The invention relates to the technical field of
photoresist coating of
wafer level packaging, in particular to a fine atomization
resonant cavity structure and a gluing method.The fine atomization
resonant cavity structure comprises a
resonant cavity, a spherical resonant cavity is arranged in the resonant cavity, and the
diameter of the spherical resonant cavity is integer multiples of the half-
wavelength of
ultrasonic excitation; the top end of the resonant cavity is provided with an opening for
ultrasonic excitation input, and the bottom end of the resonant cavity is provided with an
acoustic resonance resonant cavity; and the liquid supply needle is inserted into the
acoustic resonance cavity from the
resonance cavity. According to the structure and the method, the uniformity of
photoresist spraying and the quality of a film layer can be improved, accurate
sound field regulation and control are utilized, a micro-channel is not needed to provide fluid flow, and the potential problem of spray hole blockage is avoided; the
acoustic wave is focused in the resonant cavity, and liquid drops can be broken in an extremely short time, so that the atomization particle size is small, the
concentration ratio is high, and the film thickness of the
photoresist is uniform and controllable; and the film layer uniformity is high, the film layer defects are few, the
conformal coating of the complex three-dimensional
microstructure can be realized without being limited by the surface morphology of the
wafer.