Glass flow behaviors in micro-channels during hot embossing

Abstract

A method is proposed to fabricate the micro-structures of glass with low-cost, mass production and high quality by using hybrid open-mold hot embossing technology. The viscous flow and filling behaviors have a great influence on the deformation of glass micro-structures during hot embossing. The detailed topography characterizations of glass micro-structures were performed to analyze the effect of groove width, types of channel, and processing parameters (embossing temperature, pressure, and holding time) on the deformation and filling modes. The results indicated that glass micro-structures presented a larger deformation at the intersection of mold channels. The deformation ratios of glass micro-structures at the cross channels is 0.25. The larger the groove width, the larger the deformation height of the micro-structures. Also, processing parameters of temperature, pressure, and holding time are strongly correlated with the deformation profile of glass micro-structures. At the conditions of 590 °C, 5 MPa, and 100 s, the maximum aspect ratio of glass micro-structure is about 0.7. Excessive forming stress and residual stress induce the growth of glass cracking, which affects the service life and performance of glass micro-structures. This work provides a better understanding of the relationship between design and fabrication of glass micro-structures.