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:
Jul. 07, 1998
Filed:
Feb. 21, 1996
Tim Z Hossain, Round Rock, TX (US);
John K Lowell, Round Rock, TX (US);
Advanced Micro Devices, Inc., Sunnyvale, CA (US);
Abstract
A method and apparatus are presented which provide non-intrusive detection of atoms of light elements (atomic numbers 3-13) on a surface of a semiconductor substrate using X-ray fluorescence (XRF). The present technique may be economically performed routinely on manufactured products. The method includes producing a monochromatic X-ray beam comprising X-ray photons with energy levels operably chosen to cause only atoms of light elements to emit secondary X-ray photons. The monochromatic X-ray beam is then focused onto a circular exposed region on the surface of the semiconductor substrate, the circular exposed region having a diameter ranging from about 0.5 mm to about 10.0 mm. Secondary X-ray photons emitted by atoms of light elements in the exposed region on the surface of the semiconductor substrate are directed to at least one X-ray detector. Each X-ray detector is aligned to receive secondary X-ray photons from a single light element, and is illuminated for a predetermined amount of time. The number of secondary X-ray photons detected by an X-ray detector in a predetermined amount of time is directly proportional to the number of atoms of a corresponding light element on the surface of the semiconductor substrate. The apparatus includes a high-power X-ray source, a first collimator, a first multilayer crystal, a focusing capillary, a second collimator, a second multilayer crystal, and at least one X-ray detector.