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, 1999
Filed:
Apr. 28, 1997
Fumihiko Uesugi, Tokyo, JP;
Natsuko Ito, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A particle monitor includes a light source for transmitting a light into a space over a wafer in wafer processing equipment to irradiate particles floating above the wafer for causing a scattered light; a photo-detector for detecting the scattered light to generate output signals corresponding to the intensity of the scattered light; a signal intensity judgment device for receiving the output signals from the photo-detector and comparing the output signals with a predetermined reference value already set in the signal intensity judgment device so as to judge whether the intensity of the scattered light is higher or lower than the predetermined reference value; and a display for displaying the intensity of the scattered light and luminance and distribution in intensity thereof or displaying distributions in size and the number of particles.