No‐Heating Deposition of 1‐μm‐Thick Y‐Doped HfO2 Ferroelectric Films with Good Ferroelectric and Piezoelectric Properties by Radio Frequency Magnetron Sputtering Method. Issue 10 (14th January 2022)

• Record Type: Journal Article
• Authors: Shimura, Reijiro; Mimura, Takanori; Tateyama, Akinori; Shiraishi, Takahisa; Shimizu, Takao; Yamada, Tomoaki; Tanaka, Yoshitomo; Inoue, Yukari; Funakubo, Hiroshi
• Other Names: Barabash Sergey V. guestEditor.; Park Min Hyuk guestEditor.; Schenk Tony guestEditor.
• Is Part Of: Physica status solidi. Volume 16:Issue 10(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-01-14
• Subjects: 1 μm-thick films -- HfO2 ferroelectric -- no-heating deposition -- piezoelectricity; Solid state physics -- Periodicals; 530.4105
• DOI: 10.1002/pssr.202100574
• Languages: English
• ISSNs: 1862-6254

Abstract

Abstract : Y‐doped HfO2 ferroelectric films of ≈1 μm thick are deposited without heating by a radio frequency magnetron sputtering method. {100}‐oriented epitaxial films with orthorhombic phase are grown on (100)ITO//(100)YSZ substrates without heating. Their crystal structure is almost unchanged after postheat treatment at 800 °C. Ferroelectricity is confirmed for the no‐heating‐deposited films by polarization−electric field ( P−E ) curves, and their remanent polarization ( P r ) and coercive fields are 12 μC cm −2 and 1.5 MV cm −1, respectively. These values are also almost unchanged after the postheat treatment. However, the postheat‐treated films show a lower breakdown electric field compared to the as‐deposited films without heat treatment. Approximately 1 μm‐thick films are also prepared without heating on (111)ITO/(111)Pt/TiO x /SiO2 /(100)Si and (111)Pt/TiO x /SiO2 /(100)Si substrates. Almost pure orthorhombic/tetragonal phase is deposited on both substrates without heating. The P r value of the film on the (111)ITO/(111)Pt/TiO x /SiO2 /(100)Si substrate is about 1.5 times larger than that on the (111)Pt/TiO x /SiO2 /(100)Si substrate due to the better crystallinity of the film lattice‐matched with the underlying ITO layer. The effective piezoelectric constant ( d 33, f ) of the film deposited on the (111)ITO/(111)Pt/TiO x /SiO2 /(100)Si substrate without heating is estimated to be 4 pm V −1 . The present low process temperature leads us to expect novel applications, especially for low‐heat‐resistance applications. Abstract : Y‐doped HfO2 ferroelectric films of ≈1 μm thick are deposited without heating by a radio frequency magnetron sputtering method. The effective piezoelectric constant ( d 33, f ) of the film deposited on the (111)ITO/(111)Pt/TiO x /SiO2 /(100)Si substrate without heating is estimated to be 4 pm V −1 . The present low process temperature leads us to expect novel applications, especially for low‐heat‐resistance applications.