(Invited) Combinatorial Synthesis and Interface Analysis for Development of High Dielectric Constant Thin Films

• Published in: ECS transactions Vol. 108; no. 2; pp. 61 - 68
• Main Authors: Nagata, Takahiro, Kumaragurubaran, Somu, Takahashi, Kenichiro, Ri, Sung-Gi, Chikyow, Toyohiro
• Format: Journal Article
• Language: English
• Published: The Electrochemical Society, Inc 20.05.2022
• ISSN: 1938-5862; 1938-6737
• DOI: 10.1149/10802.0061ecst

The development of high-dielectric constant film materials is essential for future active and passive nanoelectronics devices. By integrating combinatorial synthesis, high throughput material development, and interface analysis, we have developed a high-dielectric constant Bi-based relaxor ferroelectric film material, x [BaTiO 3 ]–(1− x )[Bi(Mg 2/3 Nb 1/3 )O 3 ] (BT–BMN), for film capacitors. To increase the dielectric constant, and its thermal stability, of the above relaxor ferroelectric films, a periodic Ta doping structure was introduced by combinatorial method. The periodic insertion of BT–BMN layers with a high Ta concentration eliminated the dielectric constant decrease and also the Bi segregation encountered in BT–BMN films under high-temperature conditions. Upon optimizing the BT/BMN ratio in the stack structure, the BT–BMN films exhibited a high dielectric constant (>500) and an excellent thermal stability, less than 8% in the temperature range from room temperature to 400 °C