Contact metalens for high-resolution optical microscope in semiconductor failure analysis.

The continuous downscaling of electronic devices requires higher-resolution optical microscopic images for semiconductor failure analysis (FA). However, a part of the diffracted light from the measuring pattern in the silicon (Si) substrate cannot be collected due to the total internal reflection (TIR) at the interface between the Si substrate and air. We propose a metalens suitable for FA that improves resolution of optical microscopic images by collecting beyond the critical angle of TIR at the interface. For the proof of concept, we integrated the fabricated metalens into the optical setup of FA and acquired optical microscopic images of FA that clearly show improved resolution.