This study presents a concept to fabricate micro-lens devices using high-aspect-ratio lithography, extra-hardness electroplating, and hot embossing processes. A bath of electroplating electrolyte will be formulated to fabricate micro-optics mold inserts with extra-hardness Ni-Co alloy. It is a novel method to increase the life of the mold insert during fabricating micro-lens devices. With this high hardness, the mold inserts can resist high abrasiveness and wearness so as to extend the mold cycle life and reduce the idle time of replacing mold plates during fabrications. Therefore, the process of fabrications of micro-lens can be more cost-effective. In this study, parametric effects of reflow time, and temperature on micro-lens profiles will be characterized and discussed. Finally, the optical properties such as focal length of developed micro-lens will be measured and tested.