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The main issue for developing EUV resist is to satisfy th e ITRS tar get of sensitivity, line edge roughness(LER), and resolution simultaneously . Howe ver, Resist resea rchers have dif ficulty in EUV resist development because they are tradeoff relationships each other. Among them, LER is cl osely related t o acid diffusion length of photo acid generator.Researchers have tried to accomplish uniform distribution and diffusion minimization of PAG in photoresist film in order to improve LER. They are mainly using two kinds of method for PAG introduction for uniform distribution and diffusion minimization. One i s u se of sulfonium sal ts ha ving ultra bulky ani on o r cat ion for t he aci d diffusion su ppression, t he other is direct incorporation of the PAG into the polymer backbone. In that regard, we have pursued development of a variety of 193nm and E UV CARs that contain photoacid generator(PAG) units covalently bonded directly to the resin polymer backbone. Whe n we consider pol ymer bound PAG, there can b e anionic pol ymer bound PAG resi st, cationic polymer bound PAG resist and n onionic po lymer bound resist. In this w ork, w e will d iscuss d iffusion length and lin e edge roughness(LER) of t hese polymers. Acid di ffusion l ength(Ld) an d diffusion c oefficient(D) were cal culated by according to t he m odified Fi ck,s e quation. As a result of this m easurements we kne w that diffusion l ength of general PAG use as ArF photoresist composition was ranged from thousands of nm to ten of nm and PAG diffusion length having bulky a nion a nd cat ion i s was wi thin a t en nm. In case of ani onic p olymer bo und PAG, aci d diffusion l ength showed under 10nm.Extreme Ultraviolet (EUV) Lithography II, edited by Bruno M. La Fontaine, Patrick P. Naulleau, Proc. of SPIE Vol. 7969, 79692N · © 2011 SPIE · CCC code: 0277-786X/11/$18 ·

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One of the most important factors in ArF resist development is a resin platform, which dominates a lot of parts of resist characteristics. It has been much changed in order to improve their physical properties such as resolution, pattern profile, etch resistance and line edge roughness. Through the low etch resistance in ArF initial (meth)acryl type copolymer and low transmittance in COMA type copolymer most researchers were interested in developing of (meth)acryl type copolymer again for ArF photoresist. On the other hand, we have studied various polymer platforms suitable ArF photoresist except for meth(acryl) type copolymer. As a result of this study we had developed ROMA type polymers and cycloolefin-(meth)acryl type copolymers. Among the polymers cycloolefin-(meth)acryl type copolymer has many attractions such as etch roughness, resist reflow which needs low glass transition temperature and solvent solubility. In this study, we intend to find out cycloolefin-(meth)acryl copolymer characteristics compared with (meth)acryl copolymer. And, we have tried to find out any differences between acrylate type copolymer and cycloolefin-(meth)acrylate type copolymer with various evaluation results. As a result of this study we are going to talk about the reason that the resist using acrylate type copolymer and cycloolefin-(meth)acryl type copolymer show good pattern profile while acrylate type copolymer show poor pattern profile. We also intend to explain the role of cycloolefin as a function of molecular weight variation and substitution ratio variation of cycloolefin in cycloolefin-(meth)acrylate resin.