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. 09, 2012
Filed:
Feb. 11, 2010
Sung-nien Kuo, Taipei, TW;
Yuan-yu Hsieh, Hsinchu, TW;
Wen-hsiung Ko, Taichung, TW;
Jih-san Lee, Hsinchu, TW;
Kuei-chi Juan, Hsinchu, TW;
Kuan-cheng Su, Hsinchu, TW;
Sung-Nien Kuo, Taipei, TW;
Yuan-Yu Hsieh, Hsinchu, TW;
Wen-Hsiung Ko, Taichung, TW;
Jih-San Lee, Hsinchu, TW;
Kuei-Chi Juan, Hsinchu, TW;
Kuan-Cheng Su, Hsinchu, TW;
United Microelectronics Corp., Hsinchu, TW;
Abstract
An AC stress test circuit for HCI degradation evaluation in semiconductor devices includes a ring oscillator circuit, first and second pads, and first and second isolating switches. The ring oscillator circuit has a plurality of stages connected in series to form a loop. Each of the stages comprises a first node and a second node. The first and second isolating switches respectively connect the first and second pads to the first and second nodes of a designated stage and both are switched-off during ring oscillator stressing of the designated stage. The present invention also provides a method of evaluating AC stress induced HCI degradation, and a test structure.