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:
May. 16, 2000
Filed:
Nov. 03, 1998
Ming-Che Yang, Kaohsiung, TW;
Kuo-Feng Huang, Hsinchu Hsien, TW;
Eric Liu, Hsinchu, TW;
En-Tien Tan, Hsinchu, TW;
United Microelectronics Corp., Hsinchu, TW;
Abstract
A photoresist dispensing system used in a photoresist coating machine includes a pump, a sucking-back valve, a solenoid valve, a first pump speed controller, a second pump speed controller and a sucking-back speed controller. The pump is used to transport photoresist and spray a substrate. The sucking-back valve is used to suck back liquid photoresist from a transporting duct end. The solenoid is used to activate or inactivate the pump and the sucking-back valve. The first and the second pump speed controllers are separately coupled between the pump and the solenoid valve, and the sucking-back speed controller is coupled between the sucking-back valve and the sucking-back speed controller is coupled between the sucking-back valve and the route, where is between the pump and the second pump speed controller. Hence, the sucking-back valve produces a sucking force after the pump is inactivated and releases a sucking force after pump is activated.