Synthesis and characterization of BaTiO3-based X9R ceramics

The relationship between the micro-mechanism and macroscopic dielectric properties in Ba 1−x Bi x Ti 1−x−y Zn 0.75x W 0.25x+y O 3+y systems

“…Due to the small size, low equivalent series resistance (ESR) and low price, multi-layer ceramic capacitors (MLCC) is used in almost everywhere of electronic equipments [6][7][8][9].…”

High dielectric constant and good thermal stability from −55 °C to 450 °C in BaTiO3-based ceramics

“…This puts forward very high requirement for operating temperatures of dielectric materials [1][2][3]. Traditional dielectrics are specified to upper working temperatures of 125℃, 150℃, and 200℃ for X7R, X8R, and X9R capacitors, respectively [4,5]. The first letter in the Electrical Industries Association coding indicates the lower working temperature (X = -55℃), the middle digit designates the upper working temperature (7 = 125℃, 8 = 150℃, and 9 = 175℃), the final letter indicates the variability in capacitance within the given temperature range, with R equating to ±15%.…”

Effect of Ta2O5 and Nb2O5 Dopants on the Stable Dielectric Properties of BaTiO3–(Bi0.5Na0.5)TiO3-Based Materials

“…The utilization of an effective Curie-point shifter, such as (Bi0.5Na0.5)TiO3 or PbTiO3, to increase the Tc point along with the formation of the core-shell structure was found to be an effective method for obtaining high-temperature stability [12][13][14][15][16]. Dielectric formulations, including BaTiO3-based compositions, such as BaTiO3-(Bi0.5Na0.5)TiO3 [5,7,8,14,[17][18][19], BaTiO3-Bi(Zn0.5Ti0.5)O3 [16,20], and BaTiO3-Pb(Ti0.55Sn0.45)O3 [10] systems, and (Bi0.5Na0.5)TiO3-based compositions, such as (Bi0.5Na0.5)TiO3-BaTiO3-CaTiO3 [6,9,21] systems, have been developed recently to meet the temperature coefficient of capacitance (TCC) requirements of the X9R specifications. Another approach was a multi-phase composite consisting of a high-Tc material and a low-Tc material.…”

“…In the BaTiO3-(Bi0.5Na0.5)TiO3 system, (Bi0.5Na0.5)TiO3 shows strong ferroelectricity at room temperature, undergoes a phase transition with a broad dielectric maximum approximately close to 320 °C [8], and is considered as an ideal material to shift the Curie temperature of BaTiO3 above 150 °C [15]. The distortion and deformation of BaTiO3 structure induced by the substitution of Na into Ba sites by (Bi0.5Na0.5)TiO3 addition improves the stable temperature characteristics of the dielectric properties of BaTiO3.…”