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:
Feb. 09, 2010
Filed:
Jan. 22, 2007
Ian Robert Smith, Los Gatos, CA (US);
Christopher F. Bevis, Los Gatos, CA (US);
Ian Robert Smith, Los Gatos, CA (US);
Christopher F. Bevis, Los Gatos, CA (US);
KLA-Tencor Technologies Corporation, Milpitas, CA (US);
Abstract
An electrical test method and apparatus are disclosed. In the method one or more ring oscillators are formed in one or more layers prior to formation of a metal 1 layer of a semiconductor wafer. The one or more layers comprise the formulation of transistors and local interconnects. One or more test structures are formed in one or more interconnect layers at or after the metal 1 of the semiconductor wafer. Each test structure is coupled to a corresponding one or more ring oscillators. A voltage is applied to one or more non-precision contacts to cause the ring oscillators to oscillate. At-speed performance of one or more test structures is determined from one or more measured signals obtained from the test structures. The electrical test apparatus includes one or more ring oscillators formed in one or more layers prior to formation of a metal 1 comprising the formulation of transistors and local interconnects of a semiconductor wafer and one or more test structures formed in one or more interconnect layers at or after the metal 1 of the semiconductor wafer. Each test structure is coupled to one or more corresponding ring oscillators. A non-precision contact is coupled to the one or more ring oscillators for applying voltage to one or more non-precision contacts to cause the ring oscillators to oscillate.