Phase-change devices for simultaneous optical-electrical applications.

We present a viable pathway to the design and characterization of phase-change devices operating in a mixed-mode optical-electrical, or optoelectronic, manner. Such devices have potential applications ranging from novel displays to optically-gated switches to reconfigurable metamaterials-based devices. With this in mind, a purpose-built optoelectronics probe station capable of simultaneous optical-electrical excitation and simultaneous optical-electrical response measurement has been designed and constructed. Two prototype phase-change devices that might exploit simultaneous optical and electrical effects and/or require simultaneous optical and electrical characterisation, namely a mixed-mode cross-bar type structure and a microheater-based structure, have been designed, fabricated and characterized. The microheater-based approach was shown to be capable of successful thermally-induced cycling, between amorphous and crystalline states, of large-area phase-change devices, making it attractive for practicable pixel fabrication in phase-change display applications.