Abstract
Ⅲ-nitride materials are of great importance in the development of modern optoelectronics,but they have been limited over years by low light utilization rate and high dislocation densities in heteroepitaxial films grown on foreign substrate with limited refractive index contrast and large lattice mismatches.Here,we demonstrate a paradigm of high-throughput manufacturing bioinspired microstructures on warped sub-strates by flexible nanoimprint lithography for promoting the light extraction capability.We design a flex-ible nanoimprinting mold of copolymer and a two-step etching process that enable high-efficiency fabrication of nanoimprinted compound-eye-like Al2O3 microstructure(NCAM)and nanoimprinted compound-eye-like SiO2 microstructure(NCSM)template,achieving a 6.4-fold increase in throughput and 25％savings in economic costs over stepper projection lithography.Compared to NCAM template,we find that the NCSM template can not only improve the light extraction capability,but also modulate the morphology of AlN nucleation layer and reduce the formation of misoriented GaN grains on the inclined sidewall of microstructures,which suppresses the dislocations generated during coalescence,resulting in 40％reduction in dislocation density.This study provides a low-cost,high-quality,and high-throughput solution for manufacturing microstructures on warped surfaces of Ⅲ-nitride optoelectronic devices.
基金项目
National Natural Science Foundation of China(52075394)
National Key R&D Program of China(2022YFB3603603)
National Key R&D Program of China(2021YFB3600204)
Key Research and Development Program of Hubei Province(2023BAB137)
Knowledge Innovation Program of Wuhan-Basic Research()
National Youth Talent Support Program()
Fundamental Research Funds for the Central Universities()
NETL
NSTL
万方数据