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:
Mar. 01, 1994
Filed:
Nov. 30, 1992
Michael D Smith, Austin, TX (US);
Advanced Micro Devices, Inc., Sunnyvale, CA (US);
Abstract
An apparatus is disclosed for automatic optical inspection of a wafer boat having a plurality of parallel slotted side rods and bottom rods. A cradle holds the wafer boat in a stationary position. A separate optical sensor is mounted upon a carriage for each of the rods to be measured. Each of these sensors projects an optical beam toward the corresponding rod where, when longitudinally aligned within an individual slot, the beam is parallel to and substantially near the bottom of the slot. As the carriage is scanned from one end of the rods of the wafer boat to the other, the optical beam will be alternately obstructed by the rod or transmitted through a slot, thereby determining the slot edge locations of each of the slots in each of the rods in accordance with the position of the carriage. The slot widths and slot locations can then be determined from the slot edge locations. Additionally, the length of each of the bottom rods can be measured by reflecting an optical beam off of a flat surface of a clamp block positioned against the end of each of the bottom rods.