Fig. 2: The construction of nanoscale HSQ features by FsLDW.
From: λ/30 inorganic features achieved by multi-photon 3D lithography
a Illustration of patterning HSQ with sub-diffraction feature size by FsLDW through nonlinear absorption process. The dashed green line denotes the threshold value of the fs laser induced polymerization. b Scheme of HSQ features fabricated by FsLDW with single-scanning method and cross-scanning method, resulting in 33 nm and 26 nm feature sizes, respectively. When the laser intensity increases, only a portion of the laser spot exceeds the threshold for polymerization, enabling the creation of sub-diffraction features. The blue circle represents the fs laser focus spot size. The inset is the molecular structure of HSQ. c SEM image of HSQ nanowires fabricated by FsLDW with different laser scanning speeds. The inset is the HSQ nanowire with the narrowest linewidth of 33 nm.
