts on V-LEDs fabrication based on Cu electroplating foreign substrate transfer technical route. The electroplating approach shows its inherent advantages of moderation, flexibility, and reliability, yet still hampered by some technical hurdles specifically for V-LEDs fabrication: nonuniformity, easily thermal deformation, difficult to dice out. Since the foreign substrate transfer process is the most critical step, here, first, we introduced our efforts on Cu electroplating manipulation in detail: optimized the polishing and grinding process, Cu:W pseudoalloy and Cu/Ni bilayer electroplating, hybrid wet-etching plus dry laser scribing, and fully wet-etching approaches. Then, we summarized our investigation results for the p-type reflective electrode, nitrogen-polar (N-polar) n-type contact deposition, surface texturization, and current diffusion boost design. Based on the rationally manipulated process, the assembled V-LEDs show excellent optoelectrical performance: record-low forward voltage (VF, 2.75 V at 350 mA, 3.04 V at 1000 mA, 1 mm2 ), low reverse leakage current (I R, 0.1-0.25 μA at -10 V), high lumen efficiency (115 lm/W at 350 mA), low thermal resistance (RT, 1.58 °C/W for V-LEDs chip and 12.06 °C/W for V-LEDs lamp), high yield (>90%), and long-term stability.
URI: http://localhost/handle/Hannan/138990
http://localhost/handle/Hannan/649548
ISSN: 0018-9383
1557-9646
volume: 63
issue: 3
Appears in Collections:2016

Files in This Item:
File Description SizeFormat 
7404263.pdf3.32 MBAdobe PDFThumbnail
Preview File
Title: High-Performance Nitride Vertical Light-Emitting Diodes Based on Cu Electroplating Technical Route
Authors: Liancheng Wang;Enqing Guo;Zhiqiang Liu;Xiaoyan Yi;Guohong Wang
subject: gallium nitride|Chip shaping|light-extraction efficiency|external quantum efficiency|polarization|wet etching.|contact resistivity|vertical light-emitting diodes|current diffusion|p-type high reflective electrode|copper electroplating|surface texturization
Year: 2016
Publisher: IEEE
Abstract: GaN-based vertical-geometry light-emitting diodes (V-LEDs) are considered as ideal candidates for future high-power and high-efficiency lighting devices. However, the optoelectrical performance, yield, and stability of V-LEDs are still inferior than the conventional lateral LEDs (L-LEDs) due to some fabrication process hurdles, such as the p-type reflective electrode, nitrogen-polar (N-polar) n-type contact, surface texturization, insufficient current diffusion, and the foreign conductive substrate transfer. Here, we present a minireview of our long-term efforts on V-LEDs fabrication based on Cu electroplating foreign substrate transfer technical route. The electroplating approach shows its inherent advantages of moderation, flexibility, and reliability, yet still hampered by some technical hurdles specifically for V-LEDs fabrication: nonuniformity, easily thermal deformation, difficult to dice out. Since the foreign substrate transfer process is the most critical step, here, first, we introduced our efforts on Cu electroplating manipulation in detail: optimized the polishing and grinding process, Cu:W pseudoalloy and Cu/Ni bilayer electroplating, hybrid wet-etching plus dry laser scribing, and fully wet-etching approaches. Then, we summarized our investigation results for the p-type reflective electrode, nitrogen-polar (N-polar) n-type contact deposition, surface texturization, and current diffusion boost design. Based on the rationally manipulated process, the assembled V-LEDs show excellent optoelectrical performance: record-low forward voltage (VF, 2.75 V at 350 mA, 3.04 V at 1000 mA, 1 mm2 ), low reverse leakage current (I R, 0.1-0.25 μA at -10 V), high lumen efficiency (115 lm/W at 350 mA), low thermal resistance (RT, 1.58 °C/W for V-LEDs chip and 12.06 °C/W for V-LEDs lamp), high yield (>90%), and long-term stability.
URI: http://localhost/handle/Hannan/138990
http://localhost/handle/Hannan/649548
ISSN: 0018-9383
1557-9646
volume: 63
issue: 3
Appears in Collections:2016

Files in This Item:
File Description SizeFormat 
7404263.pdf3.32 MBAdobe PDFThumbnail
Preview File