Ceramic ferroelectric composite material-BSTO-ZnO

US5635433A · kind A · utility

Assignee

• The United States of America as represented by the Secretary of the Army · US

Inventor

• Louise Sengupta · Ellicott City, US

Key dates

• Filing date: Sep 11, 1995
• Grant date: Jun 3, 1997
• Expiry date: Sep 11, 2015

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C04B35/465
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A novel ceramic ferroelectric material having a high dielectric constant, a ow loss tangent, a low threshold voltage, a high nonlinear voltage exponent and a high tunability. The material is a composite comprising Barium Strontium Titanate (BSTO) and zinc oxide (ZnO). The preferred composite is represented by Ba.sub.1-x Sr.sub.x TiO.sub.3 --ZnO, wherein x is greater than 0.00, but less than or equal to 0.75, and wherein the percent weight ratio between BSTO and ZnO ranges from approximately 99%-50% and 1%-50% respectively. The novel materials possess superior electronic properties, and they may be employed in multilayer capacitors, capacitor-varistors, non-volatile computer memory or phased array antenna systems.