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:
Oct. 31, 1989
Filed:
Mar. 15, 1989
Joseph P Lorenzo, Stow, MA (US);
Richard A Soref, Newton Centre, MA (US);
United States of America as represented by the Secretary of the Air Force, Washington, DC (US);
Abstract
This invention describes an infrared lightwave modulation and switching aratus for very rapidly changing the refractive index of a light-transmitting, doped, semiconductor waveguide. Electrical control is exerted by a MIS diode or MISFET. The apparatus includes a transparent crystalline silicon waveguide, an electrically insulating dielectric layer overlaying a portion of that waveguide, and an elongated, conductive gate electrode in contact with the insulator. A gate voltage applied between the semiconductor and gate serves to deplete free charge carriers from the region of the waveguide under the gate. Elongated source and drain electrodes may be added to enhance electro-optic control.