High efficiency fabrication of Si microlenses by applying in-situ laser and ultrasonic vibration hybrid diamond cutting

Abstract

Microlens arrays are important component units of new optical systems with the advantageous of small unit size and high degree of integration. In this research, the efficient fabrication of microlens arrays on hard and brittle material of silicon is achieved by coupling high efficiency ultrasonic elliptical vibration trajectory with in-situ laser softening technology. Firstly, the generation mode and morphology characteristics of the microlens array are fitted by the numerical calculation. Moreover, the actual machining parameters are furtherly confirmed. Furthermore, the maximum critical depth of cut along each crystal direction of monocrystalline silicon is experimentally verified by grooving investigation for anisotropy. Finally, the high efficiency fabrication of the microlens array on silicon is carried out by applying the in-situ laser-vibration hybrid assisted diamond cutting system, where the experimental results matched well with the simulation results. This work provides a valuable method for fast fabrication of microstructure arrays on hard and brittle materials, which has broad application in precision engineering.