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:
Apr. 10, 2007
Filed:
Sep. 19, 2005
Atsushi Noma, Osaka, JP;
Atsushi Noma, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A reliability test method for a ferroelectric memory device having a ferroelectric capacitor evaluates, under acceleration conditions (acceleration temperature Tand test time t), whether or not life of retention characteristics of the ferroelectric memory device is guaranteed under actual use conditions (guarantee temperature Tand guarantee time t). The method includes the step of determining test time tthat is required to evaluate whether the life of the retention characteristics is guaranteed or not, based on temperature dependence of change with time of a bit line voltage that is generated when data written to the ferroelectric memory device is read.