In extreme ultraviolet lithography (EUVL), it is required to develop EUV resist which has low line width roughness (LWR) for the further miniaturization of circuit pattern. In order to reduce LWR, it is necessary to analyze and control the chemical-components spatial distribution in the resist thin film. We have reported that the measurement of chemical-components spatial distribution in the resist thin film coated on the Si₃N₄ membrane using the method of the transmission-mode resonant soft X-ray scattering (RSoXS). In this study, in order to analyze the chemical-structure-size distribution in the resist thin film on a Si wafer under similar condition adapted to the resist-coating actual process, we examined the grazing-incidence RSoXS (GI-RSoXS). A chemically amplified resist (CAR) and a non-CAR were spin-coated on silicon wafers, which had varied film thickness of 20, 50, and 100 nm. The scattering profile of each sample was measured at the incident photon energy of 280 and 296 eV. As a result, it is suggested that the chemical-structure-size distribution in the resist thin films depends on the resist film thickness. It is confirmed that the GI-RSoXS method is very effective to evaluate the chemical-structure-size distribution of resist thin films.

Fine-tuning physical properties by structural modification is important for developing organic semiconducting materials. In this work, we designed and synthesized new electron-accepting compounds containing naphtho[1,2-c:7,8-c']bis([1,2,5]thiadiazole (vNTz) or naphtho[1,2-c:5,6-c']bis[1,2,5]thiadiazole (NTz) groups as electron-accepting units; these units are structural isomers. The vNTz-based compounds have an arch-shaped molecular backbone with C_2v symmetry, whereas the NTz-based compound forms an S-shaped molecular backbone with C_2h symmetry. Property measurements showed unique behavior originating from the vNTz core. An organic solar cell comprising the vNTz-based compound and poly(3-hexylthiopehene) showed a power conversion efficiency of 2.06%. This result demonstrates the potential of vNTz as an electron-accepting unit in organic semiconducting materials.

Photopolymer materials have been widely used in some advanced industries owing to their practicability, low-cost, and ecological advantage. One of the key components of these photopolymer materials is a molecule that releases acidic species upon a photon trigger (known as Photo-acid generators, PAGs). Recently, PAGs have attracted much attention with novel technologies such as near-infrared CTP imaging, 3D printing, and EUV lithography, and are required to have various functions and sophisticated features. This review article summarizes recent advances in the molecular design and function of PAGs, which are required to respond to the increasing applications of the photopolymer materials in advanced industries.