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:
Aug. 12, 2003
Filed:
Apr. 11, 2002
Applicant:
Inventors:
Assignee:
Advanced Micro Devices, Inc., Sunnyvale, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11C 7/00 ; G11C 1/406 ;
U.S. Cl.
CPC ...
G11C 7/00 ; G11C 1/406 ;
Abstract
Methods are disclosed for determining tunnel oxide reliability of flash memory devices in a wafer prior to sorting and packaging without damaging or stressing the devices. The methods comprise measuring an initial threshold voltage of a test cell having the same tunnel oxide as other flash cells on the wafer, applying an erase stress to the test cell for a first time period and a program stress to the test cell for a second time period, and measuring the final threshold voltage of the test cell. The difference between the initial and final threshold voltages is then used to determine or estimate the tunnel oxide reliability of the flash memory cells on the wafer.