Optimization And Upscaling Of Microlens Arrays For Advanced Photon Detectors

Abstract

Microlens arrays (MLAs) enhance light collection in photon detectors by redirecting incident light to active pixel areas, improving the pixel fill factor and thus the external quantum efficiency. We present recent advancements in MLA optimization and integration for SPADs, SiPMs, and even PICs, addressing diverse substrates and broad optical ranges. A key innovation is the upscaling of MLA fabrication to 200 mm wafers and support for multi-project wafers (MPW), enabling cost-efficient prototyping and industrial compatibility. These capabilities are offered through CSEM’s MLA foundry services, providing design, mastering, and wafer-level replication for next-generation detectors in applications from life sciences to high-energy physics.