Functional Surface Structuring
SERS sensor fabrication: SEM image of the Ti-6Al-4V (TC4) surface after irradiation with a progressive
laser scan.
Source: L.Lu, et al. Nanomaterials (2019).
Laser marking using selective laser ablation on a sapphire substrate removing a 10 nm thickness
ceramic layer.
Courtesy of Workshop of Photonics.
Laser surface structuring is a versatile technique used to enhance or induce new properties in materials, such as reducing friction, improving lubricant retention, creating diffractive optical structures, producing micro molds for feature replication, modifying surface roughness, and altering hydrophobicity or hydrophilicity. It is also commonly used for marking purposes. Femtosecond laser surface structuring enables these modifications on a variety of materials with ultra-high precision. Due to the extremely short pulse duration and high peak fluence, this method allows for precise structuring of nearly all material classes without generating significant heat-affected zones.
3D profile image of moth-eye structure fabricated on a single-crystalline silicon plate, taken by laser scanning microscope.
Courtesy of prof. Kuniaki Konishi, Institute for Photon Science and Technology, The University of Tokyo.
THz anti-reflection coating fabrication is a laser patterning technique used to reduce Fresnel reflections.
Anti-reflection coatings aimed at reducing Fresnel reflection losses have become essential in the terahertz (THz) region. Implementing such coatings is challenging due to the broad spectrum of the THz signal. Femtosecond lasers enable moth-eye anti-reflection structures, capable of suppressing reflection losses in the range of 0.3 to 2.5 THz for high-resistivity silicon, achieving maximum transmission of 91%. Pyramid-like structures, about 100 µm high, are created on silicon, which is one of the most valuable materials for making optical components such as lenses, windows, and beam splitters, due to its high transparency in the THz region.
No records found.
