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:
Jan. 18, 2005
Filed:
Sep. 18, 2002
Liwu Wang, San Diego, CA (US);
Xiang-ming LI, San Diego, CA (US);
Albert Tian, San Diego, CA (US);
Daniel H. Chang, Rancho Sante Fe, CA (US);
Zhong Zheng, City of Industry, CA (US);
Liwu Wang, San Diego, CA (US);
Xiang-Ming Li, San Diego, CA (US);
Albert Tian, San Diego, CA (US);
Daniel H. Chang, Rancho Sante Fe, CA (US);
Zhong Zheng, City of Industry, CA (US);
AEM, Inc., San Diego, CA (US);
Abstract
A dense lead-free glass ceramic that has low dielectric constant and low dielectric loss for producing high-frequency ceramic devices, such as inductors and low temperature co-fired ceramics (LTCC), is disclosed. The glass ceramic consists of 15-35% by weight of lead-free borosilicate glasses with low softening point, 15-35% by weight of lead-free borosilicate glasses with high softening point, 20-80% by weight of combination of amorphous and crystalline SiO-filler (preferably 5-30% by weight of amorphous SiO, 10-50% by weight of crystalline SiO) and 0.1-10% by weight of at least one oxide of AlO, BaO, SbO, VO, CoO, MgO, BO, NbO, SrO and ZnO. The glass ceramic can be densified up to 99% of its theoretical density after firing and is co-firable with conductive metals between 800-900° C. The dense glass ceramic has dielectric constant of 4.2-4.6 and loss tangent (tan δ)<0.0025 at 20 MHz and good thermal/mechanical strength for application in high frequency electronic devices.