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. 09, 1995
Filed:
Dec. 14, 1992
Thomas L Koch, Holmdel, NJ (US);
Frederick W Ostermayer, Jr, Berkeley Heights, NJ (US);
Donald M Tennant, Freehold, NJ (US);
Jean-Marc Verdiell, Matawan, NJ (US);
American Telephone and Telegraph Company, New York, NY (US);
Abstract
A technique is disclosed for utilizing direct-write electron-beam photolithography and holographic optical exposure to form gratings in optoelectronic structures. The direct-write e-beam process is used to form rectangular grating teeth in a mask substrate, where the mask is then used as a phase mask to transfer the pattern to the optoelectronic device. Advantageously, the utilization of a direct write e-beam technique to form the grating pattern on the photomask allows for the formation of any desired number and location of abrupt phase shifts, multiple grating pitches, alignment fiducials, and any other desired features. Therefore, a single exposure of the direct write e-beam mask allows for a plurality of different grating patterns to be simultaneously printed.