Seminar & Colloquium
[세미나: 2월 2일(목), 오후 3시] NaMLab, Dr. Uwe Schroeder
Title
Ferroelectric Hafnium/Zirconium Oxide: From Memory Devices to Emerging Applications
Speaker
Dr. Uwe Schroeder, Nanoelectronic Materials Laboratory, NaMLab
Education
- 1995 Ph.D. in Surface Science on Pt-Cu Alloy Surfaces, University Bonn
- 1990 Diplom (Master) in Physics, University Bonn
Professional Experience
- 2009-present Senior Scientist/Deputy Scientific Director, Namlab
- 2000-2009 Senior Scientist Infineon/Qimonda, Project manager High k Development for future DRAM memory
- 1997-2000 Scientist Siemens, Development Engineer High k Dielectrics/IBM Development Alliance Fishkill New York
- 1995-1997 Postdoctoral Researcher University of Chicago, Prof. Dr. P. Guyot-Sionnest
- 1993-1994 Research Scientist University of California, Prof. Dr. G. Somorjai Berkeley
| Date | Thursday, February 2nd, 2023
| Time | 15:00 ~
| Venue | 33동 125호 (WCU 다목적실)
[Abstract]
The interest in ferroelectric doped HfO2 and ZrO2-based devices is growing with the recent discovery of the ferroelectric and field-induced ferroelectric properties in both materials. In addition to various dopants in both materials, it was found that the content of oxygen vacancies, stress and strain, surface and bulk effects, and quenching are beneficial for forming the polar phase. Since ferroelectric properties were first found for nanometer-scaled films, deposition techniques and crystallization anneals had to be optimized to extend the occurrence of the polar phase from the 1 nm scale to the bulk material. Transmission electron, electrical characterization, and piezo force microscopy studies reveal single grain/domain nucleation-limited switching kinetics with slightly different coercive fields for different single grains.
The newly found properties of HfO2, even below 10 nm film thickness, enabled an increasing number of applications like high aspect ratio ferroelectric capacitors (FeCap) and field-effect transistors (FeFET) in 2x nm technology nodes. But also, further applications like ferroelectric tunnel junctions and neuromorphic, piezo-, and pyroelectric devices are in discussion. Several devices could be realized on smaller technology nodes and in larger memory arrays. From detailed reliability characterization, a complete picture of the dynamics of the ferroelectric oxide/metal interface can be presented, which unifies the main reliability issues, field cycling endurance, and retention for HfO2¬based films in ferroelectric random-access memory. For future devices beyond conventional CMOS, we need to expand the concept of the interconnect as an active building block for the advanced packaging and 3D integration because the improved performance and built-in flexibility in each chip will eventually provide freedom to the overall system design optimization.
| Host | 박민혁 교수(02-880-7160)