Spin coating apparatus
First Claim
1. An apparatus for spin-coating a flat object with a viscous coating liquid, comprising:
- (a) dispenser means having a diaphragm pump for sucking the coating liquid from a liquid source and for discharging and dropping the sucked liquid in a constant amount and at a constant speed from a discharge nozzle onto the flat object placed on a rotary stage;
(b) a dispenser central control device including a microcomputer or minicomputer for controlling said diaphragm pump; and
(c) diaphragm displacement detection means for detecting at least one of a position and displacement speed of a diaphragm of said diaphragm pump in a noncontacting manner, and for delivering data of the at least one of the position and displacement speed to said central control device.
1 Assignment
0 Petitions
Accused Products
Abstract
The present invention relates to a spin coating apparatus for feeding a clean liquid at a fixed rate. In any of the feeding apparatus in the prior art, no constituent other than a filter has the function of eliminating foreign matter, and the operation of feeding a liquid under precise control is not attained. This results in the problem of the mixing of the foreign matter (and air bubbles) in the feed liquid, and the problem of nonuniformity in a feed speed as well as a feed amount. As expedients for solving these problems, the present invention provides the functions of automatically sensing and excluding factors for the appearances of the foreign matters, and devices for automatically and precisely controlling feed control elements such as a pump, thereby feeding the clean liquid in a constant amount and at a constant speed.
134 Citations
23 Claims
-
1. An apparatus for spin-coating a flat object with a viscous coating liquid, comprising:
-
(a) dispenser means having a diaphragm pump for sucking the coating liquid from a liquid source and for discharging and dropping the sucked liquid in a constant amount and at a constant speed from a discharge nozzle onto the flat object placed on a rotary stage; (b) a dispenser central control device including a microcomputer or minicomputer for controlling said diaphragm pump; and (c) diaphragm displacement detection means for detecting at least one of a position and displacement speed of a diaphragm of said diaphragm pump in a noncontacting manner, and for delivering data of the at least one of the position and displacement speed to said central control device. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
-
-
16. An apparatus for spin-coating a flat object with a viscous liquid comprising:
-
(a) dispenser means having suck-back means including a diaphragm pump by which, in sucking the coating liquid from a liquid source and then dropping the coating liquid from a discharge nozzle onto the flat object placed on a rotary stage, the coating liquid within said discharge nozzle is sucked inwardly of said nozzle in a constant amount and at a constant speed after each preceding drop in order to prevent any undesirable drop; (b) a dispenser central control device including a microcomputer and minicomputer for controlling said suck-back means; and (c) diaphragm displacement detection means for detecting at least one of a position and displacement speed of a diaphragm of said diaphragm pump of said suck-back means in a noncontacting manner, and for delivering data of at least one of the position and displacement speed to said central control device. - View Dependent Claims (17, 18, 19, 20, 21, 22)
-
-
23. An apparatus for spin-coating a flat object with a viscous coating liquid, comprising:
-
(a) dispenser means having a diaphragm pump for sucking the coating liquid from a liquid source and for discharging and dropping the sucked liquid in a constant amount and at a constant speed from a discharge nozzle onto the flat object placed on a rotary stage; and (b) a dispenser central control device including a microcomputer or minicomputer for controlling said diaphragm pump; (c) diaphragm displacement detection means for detecting at least one of a position and displacement speed of a diaphragm of said diaphragm pump in a noncontacting manner, and for delivering data of the at least one of the position and displacement speed to said central control device; (d) viscosity measurement means for measuring a viscosity of said coating liquid, and for delivering data of the viscosity to said central control device; (e) foreign matter detection means for detecting foreign matter contained in said coating liquid within said dispenser means, and for delivering data of the foreign matter to said central control device; (f) said diaphragm pump having a coating liquid suction valve or discharge valve provided independently of a diaphragm drive section, said diaphragm drive further includes a liquid pressure feed chamber and a pressure chamber; (g) filter means interposed between said diaphragm pump and said suction or discharge valve, for removing foreign matter contained in said coating liquid; (h) feed pressure detection means for detecting a pressure of said pressure feed chamber of said diaphragm pump; wherein said central control device calculates an optimum feed pressure from the diaphragm displacement data and data of the feed pressure so as to control the feed pressure; (i) valve or diaphragm damage detection means for detecting damage of a valve or diaphragm provided in said dispenser means, and for delivering data of the damage to said central control device; and (j) gas bubble trap means provided in said dispenser means, for trapping gas bubbles contained in said coating liquid.
-
Specification