Thermal Reflow Process for Glass Microlens Manufacturing

This fabrication process includes three major steps, i.e., fabrication of glassy carbon molds with arrays of micro size holes, glass compression molding to create micro cylinders on glass substrate, and reheating to form microlens arrays. As compared to traditional polymer microlens arrays, glass microlens arrays are more reliable and therefore could be used in more critical applications. In this research, microlens arrays with different surface geometries were successfully fabricated on P-SK57 (T_g = 493 °C) glass substrate using a combination of compression molding and thermal reflow process. The major parameters that influence the final lens shape, including reheating temperature and holding time, were studied to establish a suitable fabrication process. A numerical simulation method was developed to evaluate the fabrication process.