1,3,5-Tris(4-(tert-Butoxycarbonylmethoxy)-phenyl)benzene as a Novel Electron-beam Positive Resist for Nanometer Lithography.

Abstract

The minimum feature size in semiconductor devices is becoming smaller and smaller. A 0.35 µm resolution is required for the fabrication of 64 Mbit DRAM, and nanometer-size lithographic patterns will be required in the future. One of the factors determining the resolution limit of the lithography process is the particle size of resist materials. In order to obtain nanometer-size lithographic patterns, it is desirable to reduce particle size of the resist materials. Organic polymers have been used as resist materials. The particle size of organic polymers with a degree of polymerization of 105 is roughly calculated to be 10 nm [1]. This means that there is more than 10 % fluctuation in 100 nm lithographic patterns. A breakthrough to achieve nanometer-size lithography is to develop lowmolecular-weight organic resist materials. However, low-molecular-weight organic compounds generally do not form uniform stable amorphous films, since they tend to crystallize readily. Very recently, an oligomer, a calixarene derivative [2], and a vacuum evaporated film of C60 [3] have been reported to function as negative electron-beam resists with high resolution.We report here a novel low-molecular-weight organic compound, 1,3,5-tris[4-(tert-butoxycarbonylmethoxy)phenyl]benzene(BCMTPB), which functions as a positive-type electron-beam resist material. The new compound BCMTPB was synthesized by the condensation reaction of 1,3,5-tris(4-hydroxyphenyl)benzene with chloroacetic acid tert-butyl ester and identified by various spectroscopies, mass spectrometry and elemental analysis.BCMTPB was found to form readily an amorphous glass, as evidenced by differential scanning calorimetry. When the crystalline sample of BCMTPB obtained by recrystallization from benzene/hexane was heated, an endothermic peak due to melting was observed at 141 °C. When the resulting isotropic liquid was cooled on standing in air, it formed an amorphous glass via a supercooled liquid. When the amorphous

Amorphous Molecular Materials. Development of a Novel Positive Electron-beam Molecular Resist.

“…150 nm and 70 nm, respectively. [4][5][6] Related to our studies, an oligomer of a calixarene derivative has also been reported to function as a negative electron-beam resist with high resolution. [7] We report here the creation of a novel molecular resist material, 1,3,5-tris[4-(2-tent-butoxycarbonyloxy) phenyl] benzene (o-BCOTPB).…”

A Novel Low Molecular-Weight Organic Resist with High Sensitivity for Nanometer Lithography.

“…150 nm and 70 nm, respectively. [ 1,2] An oligomer of a calixarene derivative has also been reported to function as a negative electron-beam resist with high resolution. [3] We report here a novel molecular resist material, 1,3,5-tris[4-(4-vinylphenylcarbonyloxy)phenyl]benzene (VCTPB).…”

Extreme Ultraviolet (EUV)-Resist Material Based on Noria (Water Wheel-like Macrocycle ) Derivatives with Pendant Alkoxyl and Adamantyl Ester Groups

“…However, there is a serious problem among the resolution of pattern, sensitivity of the photo-chemical reaction, and roughness of the pattern, i.e., these relationships are well known as "trade-off". To overcome this "trade-off", many molecular glasses such as calixarenes, 1-10 dendritic oligomers, [11][12][13][14][15][16][17][18] low-molecular-weight oligomers, 19,20 and fullerenes 21 have been reported and their resolutions showed about 50 nm regions. Recently, we could design a ladder type cyclic oligomer "noria" (noria = water wheel in Latin), 22 and examined the synthesis, physical properties, and patterning properties of noria derivatives with pendant t-butyl ester groups, 23,24 t-butyloxycarbonyl groups, 25 adamantyl ester groups, 26,27 cyclohexyl acetal moiety, 28 and oxetanyl groups 29 using electron beam (EB) or EUV exposure systems.…”