Laser fabrication of nanobump arrays on Si substrate via optical near-field enhancement

Abstract

The paper reports on the fabrication of silicon nanobumps on an n-doped (100) Si wafer with silica microspheres. In the process, a single 248 nm excimer laser pulse was applied on a self-assembled monolayer of 1.5-µm-diameter silica microspheres on a n-doped (100) Si wafer. After laser irradiation at a fluence of 300 mJ/cm2, a regular array of conical Si nanobumps surrounded by a ring shaped trench were fabricated. The structure of the nanobump arrays was characterized by scanning electron microscope, and atomic force microscope. The formed nanobumps were determined to be Si-based bumps with energy disperse spectroscopy. The mechanisms involved in the formation of nanobumps were discussed. The developed Si nanobump pattern has potential applications for sensitive detectors, efficient photovoltaic cells, field-emitter arrays, and displays.The paper reports on the fabrication of silicon nanobumps on an n-doped (100) Si wafer with silica microspheres. In the process, a single 248 nm excimer laser pulse was applied on a self-assembled monolayer of 1.5-µm-diameter silica microspheres on a n-doped (100) Si wafer. After laser irradiation at a fluence of 300 mJ/cm2, a regular array of conical Si nanobumps surrounded by a ring shaped trench were fabricated. The structure of the nanobump arrays was characterized by scanning electron microscope, and atomic force microscope. The formed nanobumps were determined to be Si-based bumps with energy disperse spectroscopy. The mechanisms involved in the formation of nanobumps were discussed. The developed Si nanobump pattern has potential applications for sensitive detectors, efficient photovoltaic cells, field-emitter arrays, and displays.