A novel noria (water-wheel-like cyclic oligomer) derivative as a chemically amplified electron-beam resist material

Microelectronic Engineering

Kozawa

2015

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Novel resist materials are required for lithographic processing with ionization radiation such as extreme ultraviolet (EUV) and electron beam (EB) exposure tools. In this study, we synthesized positive-tone chemically amplified molecular resist materials with pendant adamantyl ester (AD) and cyclohexyl 2-propyl ether moieties based on cyclic oligomers such as noria, calixarene dimer, cyclodextrin, and pillar [5]arene, and we examined the lithographic performances of sensitivity, etching durability, and patterning under EUV and EB exposure. We clarified that the sensitivity of the resist materials was consistent with the structure of the cyclic oligomers, i.e., the hole size of the molecular structure might be an important factor relevant to high-resolution resist materials. We found that chemically amplified molecular resists based on cyclic oligomers such as noria, calixarene dimer, cyclodextrin, and pillar [5]arene are promising candidates for higher-resolution resist materials.Corresponding Author

Section: Introductionmentioning

confidence: 99%

Study on resist performance of chemically amplified molecular resists based on cyclic oligomers

Yamamoto

Microelectronic Engineering

Kozawa

2015

Self Cite

“…17 The structure of Noria-OEt was confirmed by 1 H nuclear magnetic resonance, Fourier-transform infrared and matrix-assisted laser desorption ionization time-of-flight mass analysis. The molecular weight (M n ) and distribution of molecular weight (M w /M n ) were estimated by SEC analysis.…”

Section: Resultsmentioning

confidence: 97%

“…16,17 A Noria derivative with adamantane groups (Noria-Ad) showed resolution patterns of 26-nm hp, with a dose of 14.5 mJ cm À2 as a positively working EUV resist. 18,19 A Noria derivative with oxcetanyl groups (Noria-GOx) was also synthesized as a negatively working photoresist using the cationic polymerization of oxcetane.…”

Section: Introductionmentioning

confidence: 99%

Multicomponent negative-type photoresist based on Noria analog with 12 ethoxy groups

Niina

Maruyama³

et al. 2011

Polym J

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The characteristics of Noria analogs with 12 ethoxy groups and 12 hydroxy groups (Noria-OEt), which were synthesized by the condensation reaction of 3-ethoxyphenol with 1,5-pentanedial, were examined in detail. The solubility of the synthesized Noria-OEt in common organic solvents was better than that of Noria. In addition, Noria-OEt was soluble in 2.38 wt% tetrametyl ammonium hydroxide (TMAH) aqueous as a developer. The thermal stability and mechanical properties were similar to those of Noria because of the ladder structure and amorphous characteristics, which means that the film-forming properties were confirmed. These characteristics are advantageous for use as a molecular glass photoresist. The patterning properties of the negative-type, alkaline developable, multicomponent photoresist based on Noria-OEt, with polyfunctional benzyl alcohols as a crosslinker and a photoacid generator, were evaluated with an extreme ultraviolet lithography system. This negative-type photoresist with 2,4-dihydroxymethyl-6-methylphenol as a crosslinker gave a resolution pattern of 35 nm half-pitch with 10.0 mJ cm À2 .

“…Recently, Kudo and coworkers have succeeded in the synthesis of a new ladder cyclic oligomer "noria" (water wheel in Latin) [13] and reported the synthesis and photochemical reactivity of noria derivatives containing t-butoxycarbonyl groups [14,15], t-butylester groups [16], acetal groups [17,18], and adamantyl ester groups [19][20][21][22][23]. It was found that these noria derivatives have high photoreactivity and produce clear line and space patterns with resolutions of 50-70 nm using an EB exposure tool and 26 nm using an EUV exposure tool [15][16][17][18][19][20][21][22][23]. Moreover, we clarified that the sensitivity of the resist materials was consistent with the structure of the cyclic oligomers such as noria, calixarene dimer, cyclodextrin, and pillar [5]arene [24].…”

Section: Introductionmentioning

confidence: 99%

Study on Resist Performance of Noria Derivatives Modified with Various Protection Ratios of Acetal Moieties by means of Extreme Ultraviolet Irradiation

Yamamoto

J. Photopol. Sci. Technol.

Kozawa

2017

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The requirements for next generation resist materials in extreme ultraviolet (EUV) lithography are very challenging. Therefore, the development of new resist materials has been expected to meet strict requirements. Molecular resists are promising resists owing to the small size of their building blocks. In this study, we examined lithographic performances, such as sensitivity and patterning, using noria derivative (noria-CHVEs, Resists 1-3) under EUV and a 75 keV electron beam (EB) exposure system. In particular, the effect of the protection ratio on the lithographic performances was studied by changing the protection ratio. The sensitivities of noria-CHVEs showed high values in the range between 1.8 and 3.0 mJ/cm 2 . Resist 2 could provide a resist pattern with a higher resolution than Resists 1 and Resist 3, i.e., a semi-isolated pattern with a line width of 30 nm (pitch: 100 nm). These results indicate that the synthesized noria-CHVEs are promising EUV resist materials.