3D Customized Silica-Based AFM Probes Fabricated by Selective Laser Etching

Atomic force microscopy (AFM) cantilevers are essential components that function both as force sensors and nanoscale interaction tools that play a critical role in AFM capabilities, sensitivity, and precision. Conventional fabrication techniques for probes, that rely on silicon or silicon nitride bulk micro-machining, generally requires complex fabrication processes associated to low throughput and limited geometric flexibility. Here the development of innovative AFM cantilevers made of silica glass through a novel approach based on selective laser etching is explored, which offers cantilever and tip design flexibility, condense the process into three steps, and reduces the fabrication time and cost while minimizing reliance on complex equipment and clean room facilities. The fabrication and characterization of functional glass cantilevers with thicknesses ranging from 1 to 50 µm and spring constants spanning from 0.02 to 80 N m^-1 is demonstrated. The fabricated glass probes show excellent performance in both AFM imaging and force spectroscopy applications. The simple and fast fabrication approach, highlights the potential of selective laser etching to produce innovative versatile silica-based probes for AFM.