Solid State & Optics Seminar
sponsored by “The Flint Fund Series on Quantum Devices and Nanostructures”
Date : Wednesday, 1/25/23
Time: 1:00 PM
Location: Mason 107 or via Zoom
Zoom Link: https://yale.zoom.us/j/97260166684?pwd=c3lQa0Vub1FrMHZ0eHZyZGE5MFhJUT09
Password: 223945
Dr. Saidur Rahman Bakaul, Raytheon Technologies Research Center
Ferroelectrics to revolutionize next-generation microelectronic devices
The last century witnessed an unprecedented rise of microelectronic devices that transformed our lives into a heavily interconnected, artificial intelligence-dependent, and secured society. From the dawn of the 21st century, progress in the performance metrics (power consumption, capacity, speed, size, etc.) of most microelectronic devices halted as the semiconductor industry has impeded fundamental limits. In this talk, I will discuss how ferroelectric (FE) materials can overcome these limits and further advance the performance of microelectronic devices, particularly those used for logic and memory operations. By harnessing emerging phenomena such as the negative capacitance effect and functional defects such as topological polar orders (e.g., bubbles and skyrmions) in complex oxide (e.g., PbZr1-xTixO3) FEs, it is possible to overcome the fundamental limits of power consumption (the Boltzmann tyranny) in field-effect transistors. These materials have been widely absent in microelectronic devices due to the challenges of integrating them with semiconductor workhorse materials such as silicon. I will describe novel epitaxial layer transfer (ELT) techniques that can solve this long-standing problem. ELT techniques have also enabled complex oxide FE tunnel junctions on silicon that show a record (~ 105%) on/off ratio. Furthermore, I will discuss a flexible complex oxide FE memory device that transcends other contemporary memories by at least 10x improvement for the key metrics of memory operation (e.g., remnant polarization, memory retention time, endurance, and switching time). Lastly, I will discuss the local (sub-100 nm spatial length scale) electronic, mechanical, and structural properties of transferred complex oxides and binary oxide ferroelectric materials (e.g., HfZrO2) and shed light on their pros and cons in the context of microelectronic devices.