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. 21, 2003
Filed:
Nov. 21, 2002
Jeffrey W. Honeycutt, Boise, ID (US);
Steven M. McDonald, Meridian, ID (US);
Micron Technology, Inc., Boise, ID (US);
Abstract
The use of a resist latent image alignment mark in lieu of using dedicated discrete alignment targets defined on a semiconductor wafer and the use of field oxide step heights for alignment during the fabrication of circuit devices are disclosed. A resist latent image alignment mark is formed in a layer of photoresist material and utilized to position a mask for exposing portions of the photoresist to a radiation source to pattern locations for active areas on a semiconductor substrate. A LOCOS isolation structure is then formed around the active areas. The isolation structure is formed such that the depth of the isolation structure is adjusted to a particular radiation source wavelength. The depth of the isolation structure can then be used as a diffraction grating for stepper alignment. Isolation structure height may also be used as a diffraction grating for stepper alignment.