A novel facile technique is proposed for fabricating three-dimensional (3D) concave nanolens arrays on a silicon substrate. The technique leverages an inherent characteristic of the polymethyl methacrylate (PMMA) resist during inductively coupled plasma (ICP) etching. The tendency for plasma ions to accumulate at the edge of the PMMA resist helps create a local electric field that cau... https://leoners.shop/product-category/trundle/