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, 1999
Filed:
Jul. 31, 1997
Jung-Rae Park, Daejeon, KR;
Tae-Hong Kim, Daejeon, KR;
Sang-Seok Lee, Daejeon, KR;
Tae-Goo Choy, Daejeon, KR;
Electronics and Telecommunications Research Institute, Daejeon, KR;
Korea Telecom, Seoul, KR;
Abstract
A material for microwave band devices used by the general people and in industrial electronic apparatuses is disclosed. Particularly, a magnetic ceramic composition for use in microwave devices, a magnetic ceramics for use in microwave devices and a preparation method therefore are disclosed, in which the saturation magnetization can be easily controlled, and a low ferri-magnetic resonance half line width and an acceptable curie temperature are ensured. The magnetic ceramic composition for microwave devices includes yttrium oxide (Y.sub.2 O.sub.3), iron oxide (Fe.sub.2 O.sub.3), tin oxide (SnO.sub.2), aluminum oxide (Al.sub.2 O.sub.3) and a calcium supply source. The magnetic ceramics for the microwave devices are manufactured by carrying out a forming and a sintering after mixing: yttrium oxide, iron oxide, tin oxide, aluminum oxide and calcium carbonate (or calcium oxide) based on a formula shown below. It has a saturation magnetization of 100-1,800 G at the normal temperature, a temperature coefficient for the saturation magnetization of 0.2%/.degree.C., and a ferri-magnetic resonance half line width of less than 60 Oe, Y.sub.3-x Ca.sub.x/2 Sn.sub.x/2 Fe.sub.5-y Al.sub.y O.sub.12 where 0.1.ltoreq.x.ltoreq.1, and 0.1.ltoreq.y.ltoreq.1.5.