Wafer Level Optics

In modern electronic devices such as digital cameras, mobile phones, portable gaming consoles, laptops or netbooks, micro-optical systems are decisive interfaces between the real world and the microelectronics of the image sensor inside a camera module. At present, the general concept of a camera module assembly undergoes a transition from discrete assembly to wafer-level integration using well-established semiconductor technologies. Wafer-level cameras have already started to replace conventional modules due to smaller form factors and lower cost performance ratios.

Wafer level cameras (WLCs) are devices in which all the individual parts are fabricated at wafer level and are then bonded to form one single part consisting of a CMOS image sensor (CIS) and a micro-optics stack enhancing the light capture efficiency of the camera.

UV imprint lithography, originally developed for cost-efficient replication of structures in the nanometer range, is now considered a powerful tool for the fabrication of wafer-level optics in highly parallel mass fabrication processes.

EV Group offers manufacturers a complete range of solutions, including master stamp fabrication, replication and integration of optical elements at wafer level based on its well-established mask alignment and nanoimprint lithography systems. Its product portfolio is highly versatile, enabling customers to implement highly customized hardware and software processes. Coupled with process development and optimization in EV Group's cleanroom facilities, EV Group provides a total solution from system configuration and fabrication to process integration and material know-how.

 

WLO-3D-Grafik-02
Elements of a typical wafer-level camera module include a CMOS image sensor, polymeric lenses molded onto glass carriers by UV imprint lithography, spacers and aperture layers, as shown in this exploded view. Source: EVG.