Interface controlled thermal resistances of ultra-thin chalcogenide-based phase change memory devices

Area of Science:

• Materials Science
• Electrical Engineering
• Nanotechnology

Background:

• Phase Change Memory (PCM) offers advanced storage and in-memory processing, crucial for overcoming the von Neumann bottleneck.
• Data storage in PCMs relies on thermal excitation, but thermal properties at the nanoscale remain under-researched.
• Understanding and controlling thermal transport is key to optimizing PCM performance.

Purpose of the Study:

• To investigate and manage thermal transport in PCM cells by manipulating interfacial thermal resistance.
• To explore the impact of crystal structure transitions in GST on thermal properties.
• To reduce power consumption and operating currents in PCM devices.

Main Methods:

• Experimental measurement of interfacial thermal resistance changes during GST crystal structure transitions.
• Computational simulations to analyze the effect of interfacial resistance on reset current in various device sizes.
• Developing a new strategy to manage thermal transport without additional insulating layers.

Main Results:

• A significant change in interfacial thermal resistance was observed as GST transitioned from cubic to hexagonal crystal structure.
• Effective thermal conductivity was reduced by a factor of 4 due to interfacial resistance manipulation.
• Simulations showed up to 40% and 50% reduction in reset current for 20 nm and 120 nm devices, respectively.

Conclusions:

• Manipulating interfacial thermal resistance is a viable strategy for managing thermal transport in PCM.
• This approach offers a pathway to reduce power and operating currents in next-generation memory devices.
• The findings provide critical thermal insights for PCM design and optimization.