Pressure-induced emission of dopant-free SU-8 for passive photonic devices

SU-8, a widely used negative-tone photoresist in microelectronics, has low optical loss and excellent processability, making it promising for photonic integrated devices. However, most existing SU-8-based passive photonic devices rely on dye doping to enhance luminescent performance, increasing fabrication complexity. Here, we applied pressure treatment to four types of SU-8 micropatterns prepared by photolithography, which exhibited intense blue-white emission after pressure release and achieved a 15-fold enhancement. This study demonstrates dye-free photoluminescence enhancement in SU-8, providing a new strategy for SU-8-based passive photonic integration.