This paper innovatively proposes a high-precision fabrication strategy for silicon-based micro–nano-composite layered structures composed of micron-scale platforms and nanopillars, effectively addressing the challenges of alignment errors and material mismatch during manufacturing. By integrating electron beam lithography (EBL), inductively coupled plasma (ICP) etching, and ultraviolet nanoimprint lithography (NIL) into a unified multi-step workflow, the method achieves exceptional precision and efficiency in producing complex micro–nano-composite architectures. Comprehensive structural characterization is performed using scanning electron microscopy (SEM) and atomic force microscopy (AFM), with probe convolution effects carefully corrected to ensure accurate dimensional analysis. Experimental results confirm the outstanding stability and uniformity of the fabricated structures, exhibiting minimal deviations in both feature size and spatial layout. Nanopillars with diameters ranging from 50 to 200 nm are successfully integrated onto 1-µm square platforms, with the lateral deviation of 50 nm features maintained within 5% or less. Furthermore, the method effectively mitigates thermal stress-induced misalignment during the fabrication of multi-material layers, demonstrating strong potential for scalable production of advanced photonic devices and integrated nanophotonic systems. Overall, this work establishes a robust and versatile technical pathway for the precise manufacturing and quantitative characterization of micro–nano-composite structures, providing a key foundation for the next generation of photonic integration technologies.

This work systematically investigates photonic nanojet (PNJ) planar arrays formed by periodic arrangements of dielectric microstructures with four geometric configurations: cylinders, cones, truncated pyramids, and pyramids, focusing on the effects of geometry, array arrangement, and array sparsity on PNJ formation and coupling behavior. Full-wave finite-difference time-domain simulations were performed to analyze optical field distributions under different array conditions. The results indicate that under approximately infinite array conditions, different geometries exhibit markedly different coupling responses. Cylindrical and truncated pyramid structures are more susceptible to inter-element scattering, leading to pronounced multistage focusing, whereas pyramid and cone structures maintain higher spatial stability due to dominant localized tip-focusing mechanisms. For the central elements, the maximum PNJ intensity is about 16.4 a.u. for cylindrical structures and 33.5 a.u. for truncated pyramid structures, while significantly higher intensities of approximately 47.5 a.u. and 93 a.u. are achieved for pyramid and cone structures, respectively. In contrast, the FWHM remains nearly constant for all geometries under different array conditions, indicating that lateral focusing is primarily governed by geometry rather than array arrangement. By tuning the array spacing, the inter-element coupling strength can be continuously weakened, and different geometries require distinct sparsity levels to reach the weak-coupling limit. These results establish the dominant role of geometric configuration in PNJ planar arrays and provide guidance for their predictable design.

Previous studies have shown that the external quantum efficiency (EQE) of conventional red Micro-Light emitting diodes(Micro-LEDs) decreases markedly with reducing chip size. This degradation is generally attributed to enhanced non-radiative recombination at sidewall defects, which leads to increased carrier loss in size-scaled LEDs. In this work, AlGaInP quaternary semiconductor epitaxial wafers incorporating multiple quantum wells (MQWs) with different well-layer strain states were grown by metal–organic chemical vapor deposition (MOCVD). Through wafer bonding, photolithography, etching, and metal evaporation, these epitaxial structures were fabricated into Micro-LED arrays with single-pixel pitches of 10, 20, 50, and 100 μm. The experimental results reveal that, with increasing indium (In) composition in the GaInP well layers—corresponding to a gradual increase in lattice mismatch (Δa/a) from 0% to 1%—smaller-sized Micro-LED arrays exhibit superior EQE performance. For devices with a pixel pitch of 10 μm, the EQE of Micro-LED arrays with a 1% lattice mismatch in the well layer is approximately three times higher than that of lattice-matched (0%) counterparts. In contrast, for devices with a pixel pitch of 100 μm, the EQE of lattice-matched (0%) Micro-LED arrays is about 1.3 times higher than that of devices with a 1% lattice mismatch. These results indicate that, to achieve maximum EQE in Micro-LEDs, the strain state of the MQW-layer material must be carefully considered as a priority factor. Optimal device performance requires appropriate matching between LED size and the well-layer growth strain.