Preparation of YbAlN piezoelectric thin film by sputtering and influence of Yb concentration on properties and crystal structure. Issue 11 (1st June 2021)

• Record Type: Journal Article
• Authors: Uehara, Masato; Amano, Yuki; Anggraini, Sri Ayu; Hirata, Kenji; Yamada, Hiroshi; Akiyama, Morito
• Is Part Of: Ceramics international. Volume 47:Issue 11(2021)
• Page Start: 16029
• Page End: 16036
• Publication Date: 2021-06-01
• Subjects: Piezoelectricity -- Aluminum nitride -- Design of experimental -- Sputtering -- Crystal structure -- And ytterbium; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2021.02.177
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: Aluminum nitride (AlN) is a key material for piezoelectric micro-electromechanical systems (MEMS). Since the discovery of the increase in AlN piezo performance by scandium (Sc) doping, many groups have investigated other effective dopants. However, another effective single dopant has not yet been experimentally demonstrated, although potential effectiveness has been indicated by theoretical calculations. In this study, we propose ytterbium (Yb) as an effective dopant. The sputtering conditions for Yb x Al1 − x N films were optimized by design of experiments (DoE). Consequently, high-quality Yb x Al1 − x N films were obtained. Yb x Al1 − x N with x values ranging from 0 to 0.37 demonstrate good piezo response. A maximum d 33 of ~12 pC/N, which is approximately twice the value of non-doped AlN, is achieved. According to crystallographic analysis using X-ray diffraction, the influence of Yb concentration on the crystal structure was similar to that of Sc with differences observed at high Yb concentration.