Towards a dynamically reconfigurable pixelated reflective display: Focused ion beam for phase-change metapixel structures

TL;DR

This paper demonstrates a novel reconfigurable reflective display using pixelated phase-change metasurfaces created with focused ion beam technology, enabling dynamic color and high pixel density for future optical devices.

Contribution

It introduces a method to create reconfigurable pixelated structures on phase-change thin films using focused ion beam, advancing dynamic display technology.

Findings

Successful fabrication of pixelated metasurfaces with height differences

Creation of structural color mimicking RGB pixels

Potential for high-density, energy-efficient reflective displays

Abstract

The switching and optical properties of phase-change thin films are actively investigated for future smart optical devices. The possibility of having more than one stable state, the large optical contrast between phases, and the fast and reversible switching are some attractive properties driving the research interest. Optical devices based on phase change alloys are considered the frontier contenders for tunable photonics. The combination of vivid structural color formation, with partial amorphization/crystallization of phase change alloys, and the associated optical tunability could be integrated into an energy-efficient reflective display device with high pixel density. This work demonstrates a contrast formation due to relative height differences from isolated pixelated structures. A reflective heterostructure device consisting of a low-loss Sb2Se3 alloy on a gold substrate was produced. With a focused ion beam, a pixelated metasurface structure was produced. Moreover, the ability to create local height differences using an ion beam was employed to create a structural color combination mimicking traditional LED like RGB pixels. We believe our approach in creating metapixels on phase change thin film surfaces could open up research interest in phase change alloys and moving away from semi/static plasmonic systems into truly dynamic display devices.