The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 11, 2004
Filed:
Oct. 09, 2001
Dong-Hau Kuo, Shou-Feng Hsiang, Hualien, TW;
Chih-Hung Wang, Taipei, TW;
Other;
Abstract
The present invention discloses low-cost ceramic powders prepared by the conventional ceramic processing with ceramic raw materials comprising carbonates, oxides and/or hydroxides of barium (Ba), titanium (Ti), magnesium (Mg) and optionally strontium (Sr), lanthanum (La) and niobium (Nb), and lead titanate (PbTiO ) and/or lead oxide (PbO). The present invention also discloses a ceramic material obtained by the ceramic powder through densification and reduction-reoxidation, which has a dielectric constant of about 20,000 to about 55,000, a dielectric loss tangent (tan &dgr;) of about 0.05 to about 0.25, a low capacitance change with temperature (low TCC) of about −15% to about 10% at a temperature range of −55° C. to 150° C., a resistivity of about 10 &OHgr;·cm to about 10 &OHgr;·cm, and a small grain size of about 0.5 to about 3.5 &mgr;m. The ceramic materials are useful in the production of capacitors or modules having high performance such as high dielectric constants and low TCC values with low cost. The ceramic powder also can mix with a glass component of low melting temperature to form a low temperature co-fired capacitor.