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. 20, 2011
Filed:
Jun. 25, 2008
Yasuhito Yamamoto, Nirasaki, JP;
Isamu Inomata, Nirasaki, JP;
Yasuhito Yamamoto, Nirasaki, JP;
Isamu Inomata, Nirasaki, JP;
Tokyo Electron Limited, Tokyo, JP;
Abstract
An inspection apparatus for inspecting electric characteristics of a plurality of devices formed on a target object includes a vertical drive mechanism for lifting and lowering a movable mounting table and a control unit for controlling the vertical drive mechanism. The vertical drive mechanism includes an elevation shaft connected to the mounting table and a servo motor for driving the elevation shaft to lift and lower the mounting table. Further, the control unit has a servo driver which includes a position control part for controlling a position of the servo motor, a torque control part for controlling a torque of the servo motor as a probe card is expanded or contracted by a change in temperature and a switching part for switching the position control part and the torque control part.