1. A Comprehensive Study on the Effect of TiN Top and Bottom Electrodes on Atomic Layer Deposited Ferroelectric Hf0.5Zr0.5O2 Thin Films
- Author
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Jinho Ahn, Harrison Sejoon Kim, Jaidah Mohan, Pil-Ryung Cha, Si Joon Kim, Yong Chan Jung, Kihyun Kim, Namhun Kim, Hyun Yong Yu, Jiyoung Kim, Rino Choi, Chadwin D. Young, Akshay Sahota, and Su Min Hwang
- Subjects
Materials science ,Annealing (metallurgy) ,low thermal budget process ,chemistry.chemical_element ,02 engineering and technology ,Hf0.5Zr0.5O2 ,01 natural sciences ,lcsh:Technology ,law.invention ,TiN electrode ,Barrier layer ,Atomic layer deposition ,law ,0103 physical sciences ,General Materials Science ,Crystallization ,Thin film ,lcsh:Microscopy ,lcsh:QC120-168.85 ,010302 applied physics ,lcsh:QH201-278.5 ,business.industry ,lcsh:T ,021001 nanoscience & nanotechnology ,Ferroelectricity ,ferroelectric film ,chemistry ,lcsh:TA1-2040 ,Electrode ,atomic layer deposition ,Optoelectronics ,lcsh:Descriptive and experimental mechanics ,lcsh:Electrical engineering. Electronics. Nuclear engineering ,0210 nano-technology ,business ,Tin ,lcsh:Engineering (General). Civil engineering (General) ,lcsh:TK1-9971 - Abstract
The discovery of ferroelectricity in HfO2-based materials in 2011 provided new research directions and opportunities. In particular, for atomic layer deposited Hf0.5Zr0.5O2 (HZO) films, it is possible to obtain homogenous thin films with satisfactory ferroelectric properties at a low thermal budget process. Based on experiment demonstrations over the past 10 years, it is well known that HZO films show excellent ferroelectricity when sandwiched between TiN top and bottom electrodes. This work reports a comprehensive study on the effect of TiN top and bottom electrodes on the ferroelectric properties of HZO thin films (10 nm). Investigations showed that during HZO crystallization, the TiN bottom electrode promoted ferroelectric phase formation (by oxygen scavenging) and the TiN top electrode inhibited non-ferroelectric phase formation (by stress-induced crystallization). In addition, it was confirmed that the TiN top and bottom electrodes acted as a barrier layer to hydrogen diffusion into the HZO thin film during annealing in a hydrogen-containing atmosphere. These features make the TiN electrodes a useful strategy for improving and preserving the ferroelectric properties of HZO thin films for next-generation memory applications.
- Published
- 2020