Ferroic Materials for Smart Systems. Jiyan Dai

1.14a, SMAs activated by heat were developed that would allow for full chevron immersion in jet flow during high thrust requirements (e.g. during take‐off) and not immersing it during cruise where the thrust efficiency is of greater importance (Anon n.d.).

Figure 1.14 (a) Brace of orthodontia using shape memory alloys and (b) arthrodesis device developed by Karnes et al.

For broken bone rehabilitation, a SMA plate with a memory transfer temperature close to body temperature can be attached to both ends of the broken bone as shown in Figure 1.14b. From body heat, the plate will contract and retain its original shape, therefore exerting a compression force on the broken bone at the place of fracture. After the bone has healed, the plate continues exerting the compressive force and aids in strengthening during rehabilitation (Garlock et al. 2017).

1.5 Scope of This Book

      In Chapters 2–5, fundamentals of ferroelectrics, applications of ferroelectric materials, recent advances, and advanced measurement and testing techniques in ferroelectrics will be introduced. In particular, device applications of ferroelectric materials in thin film form will be introduced including FeRAM, ferroelectric tunneling‐based resistive switching, etc. The recent advances include ferroelectricity in emerging materials such as 2D materials and high‐k gate dielectric material HfO₂, while the advanced characterization technologies include the piezoresponse force microscopy (by imaging and switching ferroelectric domains) and Cs‐corrected transmission electron microscopy (TEM) where atomic level ionic displacement can be identified.

      As the most important property application of ferroelectric materials, fundamentals of piezoelectric physics and engineering considerations for device design and fabrication are introduced in Chapters 6 and 7.

      In Chapter 8, starting with a brief introduction on origin of ferromagnetism and its analogy to ferroelectrics, device applications, particularly for magnetostrictive devices, are introduced.

      Chapters 9 and 10 will introduce the multiferroics of materials possessing both ferromagnetic and ferroelectric orders including single phase and composite materials. In particular, devices based on the integration of ferroelectric and ferromagnetic materials such as multiferroic memory device and ME coupling device for sensor applications will be introduced.

      In Chapter 11, ferroelastic materials represented by SMA and magnetic SMAs as well as their device applications will be introduced.

References

      1 Boyn, S., Grollier, J., Lecerf, G. et al. (2017). Learning through ferroelectric domain dynamics in solid‐state synapses. Nature Communications 8: 1–7.

      2 Chang, C.‐Y. and Chen, T.‐L. (2017). Design, fabrication, and modeling of a novel dual‐axis control input PZT gyroscope. Sensors 17 (11): 2505.

      3 Cho, J. (2018). Amid contradictory forecast: IC insights: ‘Memory chips will grow at annual rate of 5% only on average by 2022’. Seoul, Korea: BusinessKorea.

      4 Garlock, A., Karnes, W.M., Fonte, M. et al. (2017). Arthrodesis devices for generating and applying compression within joints. US 2017/0296241 A1, Available at: https://patents.google.com/patent/US20170296241A1/en.

      5 Li, M., Dong, C., Zhou, H. et al. (2017). Highly sensitive DC magnetic field sensor based on nonlinear ME effect. IEEE Sensors Letters 1 (6): 1–4.

      6 Renesas Electronics Corporation (2017). Renesas electronics achieves large‐scale memory operation in fin‐shaped MONOS flash memory for industry's first high‐performance, highly reliable MCUs in 16/14nm process nodes and beyond.

      7 Wang, Y., Gray, D., Berry, D. et al. (2011). An extremely low equivalent magnetic noise magnetoelectric sensor. Advanced Materials 23 (35): 4111–4114. Available at: https://doi.org/10.1002/adma.201100773.