Fraunhofer Institute for Production Technology IPTResearch project "WaferLevelOptics"
The WaferLevelOptics project aims to develop precision glass molding techniques for the replication of micro-optics at wafer level. It is foreseen that the molding of multiple micro-optics on one glass wafer, stacking these to optical systems, bonding them and then dicing them will become the norm for micro-optics manufacturing in future.
Ongoing miniaturization and the need for ever-larger quantities are only two issues which have led to a change in glass optics manufacturing within the last decade. Direct manufacturing techniques such as grinding and polishing are no longer able to meet the requirements of micro-optical components, and so precision glass molding, a replicative approach, has been devised to keep up with technical developments in optics design. Here, a glass gob is formed to the final shape of a lens by applying a molding process at glass-specific temperatures using ceramic moulds. Thus, a large variety of ultra precise optical elements can be manufactured efficiently from glass.
The incorporation of small micro optical lenses into highly precise optical systems requires innovative solutions. Here, the semiconductor industry is a leading example: the manufacturing of thousands of computer chips on one silicon wafer has brought down manufacturing costs considerably, while lowering the handling complexity and costs of systems integration.
For polymer optics, manufacturing at wafer level is already an established process. As such, thousands of small micro optics can be manufactured on wafers of up to six inches long. Since the technology needed to replicate glass wafers is by far more complex than those used for polymer optics, there currently exists no approach to producing glass micro optics at wafer level.
A European consortium was established to implement the idea of wafer level glass molding. Ten partners from six different countries across Europe are working together to accomplish all the necessary developments to facilitate the efficient manufacturing of micro glass optics.