Cleaning and liquid contact with solids – Processes – Combined
Reexamination Certificate
2001-02-12
2001-09-11
Coe, Philip R. (Department: 1746)
Cleaning and liquid contact with solids
Processes
Combined
Reexamination Certificate
active
06287390
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus and method of cleaning nozzle and an apparatus of processing a substrate.
In a photolithographic process for use in manufacturing semiconductor devices, resist is coated on a wafer and the resultant wafer is pattern-exposed to light and then developed. In a developing process, a developing solution is supplied so as to spread over an entire surface of the wafer. To describe more specifically, the developing solution is mounted on a stationary wafer, and then, a latent image is developed by use of natural convection of the developing solution. After the development, the wafer is rotated at a high speed to remove the developing solution from the wafer, rinsed and dried.
As the developing solution, for example, an aqueous tetramethylammonium hydroxide (TMAH) solution is used. When the aqueous TMAH solution is attached to a tip portion of the developing nozzle, dried and oxidized, a carbonate compound is produced. The produced carbonate compound may possibly exfoliate off from the tip portion of the developing nozzle and attach to a wafer as a contaminant.
When the developing nozzle is not used for a long time or when the specs (recipe) of the process is changed, an operator manually cleans the tip portion of the developing nozzle. To render the developing nozzle ready to use after the cleaning, a trial output of the developing solution from the nozzle, called “dummy running”, is required. However, these serially performed manual operations are quite complicated and becomes a burden of the operator.
BRIEF SUMMARY OF THE INVENTION
An object of the present invention is to provide an apparatus and method of cleaning a nozzle, and an apparatus of processing a substrate, capable of simplifying the cleaning operation and reducing a cleaning frequency of a tip of the processing solution nozzle by performing the cleaning in timing set in accordance with the most suitable mode defined by a type of processing liquid and state of use.
According to the present invention, there is provided an apparatus of cleaning a nozzle comprising:
a mounting table for mounting a substrate to be processed;
a process liquid nozzle having a liquid output portion for outputting a process liquid toward the substrate mounted on the table;
a nozzle cleaning mechanism having a fluid spray portion for spraying a cleaning fluid onto the liquid output portion of the process liquid nozzle to remove an attached material from the liquid output portion by the cleaning fluid sprayed from the fluid spray portion; and
a nozzle moving mechanism for moving the process liquid nozzle between the mounting table and the nozzle cleaning mechanism.
It is further desirable that the apparatus according to the present invention comprise
means for setting a threshold which is a reference for determining whether cleaning of the liquid output portion of the process liquid nozzle is initiated or not; and
control means for controlling the cleaning of the liquid output portion of the process liquid nozzle by counting at least one selected from the group consisting of a number of processed lots, a number of processed substrates, and non-operation time during which no process liquid is output from the process liquid nozzle, comparing a count value with the threshold, and initiating the cleaning of the liquid output portion of the process liquid nozzle by the nozzle cleaning mechanism when the count value exceeds the threshold.
According to the present invention, there is provided a method of cleaning a nozzle comprising the steps of:
(a) setting a threshold of at least one mode selected from the group consisting of a number of processed lots (lot mode), a number of processed substrates (substrate mode), and non-operation time (limit timer mode) during which no process solution is output from a process liquid nozzle, the threshold being a reference in determining whether cleaning of a liquid output portion of a process liquid nozzle is initiated or not;
(b) counting at least one selected from the group consisting of the number of processed lots, the number of processed substrates, and the non-operation time during which no process solution is output form the process liquid nozzle; and
(c) initiating cleaning of the process liquid nozzle by spraying a cleaning fluid onto the process liquid nozzle when at least one selected from the group consisting of the number of processed lots (lot mode), the number of processed substrates (substrate mode), and the non-operation time (limit timer mode) during which no process solution is output from the process liquid nozzle, exceeds the threshold.
In the steps (a) to (c), either one or two modes are selected from the group consisting of the lot mode, the substrate mode, and the limit timer mode, and cleaning of the process liquid nozzle is initiated by using a mode thus selected.
In the step (c), It is preferable that the process liquid is output from the process liquid nozzle when the process liquid nozzle is cleaned.
According to the present invention, there is provided an apparatus of processing a substrate comprising:
a mounting table for mounting a substrate having a pattern-exposed photoresist film;
a developing nozzle having a liquid output portion for outputting a developing solution toward the photoresist film of the substrate on the mounting table;
a nozzle cleaning mechanism having a cleaning fluid spray portion for selectively spraying pure water and an inert gas toward the liquid output portion of the developing nozzle and removing an attached material from the liquid output portion with the pure wafer and the insert gas sprayed from the cleaning fluid spray portion; and
a nozzle moving mechanism for moving the developing nozzle between the mounting table and the nozzle cleaning mechanism.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.
REFERENCES:
patent: 4977911 (1990-12-01), Vetter et al.
patent: 5405087 (1995-04-01), Waryu et al.
patent: 5779796 (1998-07-01), Tomoeda et al.
patent: 5927305 (1999-07-01), Shiba
patent: 58830 (1988-03-01), None
patent: 8621 (1989-01-01), None
patent: 5-166715 (1993-07-01), None
Matsuo Kazutaka
Sakai Hiroyuki
Coe Philip R.
Oblon & Spivak, McClelland, Maier & Neustadt P.C.
Tokyo Electron Limited
LandOfFree
Apparatus and method of cleaning nozzle and apparatus of... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus and method of cleaning nozzle and apparatus of..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method of cleaning nozzle and apparatus of... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2498460