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:
Dec. 24, 2002
Filed:
Dec. 07, 1999
Hua Jiang, Mansfield, MA (US);
Wei Hu, Cambridge, MA (US);
Shaohua Liang, Somerset, NJ (US);
Yi-Qun Li, Orinda, CA (US);
Vladimir Fuflyigin, Winchester, MA (US);
Jiankang Huang, Cambridge, MA (US);
Corning Applied Technologies Corporation, Woburn, MA (US);
Abstract
A ferroelectric layer is deposited or in close proximity to a ferromagnetic ferrite layer to make a microwave substrate on which conductors can be deposited or placed to make devices. The permittivity of the ferroelectric layer can be changed by applying a voltage and the permeability of the ferromagnetic layer can be changed with a magnetic field. This makes it possible to tune the device characteristics with two different effects taking best advantage of the capabilities of each. A material example is ferromagnetic yttrium-iron-garnet on which is deposited a thin film of ferroelectric barium strontium titanate. To minimize losses, the ferroelectric film should be high quality, but practical yttrium-iron-garnet substrates are polycrystalline so that the use of buffer layers is desirable. At least two methods can be used to deposit the ferroelectric film, pulsed laser deposition and metal-organic chemical liquid deposition. A variety of dual tunable microwave devices can be made with this substrate, including by way of example only, phase shifters, frequency filters, and resonators.