Organic anti-reflective coating polymers, anti-reflective coating composition comprising the same and preparation methods thereof

Abstract

An organic anti-reflective polymer which prevents back reflection of lower film layers and eliminates standing wave that is occurred by a thickness change of photoresist and light, in a process for fabricating ultrafine patterns that use photoresist for lithography by using 193 nm ArF and its preparation method. More particularly, the organic anti-reflective polymer of the present invention is useful for fabricating ultrafine patterns of 64M, 256M, 1G, and 4G DRAM semiconductor devices. A composition containing such organic anti-reflective polymer, an anti-reflective coating layer made therefrom and a preparation method thereof.

Description

BACKGROUND[0001] 1. Technical Field[0002] An organic anti-reflective polymer which prevents back reflection of lower film layers and eliminates standing wave that occurs as a result of thickness changes of photoresist and light, in a process for fabricating ultrafine patterns that use photoresist for lithography by using 193 nm ArF and its preparation method are disclosed. More particularly, the organic anti-reflective polymer is disclosed that is useful for fabricating ultrafine patterns of 64M, 256M, 1G, and 4G DRAM semiconductor devices. A composition containing such organic anti-reflective polymer, an anti-reflective coating layer made therefrom and a preparation method thereof are also disclosed.[0003] 2. Description of the Background Art[0004] In a fabrication process of ultrafine patterns for preparing semiconductor devices, standing waves and reflective notching inevitably occur due to the optical properties of lower film layer on the wafer and due to the thickness change of...

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Benefits of technology

[0046] Further, the anti-reflective coating resin dissolves well in all hydrocarbon solvent, while does not dissolve in any of the solvents during a hard-baking step and it does not experience undercutting and footing in a fabrication process of patterns. Particularly, because the anti-reflective coating resin is composed of acrylate polymer, its etching speed is higher than that of a photosensitive film and thus, the etching selectivity can be improved.

[0047] The present invention has been described in an illustrative manner, and it is to be understood the terminology used is intended to be in the nature of description rather than of limitation. It must be understood that many modifications and variations of the present invention are possible in light of the above teachings. Therefore, it is to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

Problems solved by technology

In a fabrication process of ultrafine patterns for preparing semiconductor devices, standing waves and reflective notching inevitably occur due to the optical properties of lower film layer on the wafer and due to the thickness change of photosensitive film.

In addition, there is another problem of the CD (critical dimension) alteration caused by diffracted and reflected light from the lower film layers.

However, in the case of an inorganic anti-reflective film, no material has been known which enables the control of the interference at 193 nm, the wavelength of light source.

But these two types of anti-reflective material have a problem in that the control of k value is almost impossible because the content of the chromophore is defined according to the ratio as originally designed at the time of polymerization.

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