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:
Jan. 12, 1999
Filed:
Sep. 04, 1996
Ayumi Suda, Chigasaki, JP;
Yoshinobu Hiraishi, Omura, JP;
Komatsu Electronic Metals Co., Ltd., Hiratsuka, JP;
Abstract
The objects of the present invention are to remove the dust in a closed container, to keep the pressure in the closed container within a predetermined range, and to shorten the maintenance time of a vacuum pump system. The present invention provides a centrifugal dust collector 2 on main pipes which connects a furnace body 1, a mechanical press 9 and a dry pump 10, and a metal mesh dust collector 15 on a bifurcated pipe in a single-crystal semiconductor pulling apparatus. When the vacuum pump process begins, the metal mesh dust collector 15 collects amorphous silicon generated in the furnace 1. As the pressure in the furnace is reduced, the centrifugal dust collector 2 collects the dust particles instead. Since the gas flow rate increases as the vacuum state become higher, the critical diameter of collectable particles decreases, thereby improving the dust collection efficiency. The collected amorphous silicon accumulates on the bottom of the centrifugal dust collector and can be easily removed so as to facilitate maintenance. Moreover, there will be very little pressure variance in the furnace since no dust filter is blocked.