Chinese Optics Letters, 2016, 14 (5): 052201, Published Online: Aug. 6, 2018
Parallel fabrication of silicon concave microlens array by femtosecond laser irradiation and mixed acid etching Download: 923次
220.4000 Microstructure fabrication 140.7090 Ultrafast lasers 350.3950 Micro-optics 160.6000 Semiconductor materials
Abstract
A method of multi-beam femtosecond laser irradiation combined with modified HF - HNO 3 - CH 3 COOH etching is used for the parallel fabrication of all-silicon plano-concave microlens arrays (MLAs). The laser beam is split by a diffractive optical element and focused by a lens to drill microholes parallely on silicon. An HF - HNO 3 - H 2 SO 4 - CH 3 COOH solution is used to expand and polish laser-ablated microholes to form microlenses. Compared with the HF - HNO 3 - CH 3 COOH solution, the solution with H 2 SO 4 can effectively reduce the etched surface roughness. The morphologies of MLAs at different laser powers and pulse numbers are observed. The image array formed by the silicon microlenses is also demonstrated.
An Pan, Tao Chen, Cunxia Li, Xun Hou. Parallel fabrication of silicon concave microlens array by femtosecond laser irradiation and mixed acid etching[J]. Chinese Optics Letters, 2016, 14(5): 052201.