Thick-film dielectric and conductive compositions

Abstract

Conductive powder and paste compositions are formed having desirable electrical and physical properties. The conductive powder and paste compositions may be used in combination with dielectric powder and thick-film paste compositions, which are formed having high dielectric constants, low loss tangents, and other desirable electrical and physical properties, to form capacitors and other fired-on-foil passive circuit components.

Description

RELATED APPLICATIONS [0001] This application is related to Application Ser. No. 60 / 418,045, filed in the United States Patent and Trademark Office on Oct. 11, 2002, now U.S. National application Ser. No. 10 / 651,367, and entitled “CO-FIRED CERAMIC CAPACITORS AND METHOD FOR FORMING CERAMIC CAPACITORS FOR USE IN PRINTED WIRING BOARDS,” and Application Ser. No. 60 / 433,105 filed in the United States Patent and trademark Office on Dec. 13, 2002, now U.S. application Ser. No. 10 / 633,551 filed in the United States Patent and Trademark Office on Sep. 16, 2003 and entitled “PRINTED WIRING BOARDS HAVING LOW INDUCTANCE EMBEDDED CAPACITORS AND METHODS OF MAKING SAME”.BACKGROUND [0002] 1. Technical Field [0003] The technical field is circuit components. More particularly, the technical field includes powders and pastes used to form dielectric and conductive elements. [0004] 2. Related Art [0005] Passive components may be embedded in printed wiring board innerlayer panels that are stacked and conn...

AI Technical Summary

Benefits of technology

[0011] The conductive compositions according to the above embodiments can be used to form circuit components such as capacitors. The capacitors can be embedded in printe

Problems solved by technology

Pure barium titanate has its maximum capacitance at its Curie point, which is at 125° C., making pure barium titanate unsuitable for many applications.

Conventional dopants such as barium zirconate, niobium oxide, and strontium titanate may not be suitable for all applications, such as firing at the lower temperatures used in thick-film processing.

For example, conventional multilayer ceramic capacitors with such dopants are typically sintered for two (2) hours or more in air or in reducing atmospheres, at peak temperatures in the vicinity of 1100° C. to 1400° C. The conventional dopants are not effective for fired-on-foil applications performed using nitrogen-based thick-film firing profiles of shorter duration and lower temperatures.

Conventional sintering aid glasses such as lead boro-silicates, however, have lower dielectric constants and their inclusion lowers the dielectric constant of the resulting composite.

The level of glass required for conventional formation of a well-sintered dielectric often results in very low dielectric constants.

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