Improvement on Size Uniformity of SiO2 Nanospheres Applied in Si Optical Resonance Nanopillar-arrays

Recently, optical resonances of nanostructured semiconductor were proved highly effective for light management in many optoelectronic devices. In this work, the monodispersed silica nanospheres with particle sizes of 270330 nm were synthesized by modified two-step Stober method, and the nanosphere size uniformity was improved by optimizing the synthesis conditions. Then, the as-prepared nanospheres were self-assembled into monolayer as etching mask on the silicon substrate by means of constant temperature heating and evaporation. Finally, Si nanopillararrays were fabricated by inductively coupled plasma etching. The light reflectance spectra show that the fabricated Si nanopillar-arrays with diameters of 300325 nm can excite the quadrupole Mie resonance, and the reflectance of lower than 5% was obtained in visible wavelengths, which show excellent light management performances and can further match the requirements of actual optoelectronic devices.