Raymond L Mcgowan

US Patent:

51626918, Nov 10, 1992

Filed:

Jan 22, 1991

Appl. No.:

7/643634

Inventors:

Elio A. Mariani - Hamilton Square NJ
Raymond McGowan - Neptune NJ

Assignee:

The United States of America as represented by the Secretary of the Army - Washington DC

International Classification:

H01L 4108

US Classification:

310321

Abstract:

A method and apparatus directed to a thin film piezoelectric resonator deposited on a support layer of dielectric material and being configured in the form of a cantilever structure having a base portion formed on an integrated circuit substrate and having an overhanging beam portion joined at one end to the base portion, with the opposite end being unsupported with an air-gap intermediate the beam portion and the substrate. In the fabrication of the resonator, a thin film of dielectric material, e. g. zinc oxide (ZnO) is first deposited on the substrate, but is subsequently removed from beneath the beam portion resulting in the air-gap which is open on three sides and thus results in a greater ease of fabrication. A completely monolithic chemical detector is implemented utilizing a matched pair of these cantilevered air-gap thin film resonators, with one of the resonators further including a coating on one of its electrodes and which is responsive to a predetermined chemical to cause a frequency shift in the presence of the chemical to be detected. In one embodiment of the chemical detector, the frequency outputs of the two resonators are compared with the difference frequency providing an indication of the chemical being detected.

US Patent:

58214259, Oct 13, 1998

Filed:

Sep 30, 1996

Appl. No.:

8/723068

Inventors:

Elio A. Mariani - Hamilton Square NJ
Raymond C. McGowan - Neptune NJ
James T. Stewart - Nashua NH

Assignee:

The United States of America as represented by the Secretary of the Army - Washington DC

International Classification:

G01L 1100

US Classification:

73703

Abstract:

A surface acoustic wave (SAW) sensing device for remotely sensing structu integrity of a physical structure. The sensing device includes a piezoelectric substrate with a notch formed part way in the bottom of the substrate and along the width thereof. The substrate is mounted to a physical structure of interest. An antenna is coupled to the RF circuit on the substrate and is capable of receiving and transmitting a RF signal. Interdigital input and output transducers are disposed on the upper surface of the substrate. The input transducer is located adjacent one end of the substrate and the output transducer is located adjacent an opposing end of the substrate. Bus bars connect the input and output transducers. The input transducer provides a complementary first response upon receipt of an RF expanded linear/nonlinear FM signal from the antenna and transmits this compressed pulse to the output transducer. The output transducer provides a second response upon receipt of the first response and transmits the same to the antenna via the bus bar.