Vibrating Mesh Atomizer for Spin-Spray Deposition

This work presents the development and characterization of a Silicon based MEMS vibrating mesh atomizer for use in Spin-spray deposition of low viscosity liquids. The device design, fabrication process, and application of MEMS atomizer for spin-spray method is discussed. The new spin-spray atomizer is demonstrated using spin on glass and Su-8 photoresist. Spin on glass was used to create a SiO2 layer on silicon substrates with the above-mentioned method. The experimental study compares the new spin-spray method with conventional spin coating based on uniformity, 3D-topography coating, etch rate, film stress, and surface roughness. Low viscosity SU-8 was used to further validate the concept of using the vibrating mesh device to pattern planar and 3D topographical structures. The results demonstrate increased uniformity and less wasted chemicals using spin-spray compared to spin coating deposition. The new vibrating mesh device is smaller, has enhanced droplet size control, easy to integrate into a standard spin coater, and uses less power than traditional ultrasonic spin-spray deposition methods. In addition, the new spin-spray method demonstrated increased conformal coating of 3D microstructures of >40 mu m thick structures compared to standard spin coating.