Ba_0.6Sr_0.4TiO₃ Thin Films Deposited by Spray Coating for High Capacitance Density Capacitors

Abstract

Metal-insulator-metal (MIM) capacitors with Ba 0.6 Sr 0.4 TiO 3 (BST) thin films as insulating layers are fabricated using a novel, fast, and low-cost method. On one hand, the process lies in the swift, continuous, and scalable synthesis of BST nanoparticles using the supercritical fluid technology and, on the other hand, the nonpyrolytic spray coating of thin films using colloidal nanocrystals as ink. The authors focus on the deposition process of thin and uniform layer. A dispersed colloidal suspension based on BST nanoparticles is deposited on a hot copper substrate. A 200 nm thick dielectric film is successfully obtained. Electrical characterizations of Cu/BST/Al MIM structure demonstrate a state-of-the-art capacitance density almost reaching 1 mF cm À2 within an operating voltage range of AE1 V. Moreover, an annealing process of the dielectric layer and the final MIM capacitor at 90 C during 15 h brings a significant decrease of the leakage current by three decades from mA cm À2 to mA cm À2 .

Ink‐Based Additive Nanomanufacturing of Functional Materials for Human‐Integrated Smart Wearables

“…Spray coating is a cost-effective printing method feasible for both small-lot prototyping and large-scale manufacturing [183][184][185] of flexible devices, such as organic solar cells, [186][187][188] thin-film capacitors, [189][190][191] conductive interconnects, [76,192,193] and antennas. [194] In spray coating, the functional inks are atomized into microdroplets by compressed air and dispersed in the airflow.…”

Effect of TiO2 grain size on performance of Ba0.5Sr0.5TiO3 based capacitors for energy storage application

“…Barium strontium titanate (Ba 0.5 Sr 0.5 TiO 3 ) has high relative permittivity hence it is a good candidate for insulator material and can enhance specific capacitance (capacitance per unit mass) of MIM capacitor. Ba 0.5 Sr 0.5 TiO 3 is a solid solution of barium titanate (BaTiO 3 ) and strontium titanate (SrTiO 3 ) and can be synthesized by many techniques such as hydrothermal [1,2], solid-state reaction [3,4], spray pyrolysis [5], sol-gel [6][7][8], RF magnetron sputtering [9,10] and so on. Ba 0.5 Sr 0.5 TiO 3 is ferroelectric material having high dielectric constant, high breakdown field strength, low dielectric loss, pyroelectric properties, ferroelectricity and thermal stability and hence it is suitable for applications in ferroelectric random access memories (FRAM), multi-layer ceramic capacitors, tunable filters, microwave phase shifters, opto-electronic device, sensors [11][12][13][14][15][16].…”