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:
Dec. 15, 1998
Filed:
May. 22, 1997
Shinji Aono, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
This invention provides TEGs for improving accuracy of lifetime evaluation. The TEGs include a base region <Ba> selectively having a cathode region <C> in the surface portion thereof, and an anode region <A>. The intersection of a center line of the cathode region <C> and the anode region <A> provides a function region <WT> located within the range of 5h, five times as much as a height h of a wafer <W>. The function region <WT> makes a pair with the cathode region <C> and actually serves as an actual anode region for the cathode region <C>. As an area ratio of the cathode region <C> to the function region <WT> is smaller, ON voltage values Vf obtained for respective lifetime values get isolated from each other. Thus, the cathode region <C> is formed so that the area ratio of the cathode region <C> to the function region <WT> is about 1/1750000 to 1/4500.