Table 1 Advanced fabrication technologies for InGaN micro-LEDs
From: Advanced technologies in InGaN micro-LED fabrication to mitigate the sidewall effect
Techniques following ICP-RIE process | Remove damaged layer | KOH28 | TMAH32 | H3PO439 |
(NH4)2S92 | NH4OH94 | HF100 | ||
HCl101 | Octadecylthiol104 | Parylene105 | ||
Passivate sidewall surface | PECVD | SiO2109 | ||
ALD | Al2O3115 | |||
SiO234 | ||||
AlN119 | ||||
Multi-layers | ALD-Al2O3/PECVD-SiO2121 | |||
Al2O3/ZnO122 | ||||
Thermal ALD-HfO2 or SiO2/plasma-enhanced ALD-SiO2/thermal ALD Al2O3123 | ||||
Sol-gel | SiO2124 | |||
Plasma or ion | N2 plasma127 | |||
N ion128 | ||||
N2O plasma129 | ||||
Thermal annealing | ||||
Control current path | Lateral confinement | SiO2 refill135 | ||
Ta2O5 refill136 | ||||
Buried tunnel junction137 | ||||
ITO/p-GaN junction138 | ||||
Hole injection capability optimization132 | ||||
Contact geometry133 | ||||
p-GaN thinning134 | ||||
H2 plasma139 | ||||
Sidewall electrode140 | ||||
Carrier localization141 | ||||
Techniques without ICP-RIE process | Direct epitaxy | Selective area epitaxy or growth145 | ||
Sapphire nano-membranes156 | ||||
Confined selective epitaxy158 | ||||
Ion implantation | F− implantation162 | |||
Ar+ implantation166 | ||||
He+ implantation167 | ||||
He-based focused ion beam irradiation170 | ||||
Neutral beam etching | Cl2 source174 | |||
Hydrogen iodide source177 | ||||
Atomic layer etching | ||||
Metal-assisted chemical etching | HCl-based etchant and Ru metal catalyst182 | |||
Plasma insulation | CHF3 plasma treatment183 | |||
H2 plasma treatment184 | ||||
Selective thermal oxidation | Air atmosphere186 | |||
