Interleaved resistive micro-heater for switching phase-change materials integrated in silicon photonics

Area of Science:

• Photonics
• Materials Science
• Electrical Engineering

Background:

• Phase-change materials (PCMs) offer non-volatile control over optical properties, crucial for advanced photonic integrated circuits (PICs).
• Existing micro-heater designs for PCM switching face limitations in efficiency and device lifetime.
• Applications include photonic switching, RF photonics, and optical information processing.

Purpose of the Study:

• To demonstrate a new electrical switching approach for PCMs in photonic devices.
• To overcome limitations of current micro-heater designs for PCM switching.
• To enable ultra-low power, reconfigurable, and compact PICs.

Main Methods:

• Developed an interleaved resistive micro-heater structure for electrical switching of PCMs.
• Fabricated a proof-of-concept device using a commercial silicon photonics foundry and post-processing.
• Utilized coarse-resolution laser-writing lithography for fabrication.

Main Results:

• Achieved an amplitude switching contrast of 0.775 dB/µm.
• Employed a thin layer (12.5 nm) of GST (Germanium-Antimony-Tellurium).
• Demonstrated an efficient switching mechanism with potential for increased PCM lifetime by eliminating current through the PCM.

Conclusions:

• The novel micro-heater design provides an efficient and potentially longer-lasting method for electrical switching in PCM-based photonic devices.
• This technique facilitates the development of highly reconfigurable and compact photonic integrated circuits.
• The fabrication process is compatible with commercial silicon photonics foundries and requires minimal steps.