Low loss dielectric materials for microwave applications

US6641940B1 · kind B1 · utility

Assignee

• Intematix Corporation · US

Inventors

• Yi-Qun Li · Danville, US
• Xiao-Dong Xiang · Danville, US
• Yi Dong · Tracy, US
• Shifan Cheng · Dublin, US
• Gang Wang · Milpitas, US
• Ning Wang · Beijing, CN

Key dates

• Filing date: Oct 9, 2001
• Grant date: Nov 4, 2003
• Expiry date: Oct 9, 2021

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C04B2235/761
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

Composition for a solid state material, in bulk and in thin film form, that provides relatively high dielectric permittivity that is tunable with variable electrical field bias, relatively low loss tangent and low leakage current for microwave applications. In a first embodiment, the material is BaySr1−yTi1−xMxO3, where M is a substance or mixture including one or more elements drawn from a group consisting of Ta, Zr, Hf, V, Nb, Al, Ga, Cr, Mo, W, Mn, Sc and Re, and the indices x and y satisfy 0≦x≦1 and 0≦y≦1. A preferred choice is M=Ta, V, W, Mo and/or Nb. In a second embodiment, the material is BaySr1−yTi1−x−zTaxMzO3, where M is a substance or mixture including one or more trivalent elements drawn from a group consisting of Al, Ga and Cr and the indices x, y and z satisfy 0≦x+z≦1 and 0≦y≦1.