Resist composition for electron beam, EUV or X-ray

#The present invention relates to a resist composition suitable for use in an ultra-micro lithographic process, for example, the production of VLSI and high-capacity microchips, and other photofabrication processes. More specifically, the present invention relates to a positive resist composition and negative resist composition capable of forming high precision patterns using an electron beam, EUV or an X-ray.

#In integrated circuits, the degree of integration has more and more increased and in the production of a semiconductor substrate such as VLSI, processing of super-fine patterns composed of line width having a half-micron or less has been required. In order to satisfy such a requirement, the wavelength of an exposure apparatus used for a photolithography has more and more shortened and at present, the use of a far ultraviolet light and an excimer laser (e.g., XeCl, KrF or ArF) is investigated. Furthermore, the formation of finer patterns by an electron beam or an X-ray has been investigated.

#The electron beam lithography is regarded as the next generation pattern formation technique or the pattern formation technique after the next generation, and the development of a positive resist and negative resist having high sensitivity, high resolution and a rectangular profile forming property has been strongly desired.

#Measurement of Reduction Potential

#The reduction potential of acid generator was measured by a cyclic voltammetry method. Specifically, each of the acid generators shown in Table 1 below was dissolved in distilled acetonitrile under argon atmosphere to prepare a 1 mM solution of the acid generator for the measurement. A 0.1 mM solution of tetrabutylammonium perchlorate was used as a supporting electrolyte. With respect to electrodes, MP-2 (manufactured by Yanaco LID Co., Ltd.), C-2U (manufactured by Yanaco LID Co., Ltd.) and Ag/AgCl were used as a working electrode, a counter electrode and a reference electrode, respectively. The measurement was conducted at 23.5° C. The scanning speed was 50 mV/cm2. Since the acid generator was decomposed by reduction and the reaction was irreversible, only a reduction peak was observed. 1 TABLE 1 Reduction Potential Chemical Structure (vs SCE) 104 −1.14 V 105 −0.78 V 106 −0.61 V 107 −0.74 V 108 −0.68 V 109 −0.77 V 110 −0.64 V

#(1) Synthesis of Compound of (A1)