2025

Wafer-level nanoimprint lithography (NIL) has increasingly become a pivotal technology in the photonic industry, enabling the development of new devices and applications. Leading manufacturers ofc augmented reality devices, optical sensors, and biomedical chips are already leveraging NIL for its flexibility and efficiency. UV-NIL, in particular, excels at replicating complex micro- and nano-scale structures without compromising mass manufacturability. Recent advancements in the supply chain for
high index resists and substrates have further enhanced the capabilities of this technology. [1] Another key-enabling technology in the field of nanoimprint lithography (NIL) is the NIL Step&Repeat process. Typically, masters for wafer-level NIL replication are fabricated using technologies such as e-beam lithography, diamond turning, or two-photon polymerization. As the geometries and designs of diffractive surface relief gratings for in- and outcoupling structures in next-generation waveguides become increasingly complex, the traditional mastering technologies are proving to be both time- consuming and costly. The NIL Step&Repeat process offers a transformative approach to high-volume manufacturing (HVM) by enabling the replication of a single die - fabricated using techniques such as electron beam lithography (EBL) - onto a new carrier (200mm/300mm).[2] This replicated carrier can then serve as a master template for the actual HVM NIL replication process. Recent developments by various material suppliers have significantly broadened the applications of Nano Imprint Lithography (NIL).[3] Not only can NIL facilitate subsequent etch transfers into high refractive coatings such as titanium oxide, amorphous silicon, or silicon nitride.[4] Additionally, it is feasible to directly replicate nanostructures using functional materials, including high and low refractive index resins or blue light self-emitting quantum dot polymers. This work focuses on demonstrating the upscaling process from a single augmented reality (AR) die to a fully populated NIL Step&Repeat master, followed by high-volume manufacturing HVM-ready and wafer-level NIL replication. Additionally, this work will explore the potential of NIL for structuring etching masks as well as nanopatterning functional and permanent polymers. These advancements highlight the versatility and efficiency of NIL in fabricating complex photonic structures and support the development of next-generation AR devices.