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:
Sep. 24, 2002
Filed:
Jul. 03, 2000
Rahul V. Gune, Pakkred Nonthaburi, TH;
Watcharin Pinlam, Pathumthanee, TH;
Advanced Micro Device, Inc., Sunnyvale, CA (US);
Abstract
Unacceptable warpage of a tray for holding a plurality of integrated circuit packages is automatically detected after an operator places the tray on a conveyor. The conveyor holds and moves the tray along a predetermined linear path, and the predetermined linear path is along a length of the tray. Each of a plurality of tray position sensors is disposed at a respective location along the predetermined linear. path, and each tray position sensor detects when an object that moves with the conveyor, such as a bracket that is connected to the conveyor, has reached the respective location along the predetermined linear path. A laser beam source is disposed on a first side of the predetermined path for generating a laser beam toward a first side of the tray, and the laser beam has a field that extends through any possible height of the tray. A laser beam sensor is disposed on a second side of the predetermined path and faces toward a second side of the tray that is opposite the first side of the tray such that the laser beam sensor detects a portion of the laser beam that is not blocked by the tray. A data processor controls the conveyor to move the tray along the predetermined path. When the object that moves with the conveyor reaches a tray position sensor, the data processor controls the conveyor to stop movement of the tray such that a measured height of the tray at a measured location of the tray is determined from the portion of the laser beam that is not blocked by the tray at the measured location of the tray as detected by the laser beam sensor. The tray is determined to be unacceptably warped when the measured height is greater than a predetermined value.