Session:

Chalcogenide phase change materials (PCMs) are truly remarkable compounds whose unique switchable optical and electronic properties have fueled an explosion of emerging applications in electronics and photonics. Key to any application is the ability of PCMs to reliably switch between crystalline and amorphous states over a large number of cycles. While this issue has been extensively studied in the case of electronic memories, current PCM-based optical devices show limited endurance. To understand the failure mechanisms limiting endurance of PCMs specifically in photonic devices, we have developed an on-chip micro-heater platform and an automatic multi-modal characterization system to analyze cycling performance of optical PCMs. Our work revealed directional elemental segregation over extended cycles, and identified morphological instability as a new premature failure mode unique to photonic devices. Reversible switching of large-area PCM devices over 10,000 cycles was demonstrated.

Juejun Hu

Massachusetts Institute of Technology

Appearances