The temperature dependence of ferroelectric properties was investigated for (Al_0.8Sc_0.2)N films 9–130nm thick prepared on (111)Pt/TiO _x /SiO₂/Si substrates. The coercive fields (E _c) of these films decreased with increasing measurement temperature up to 523K, irrespective of film thickness, thus realizing polarization switching because the applicable maximum electric field is beyond E _c. As a resultant, remanent polarization (P _r) above 100μCcm⁻² was ascertained for 9nmthick films at 373 and 423K, which is more than 5 times larger than those of HfO₂-based films of the same thickness. The P _r value was almost independent of film thickness when an electric field is applied for switching. In addition, E _c showed a smaller thickness dependence than conventional ferroelectrics, including Pb(Zr,Ti)O₃. The large P _r value beyond 100μCcm⁻² for around 10nmthick films with small degradation against film thickness, as well as the diminished increase in E _c with decreasing film thickness. This showed that (Al_0.8Sc_0.2)N film is a promising candidate for nonvolatile memory applications requiring high-density and low-voltage operation, including capacitor-type memories and ferroelectric tunnel junction-type memories that consist of metal–ferroelectric–metal structure.

研究了在 (111)Pt/TiO _x /SiO ₂ /Si 衬底上制备的 9-130nm 厚的(Al _0.8 Sc _0.2 )N 薄膜的铁电性能的温度依赖性。矫顽场（Ë _Ç）这些膜的随测量温度高达523K，无论薄膜厚度的，从而实现偏振开关，因为适用的最大电场超出降低Ë _Ç。结果，在 373 和 423K 下，9nm 厚薄膜的剩余极化 ( P _r ) 高于 100 μ Ccm ^-2，比 HfO ₂大 5 倍以上 - 相同厚度的薄膜。当施加电场进行开关时，P _r值几乎与薄膜厚度无关。此外，E _c显示出比包括 Pb(Zr,Ti)O ₃在内的常规铁电体更小的厚度依赖性。对于大约 10nm 厚的薄膜，超过 100 μ Ccm ^-2的大P _r值对薄膜厚度的退化很小，以及随着薄膜厚度的减小E _{c 的}增加减少。这表明 (Al _0.8 Sc _0.2 )N 薄膜是需要高密度和低电压操作的非易失性存储器应用的有希望的候选者，包括由金属-铁电-金属结构组成的电容器型存储器和铁电隧道结型存储器。