鐵電材料 ??0.5 ??0.5 ?2 (HZO)在新興的非揮發性記憶體應用中引起了廣泛關注。
然而，關於其在低溫下的特性還缺乏深入的討論。在未來的應用中，例如高效能運算 與量子運算，積體電路與記憶體操作在低溫的環境下是必要的。因此，本研究旨在探 討低溫下鐵電電容的特性，包括可靠性問題，如 Wake-up 效應、保持性、耐久性。
研究中使用三種不同的鐵電電容器，分別在不同的製程條件下進行低溫下的鐵電 性能測量。這些製程條件包括不同的沉積溫度(300°C 與 280°C)以及在金屬-鐵電- 金屬(MFM)結構中額外摻雜釔(Yttrium)。我們探討了不同溫度下觀察到的差異可 能原因。
基於量測結果，我們探討了低溫下鐵電電容器的可能情境，並評估其作為低溫儲 存設備的潛力。

Ferroelectric ??0.5 ??0.5 ?2 (HZO) has attracted significant attention in the emerging non-volatile memory (eNVM) applications. However, there is a lack of in-depth discussion regarding its operation at low temperatures. In future applications such as high-performance computing and quantum computing, operation at low temperatures (< 300 K) is essential. Therefore, this study aims to investigate the electrical characteristics of ferroelectric capacitors at low temperatures, including reliability issues such as the wake-up effect, retention, endurance.
Three different ferroelectric capacitors are fabricated with different deposition conditions. These process conditions include different deposition temperatures (280 and 300 °C) and additional yttrium doping in the metal-ferroelectric-metal (MFM) structure. All MFM capacitors have been measured at different temperatures, from 300 down to 4 K. The impacts of lowering temperature on the ferroelectricity of the fabricated devices are discussed in this work.
Based on the measurement results, the material and device properties of the ferroelectric capacitors at low temperatures are investigated, and their potential as low-temperature storage devices are evaluated.

[1]   P. Lukas, ‘John von Neumann and Modern Computer Architecture’, NCLab. Accessed: Nov. 17, 2023. [Online]. Available: https://nclab.com/john-von-neumann-and-modern-computer-architecture/
[2]   ‘Evaluation of Alternative Vertical Transistors for 3D NAND Applications - KU Leuven’. Accessed: Jun. 05, 2023. [Online]. Available: https://kuleuven.limo.libis.be/discovery/fulldisplay/lirias2790974/32KUL_KUL:Lirias
[3]   K. Florent, ‘Ferroelectric HfO2 for Emerging Ferroelectric Semiconductor Devices’.
[4]   ‘Integration of Ferroelectric and Piezoelectric Thin Films: Concepts and Applications for Microsystems | Wiley’, Wiley.com. Accessed: Jun. 05, 2023. [Online]. Available: https://www.wiley.com/en-us/Integration+of+Ferroelectric+and+Piezoelectric+Thin+Films%3A+Concepts+and+Applications+for+Microsystems-p-9781118616604
[5]   Physics of Ferroelectrics: A Modern Perspective, vol. 105. in Topics in Applied Physics, vol. 105. Berlin, Heidelberg: Springer, 2007. doi: 10.1007/978-3-540-34591-6.
[6]   E. Yurchuk, ‘Electrical Characterisation of Ferroelectric Field Effect Transistors Based on Ferroelectric Hfo2 Thin Films’, Jun. 2015. Accessed: Jun. 05, 2023. [Online]. Available: https://www.semanticscholar.org/paper/Electrical-Characterisation-of-Ferroelectric-Field-Yurchuk/7765649392bf30a7fe65b43593448c9e0382cf7a
[7]   ‘Multi-Physics Properties in Ferroelectric Nanowires and Related Structures from First-Principles | IntechOpen’. Accessed: Jun. 05, 2023. [Online]. Available: https://www.intechopen.com/chapters/10516
[8]   ‘Domains in Ferroic Crystals and Thin Films | SpringerLink’. Accessed: Jun. 05, 2023. [Online]. Available: https://link.springer.com/book/10.1007/978-1-4419-1417-0
[9]   ‘Ferroelectric Memories | SpringerLink’. Accessed: Jun. 05, 2023. [Online]. Available: https://link.springer.com/book/10.1007/978-3-662-04307-3
[10] ‘Understanding a Ferroelectric Hysteresis Loop in Electronics’. Accessed: Nov. 17, 2023. [Online]. Available: https://resources.pcb.cadence.com/blog/2020-understanding-a-ferroelectric-hysteresis-loop-in-electronics
[11] Y.-H. Chen, C.-J. Su, T.-H. Yang, C. hu, and T.-L. Wu, ‘Improved TDDB Reliability and Interface States in 5-nm Hf0.5Zr0.5O2 Ferroelectric Technologies Using NH₃ Plasma and Microwave Annealing’, IEEE Trans. Electron Devices, vol. PP, pp. 1–5, Mar. 2020, doi: 10.1109/TED.2020.2973652.
[12] ‘Recent progress for obtaining the ferroelectric phase in hafnium oxide based films: impact of oxygen and zirconium - IOPscience’. Accessed: Jul. 20, 2023. [Online]. Available: https://iopscience.iop.org/article/10.7567/1347-4065/ab45e3/meta
[13] V. A. Gritsenko, T. V. Perevalov, and D. R. Islamov, ‘Electronic properties of hafnium oxide: A contribution from defects and traps’, Phys. Rep., vol. 613, pp. 1–20, Feb. 2016, doi: 10.1016/j.physrep.2015.11.002.
[14] T. S. Böscke, J. Müller, D. Bräuhaus, U. Schröder, and U. Böttger, ‘Ferroelectricity in hafnium oxide thin films’, Appl. Phys. Lett., vol. 99, no. 10, Art. no. 10, Sep. 2011, doi: 10.1063/1.3634052.
[15] S. J. Kim, J. Mohan, S. Summerfelt, and J. Kim, ‘Ferroelectric Hf0.5Zr0.5O2 Thin Films: A Review of Recent Advances’, JOM, vol. 71, Sep. 2018, doi: 10.1007/s11837-018-3140-5.
[16] A. M. Walke et al., ‘Electrical Investigation of Wake-Up in High Endurance Fatigue-Free La and Y Doped HZO Metal–Ferroelectric–Metal Capacitors’, IEEE Trans. Electron Devices, vol. 69, no. 8, pp. 4744–4749, Aug. 2022, doi: 10.1109/TED.2022.3186869.
[17] M. Tarkov, F. Tikhonenko, V. Popov, V. Antonov, A. Miakonkikh, and K. Rudenko, ‘Ferroelectric Devices for Content-Addressable Memory’, Nanomaterials, vol. 12, p. 4488, Dec. 2022, doi: 10.3390/nano12244488.
[18] D. Zhou et al., ‘Wake-up effects in Si-doped hafnium oxide ferroelectric thin films’, Appl. Phys. Lett., vol. 103, no. 19, p. 192904, Nov. 2013, doi: 10.1063/1.4829064.
[19] D. Martin et al., ‘Ferroelectricity in Si-Doped HfO2 Revealed: A Binary Lead-Free Ferroelectric’, Adv. Mater., vol. 26, no. 48, Art. no. 48, 2014, doi: 10.1002/adma.201403115.
[20] ‘Understanding ferroelectric Al:HfO2 thin films with Si-based electrodes for 3D applications | Journal of Applied Physics | AIP Publishing’. Accessed: Jun. 10, 2023. [Online]. Available: https://pubs.aip.org/aip/jap/article/121/20/204103/153683/Understanding-ferroelectric-Al-HfO2-thin-films
[21] Y. A. Genenko, J. Glaum, M. J. Hoffmann, and K. Albe, ‘Mechanisms of aging and fatigue in ferroelectrics’, Mater. Sci. Eng. B, vol. 192, pp. 52–82, Feb. 2015, doi: 10.1016/j.mseb.2014.10.003.
[22] M. H. Park, Y. H. Lee, T. Mikolajick, U. Schroeder, and C. S. Hwang, ‘Review and perspective on ferroelectric HfO2-based thin films for memory applications’, MRS Commun., vol. 8, no. 3, pp. 795–808, Sep. 2018, doi: 10.1557/mrc.2018.175.
[23] W. L. Warren et al., ‘Polarization suppression in Pb(Zr,Ti)O3 thin films’, J. Appl. Phys., vol. 77, no. 12, pp. 6695–6702, Jun. 1995, doi: 10.1063/1.359083.
[24] D. Dimos, W. L. Warren, and H. N. Al-Shareef, ‘Degradation Mechanisms and Reliability Issues for Ferroelectric Thin Films’, in Thin Film Ferroelectric Materials and Devices, R. Ramesh, Ed., in Electronic Materials: Science and Technology. , Boston, MA: Springer US, 1997, pp. 199–219. doi: 10.1007/978-1-4615-6185-9_8.
[25] ‘Direct observation of region by region suppression of the switchable polarization (fatigue) in Pb(Zr,Ti)O3 thin film capacitors with Pt electrodes | Applied Physics Letters | AIP Publishing’. Accessed: Jun. 11, 2023. [Online]. Available: https://pubs.aip.org/aip/apl/article/72/21/2763/68667/Direct-observation-of-region-by-region-suppression
[26] ‘Polarization fatigue in ferroelectric films: Basic experimental findings, phenomenological scenarios, and microscopic features | Journal of Applied Physics | AIP Publishing’. Accessed: Jun. 11, 2023. [Online]. Available: https://pubs.aip.org/aip/jap/article/90/3/1387/484400/Polarization-fatigue-in-ferroelectric-films-Basic
[27] C. Brennan, ‘Model of ferroelectric fatigue due to defect/domain interactions’, Ferroelectrics, vol. 150, no. 1, pp. 199–208, Dec. 1993, doi: 10.1080/00150199308008705.
[28] A. K. Tagantsev, I. Stolichnov, N. Setter, and J. S. Cross, ‘Nature of nonlinear imprint in ferroelectric films and long-term prediction of polarization loss in ferroelectric memories’, J. Appl. Phys., vol. 96, no. 11, pp. 6616–6623, Nov. 2004, doi: 10.1063/1.1805190.
[29] ‘Ferroelectric thin films: Review of materials, properties, and applications | Journal of Applied Physics | AIP Publishing’. Accessed: Jun. 12, 2023. [Online]. Available: https://pubs.aip.org/aip/jap/article/100/5/051606/974388/Ferroelectric-thin-films-Review-of-materials
[30] ‘Imprint in ferroelectric materials due to space charges: A theoretical analysis | Applied Physics Letters | AIP Publishing’. Accessed: Jun. 12, 2023. [Online]. Available: https://pubs.aip.org/aip/apl/article/95/9/092902/338465/Imprint-in-ferroelectric-materials-due-to-space
[31] ‘The interface screening model as origin of imprint in PbZrxTi1−xO3 thin films. I. Dopant, illumination, and bias dependence | Journal of Applied Physics | AIP Publishing’. Accessed: Jun. 12, 2023. [Online]. Available: https://pubs.aip.org/aip/jap/article/92/5/2680/472083/The-interface-screening-model-as-origin-of-imprint
[32] Y. Ahn and J. Y. Son, ‘Imprint phenomenon of ferroelectric switching characteristics in BaTiO3/PbTiO3 multilayer thin films’, J. Alloys Compd., vol. 891, p. 162088, Jan. 2022, doi: 10.1016/j.jallcom.2021.162088.
[33] I. Stolichnov, A. K. Tagantsev, E. Colla, N. Setter, and J. S. Cross, ‘Physical model of retention and temperature-dependent polarization reversal in ferroelectric films’, J. Appl. Phys., vol. 98, no. 8, p. 084106, Oct. 2005, doi: 10.1063/1.2112174.
[34] A. K. Tagantsev, M. Landivar, E. Colla, and N. Setter, ‘Identification of passive layer in ferroelectric thin films from their switching parameters’, J. Appl. Phys., vol. 78, no. 4, pp. 2623–2630, Aug. 1995, doi: 10.1063/1.360122.
[35] ‘Modeling of depolarization in ferroelectric thin films: Integrated Ferroelectrics: Vol 23, No 1-4’. Accessed: Jun. 12, 2023. [Online]. Available: https://www.tandfonline.com/doi/abs/10.1080/10584589908210139