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. 08, 1984
Filed:
Sep. 24, 1982
Robert S Wagers, Richardson, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A broad band surface acoustic wave (SAW) device has an edge-deposited transducer (EDT) capable of frequencies in excess of 1 GHz and bandwidths in the hundreds of MHz. The device includes a transducer on a semiconductor substrate which is either non-piezoelectric or weakly piezoelectric. The substrate has a sharp, smooth edge formed by the intersection of its top and a side surface. The transducer includes a passivation layer deposited on the side surface of the substrate and a starter layer deposited on the passivation layer; an inner metallic (gold, for example) electrode deposited on the starter layer; a transducer layer deposited on the inner metallic electrode; and an outer metallic electrode deposited on the transducer layer. The outer electrode is formed on the transducer layer one-fifth wavelength below the top surface of the substrate. When the transducer is excited, bulk longitudinal waves are generated in the transducer layer which couple to the longitudinal component of the surface wave in the substrate causing the SAW mode to propagate away from the transducer.