Defect Formation of Light-Emitting Particles during the Synthesis of a Hierarchical Porous Surface of ZnO/SiO₂/Si Structures

Abstract

The formation of structures of different sizes on the surface of a single sample and the study of the mechanisms of their excitations and energy transitions is a promising area of research. ZnO/SiO2/Si heterostructures were formed by two-stage electrochemical etching of silicon wafers and synthesizing zinc oxide nanoparticles using sol-gel technology. By scanning electron and atomic force microscopies, various pores and clusters were identified. The presence of five levels of surface hierarchy provided the synthesis of light-emitting particles with different properties. Light emission mechanisms are associated with the recombination of excitons and the hyperfine structure of charged particles trapped on oxygen vacancy.

Keywords

• ZnO
• photoluminescence
• exciton
• oxygen vacancies
• porous silicon