Radiation imagery chemistry: process – composition – or product th – Imaging affecting physical property of radiation sensitive... – Radiation sensitive composition or product or process of making
Patent
1997-04-11
2000-01-04
Hamilton, Cynthia
Radiation imagery chemistry: process, composition, or product th
Imaging affecting physical property of radiation sensitive...
Radiation sensitive composition or product or process of making
4302861, 4302871, 4302881, 4302811, G03F 7039, G03F 7004
Patent
active
060108266
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to resist compositions suitable for use in minute processing of semiconductor elements, and more particularly to resist materials permitting formation of patterns by irradiation of far ultraviolet radiation, krypton fluoride laser beam, electron beam or the like.
BACKGROUND ART
Upon fabrication of a semiconductor device, an image is obtained by a lithography technique in which a resist is applied to the surface of a silicon wafer to form a photosensitive film, the film is exposed to light to form a latent image, and the latent image is then developed to form a negative or positive image.
With the advancement of high integration, high density assembly, miniaturization and speedup of semiconductors toward IC, LSI and further VLSI, demands on minute processing of elements are enhanced, and there is a demand for development of techniques forming a minute pattern having a line width of 0.5 .mu.m or less at present. It is however extremely difficult to form such a minute pattern by the conventional lithography technique making use of near ultraviolet radiation or visible radiation. Its yield is also lowered to a significant extent.
Therefore, in order to enhance the resolution of exposure, there are studied other lithography techniques making use of far ultraviolet radiation (short wavelength ultraviolet radiation), krypton fluoride laser (hereinafter referred to as "KrF excimer laser") beam or the like, which is shorter in wavelength than near ultraviolet radiation, instead of the conventional lithography technique utilizing near ultraviolet rays having a wavelength of 350-450 nm.
Novolak resins are widely used as base polymers in the conventional lithography technique utilizing near ultraviolet radiation. However, the novolak resins have been known to involve problems that sufficient sensitivity can not be achieved, and the form of the resulting pattern is deteriorated because they scarcely transmit rays having a short wavelength, such as far ultraviolet radiation and KrF excimer laser.
In recent years, therefore, attention has been attracted to a resist system in which a compound (i.e., a photo-induced acid generator) which generates an acid upon exposure to active rays (i.e., activated radiation) such as light or electron beam is combined with a compound which is decomposed by an acid catalyst to become soluble in a developer with a view toward achieving high sensitivity and high resolution. For example, acetal compounds (Japanese Patent Application Laid-Open No. 89003/1973), enol ether compounds (Japanese Patent Application Laid-Open No. 12995/1980) and the like have been proposed as acid-sensitive compounds used in combination with the photo-induced acid generator. Besides, a resist composition for minute processing, which is composed of a three component system of a base polymer, a photo-induced acid generator and a substance (an acid-sensitive compound) which reacts in the presence of an acid as a catalyst, which has been generated by the exposure to light, to change the solubility and the like of the base polymer, has been developed. It has been proposed to use, as the base polymer (a resin binder), a polymer having an orthoester group in its main chain (Japanese Patent Application Laid-Open No. 17345/1981), a polymer having a tert-butyl ester group of a carboxylic acid or a tert-butyl carbonate group of phenol (Japanese Patent Application Laid-Open No. 27660/1990), or the like. However, these methods are still insufficient from the viewpoints of sensitivity, storage stability, stability with time, resolution, pattern form and the like and hence fail to provide a fully satisfactory resist composition.
It has been proposed to use a hydrogenated polyvinylphenol derivative as a base polymer for the purpose of enhancing transmittance (Japanese Patent Application Laid-Open No. 249673/1993). According to this method, resolution is improved to some extent. In view of a recent higher standard of performance requirements on resists, however, further improvements
REFERENCES:
patent: 3556793 (1971-01-01), Field et al.
patent: 3779778 (1973-12-01), Smith et al.
patent: 4248957 (1981-02-01), Sander et al.
patent: 4311782 (1982-01-01), Buhr et al.
patent: 4318976 (1982-03-01), Shu et al.
patent: 4491628 (1985-01-01), Ito et al.
patent: 4581401 (1986-04-01), Asmussen et al.
patent: 4804612 (1989-02-01), Asaumi et al.
patent: 5070001 (1991-12-01), Stahlhofen
patent: 5153095 (1992-10-01), Kawamura et al.
Derwent WPI Abstract No. XP-002064830, AN 93-185601 of Japanese Reference No. 5-113667 dated May 7, 1993.
Padwa et al, Chemical Abstracts, 100:67606 of J. Org Chem (1984), 49(3), 399-406.
Abe Nobunori
Matsuno Shugo
Sugimoto Tatsuya
Tanaka Hideyuki
Wada Yasumasa
Hamilton Cynthia
Nippon Zeon Co. Ltd.
LandOfFree
Resist composition does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Resist composition, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Resist composition will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1071349