Cleaning and liquid contact with solids – Processes – Including application of electrical radiant or wave energy...
Reexamination Certificate
1998-07-28
2001-01-30
Markoff, Alexander (Department: 1746)
Cleaning and liquid contact with solids
Processes
Including application of electrical radiant or wave energy...
C134S018000, C134S036000, C134S102100, C134S102300
Reexamination Certificate
active
06178973
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention generally relates to the treatment of a substrate surface. Surface treatment, for example oxidizing, cleaning, or planarizing a substrate surface, is a critical operation, especially in the semiconductor industry, where irregularities within a surface or foreign contaminants on the surface can cause device failure. The sensitivity to foreign matter on the surface and to irregularities within the surface is increased as device sizes shrink in the semiconductor industry. Foreign matter as small as sub-micron particles can destroy a semiconductor integrated circuit. Furthermore, when a surface treatment is being carried out, it is desirable that the treatment does not otherwise damage the substrate surface being treated.
An example of foreign matter which commonly must be removed from a surface in the semiconductor industry is organic material. Photoresist is an example of an organic material frequently used in the semiconductor processing industry. After a photoresist film has been used to create a mask on a semiconductor surface being processed, it is generally necessary that the photoresist film be completely removed before subsequent fabrication processes may be carried out. The complete removal of the photoresist film is made more difficult when the photoresist film becomes hardened on the substrate surface. Hardening of the photoresist film occurs when the photoresist film is exposed to a plasma environment or ion implantation, two common fabrication processes. Incompletely removed photoresist can cause device failures.
It is commonly known that organic contaminants may be removed by ultraviolet (uv) cleaning. Ultraviolet light, which is defined by the wavelength range of 4 nm to 380 nm, has been known to decompose organic molecules. Another method known in the art which is useful for removing or assisting in the removal of unwanted organic material is the chemical oxidation of these organics.
Processes and apparatus for using uv light to decompose organic molecules and treat a substrate surface are known in the related art. The related art also provides a method for the generation of ozone for use in surface treatment. The production of ozone from high voltage discharges between metal electrodes, however, frequently produces metal ion contaminants unsuitable for the semiconductor processing industry. A further shortcoming of the prior art is that separate sources of energy are required for ozone production and uv light surface treatment.
SUMMARY OF THE INVENTION
The present invention embodies both the method and apparatus for the treatment of a substrate surface, by generating ozone, utilizing the ozone for surface treatment and using a light energy source for additionally treating the substrate surface. The invention includes at least one optical source having an optical path. The light energy source used for surface treatment in the treatment chamber may be the same light energy source used to generate ozone in a separate generation chamber.
The present invention includes at least two distinct chambers: An ozone generation chamber containing oxygen and disposed along the optical path of the optical source; and a surface treatment chamber. Ozone generation and surface treatment may occur simultaneously. The chambers may be separated by a quartz plate to provide for a single optical source to be used for the simultaneous surface treatment in the treatment chamber and ozone generation in the generation chamber. The surface treatment of the present invention may involve oxidation, cleaning, planarization, or a combination of the three.
The generation chamber includes optical condensing means which function as a collimator to focus the optical energy source into a focal point where ozone is generated. Ozone produced in this manner is free of the undesirable metal ion contaiminants associated with ozone generation between metal electrodes using high voltage.
The generated ozone is withdrawn from the generation chamber and transported to the treatment chamber to chemically assist in the surface treatment. The ozone gas may be mixed with another constituent prior to its introduction into the treatment chamber, or the ozone and constituent may be intermixed with each other once both have been transported to the treatment chamber. The other component may be a gas, a liquid, or a liquid which has been heated by the ozone to form a vapor.
Within the treatment chamber, the gases or components may be delivered to the surface of the substrate or they may be delivered into the chamber at a location remote from the surface to be treated. The treatment chamber contains a substrate with matter on the surface, as well as a substrate holder. This holder may also include a chilling plate or a heating element.
The present invention is directed to both the process for generating ozone and for performing the surface treatment detailed above, and also the multi-chamber apparatus for carrying out this treatment.
REFERENCES:
patent: 4252623 (1981-02-01), Vaseen
patent: 4292093 (1981-09-01), Ownby et al.
patent: 5024968 (1991-06-01), Engelsberg
patent: 5304352 (1994-04-01), Bellettini et al.
patent: 5503708 (1996-04-01), Koizumi et al.
patent: 5580421 (1996-12-01), Hiatt et al.
patent: 5643367 (1997-07-01), Viel
patent: 5669979 (1997-09-01), Elliott et al.
patent: 5709754 (1998-01-01), Morinville et al.
patent: 5729343 (1998-03-01), Aiyer
Handbook of Semiconductor Wafer Cleaning Technology, Noyes Publications. pp. 201-273, 1993.
Franca Daniel L.
Ouimet, Jr. George F.
Ziemins Uldis A.
International Business Machines - Corporation
Markoff Alexander
Ratner & Prestia
LandOfFree
Method and apparatus for ozone generation and surface treatment does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for ozone generation and surface treatment, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for ozone generation and surface treatment will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2462841