Radiation imagery chemistry: process – composition – or product th – Imaging affecting physical property of radiation sensitive... – Forming nonplanar surface
Reexamination Certificate
1999-10-19
2001-09-04
Ashton, Rosemary E. (Department: 1752)
Radiation imagery chemistry: process, composition, or product th
Imaging affecting physical property of radiation sensitive...
Forming nonplanar surface
C430S311000, C430S320000, C430S326000, C430S330000
Reexamination Certificate
active
06284438
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method for manufacturing a semiconductor device, and more particularly, to a method for manufacturing a photoresist pattern defining an opening having a small critical dimension. The invention also relates to a semiconductor device prepared by the aforementioned method.
2. Description of the Related Art
Semiconductor manufacturing processes have become more complicated, and the integration degree of a semiconductor chip has increased to more than 1 Giga bit DRAM. It has therefore become necessary to form minute patterns according to a design rule of less than 0.25 &mgr;m. These minute patterns have recently been formed using a deep-UV (248 nm) light, which has a shorter wavelength than conventional g-line (436 nm) and i-line (365 nm) light, as a light source in the semiconductor manufacturing processes. In addition, half-tone phase shift masks now are being used as the photomask in semiconductor manufacturing processes instead of the conventional light-shielding pattern masks, such as binary chrome masks. The conventional light sources having longer wavelengths (e.g., g-line or i-line) or photoresist materials that are used for the binary chrome mask typically exhibit a low contrast when they are used in a photolithography process, which uses the deep-UV light source and the half-tone phase shift mask. It has therefore not been heretofore possible to form a photoresist pattern defining an opening having a small critical dimension (i.e., small size) to have a desired profile.
In another method for forming a minute pattern, the size of the opening defined by the photoresist pattern can be reduced by thermally flowing the photoresist pattern after forming it. In this thermal flowing method, care should be taken to minimize the variation of the critical dimension (i.e., size, diameter, circumference, etc.) of the photoresist pattern according to changes in temperature. In particular, care should be taken to minimize the variation of the critical dimension due to differences of flow rates according to the shape and position of the opening. Accordingly, photoresists suitable for use in this thermal flowing method are those whose flow rate, i.e., flow amount per unit temperature (nm/° C.), is small such that the flow rate can be easily controlled. Conventional photoresists, however, exhibit a high flow rate (nm/° C.) so that controlling the flow rate of the photoresist is difficult.
SUMMARY OF THE INVENTION
It is a feature of the present invention to provide a method for manufacturing a photoresist pattern defining an opening having a small size using a photoresist component having a large contrast and whose flow rate is easily controlled. It is another feature of the present invention to provide a method for manufacturing a highly integrated semiconductor device using the above method for manufacturing the photoresist pattern.
In accordance with these and other features of the invention, there is provided a method for manufacturing a photoresist pattern including:
providing a semiconductor substrate;
forming a material film to be patterned on the semiconductor substrate;
forming a photoresist film on the material film by coating thereon a photoresist composition including: (i) either a polymer mixture I containing a polymer A in which an acid-labile di-alkyl malonate group is pendant to the polymer backbone, and a polymer B in which a group that thermally decomposes at a temperature lower than the glass transition temperature of the polymer B itself is pendant to the polymer backbone, or a polymer mixture II containing the polymer B and a polymer C including acid-labile (meth)acrylate as a monomer; and (ii) a photosensitive acid generator;
forming a photoresist pattern defining an opening by patterning the photoresist film; and
reducing the size of the opening performing a thermal flow process on the photoresist pattern.
In accordance with an additional feature of the present invention, there is provided a method for manufacturing a semiconductor device having a contact hole or a damascene area of a small critical dimension (e.g., small size) by patterning an underlayer using the photoresist pattern manufactured by the above-mentioned method for manufacturing the photoresist pattern. The method for manufacturing the semiconductor device encompasses:
providing a semiconductor substrate;
forming a material film to be patterned on the semiconductor substrate;
forming a photoresist film on the material film by coating thereon a photoresist composition comprising: (i) either a polymer mixture I containing a polymer A in which an acid-labile di-alkyl malonate group is pendant to the polymer backbone and a polymer B in which a group that thermally decomposes at a temperature lower than the glass transition temperature of the polymer B itself is pendant to the polymer backbone, or a polymer mixture II containing the polymer B and a polymer C including acid-labile (meth)acrylate as a monomer; and (ii) a photosensitive acid generator;
forming a photoresist pattern defining an opening by patterning the photoresist film;
reducing the size of the opening by performing a first thermal flow process on the photoresist pattern; and
etching the material film using the photoresist pattern as a mask to form either a contact hole or a damascene in the material film, whereby the contact hole or the damascene area have the size of the opening in the photoresist pattern.
In accordance with another feature of the invention, there is provided a semiconductor device having a contact hole or a damascene area prepared by the above-mentioned method.
According to the present invention, it is possible to easily form a photoresist pattern defining an opening having a small size. It is possible to form a contact hole or a damascene area having a small size using the photoresist pattern. Therefore, it is possible to increase the degree of integration of the semiconductor device.
REFERENCES:
patent: 4842992 (1989-06-01), Arai
patent: 5856411 (1999-01-01), Choi et al.
patent: 6045970 (2000-04-01), Choi
patent: 825492 (1998-02-01), None
“The Annealing Concept for Environmental Stabilization of Chemical Amplification Resists” Ito, H. et al, in Microelectronics Technology ACS Sym. Series 614, 1995, 21-34.
Choi Sang-jun
Kang Yool
Lee Si-hyeung
Moon Joo-tae
Ashton Rosemary E.
Samsung Electronics Co,. Ltd.
The Law Offices of Eugene M. Lee P.L.L.C.
LandOfFree
Method for manufacturing a photoresist pattern defining a... 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 for manufacturing a photoresist pattern defining a..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for manufacturing a photoresist pattern defining a... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2507612