The potential implementation of extreme ultraviolet (EUV) lithography into next generation device processing is bringing urgency to identify resist materials that optimize EUV lithographic performance. Inorganic/organic hybrid nanoparticles or clusters constitute a promising new class of materials, with high EUV sensitivity from the core and tunable chemistry through the coordinating ligands. Development of a thorough mechanistic understanding of the solubility switching reactions in these materials is an essential first step toward their implementation in patterning applications but remains challenging due to the complexity of their structures, limitations in EUV sources, and lack of rigorous in situ characterization. Here we report a mechanistic investigation of the solubility switching reactions in hybrid clusters comprised of a small HfOx core capped with a methacrylic acid ligand shell (HfMAA). We show that EUV-induced reactions can be studied by performing in situ IR spectroscopy of electronirradiated films using a variable energy electron gun. Combining additional ex situ metrology, we track the chemical evolution of the material at each stage of a typical resist processing sequence. For instance, we find that a crosslinking reaction initiated by decarboxylation of the methacrylate ligands under electron irradiation constitutes the main solubility switching mechanism, although there are also chemical changes imparted by a typical the post application bake (PAB) step alone. Lastly, synchrotronbased IR microspectroscopy measurements of EUV-irradiated HfMAA films enable a comparison of reactions induced by EUV vs electron beam irradiation of the same resist material, yielding important insight into the use of electron beam irradiation as an experimental model for EUV exposure.

Materials exhibiting higher mobilities than conventional organic semiconducting materials such as fullerenes and fused thiophenes are in high demand for applications in printed electronics. To discover new molecules in the heteroacene family that might show improved charge mobility, a massive theoretical screen of hole conducting properties of molecules was performed by using a cloud-computing environment. Over 7 000 000 structures of fused furans, thiophenes and selenophenes were generated and 250 000 structures were randomly selected to perform density functional theory (DFT) calculations of hole reorganization energies. The lowest hole reorganization energy calculated was 0.0548 eV for a fused thioacene having 8 aromatics rings. Hole mobilities of compounds with the lowest 130 reorganization energy were further processed by applying combined DFT and molecular dynamics (MD) methods. The highest mobility calculated was 1.02 and 9.65 cm2/(V s) based on percolation and disorder theory, respectively, for compounds containing selenium atoms with 8 aromatic rings. These values are about 20 times higher than those for dinaphthothienothiophene (DNTT).

Quantum chemical calculations are necessary to develop advanced emitter materials showing thermally-activated delayed fluorescence (TADF) for organic light-emitting diodes (OLEDs). However, calculation costs become problematic when more accurate functionals were used, therefore it is judicious to use a multimethod approach for efficiency. Here we employed combinatorial chemistry in silico to develop the deep blue TADF materials with a new concept of homo-junction design. The homo-junction materials containing TADF candidates designed by calculation were synthesized and analyzed. We found that these materials showed the emission from charge transfer (CT) state, and the clear delayed emission was provided in solid state. Because the homo-junction TADF materials showed three exponential decayed emission in solid state, we employed novel four-state kinetic analysis.

Completely linear: a general and practical palladium-catalyzed linear-selective Negishi coupling of 3,3-disubstituted allylzinc reagents with aryl, heteroaryl and vinyl electrophiles at ambient temperature is described. This method provides an effective means to access a wide range of prenylated arenes or skipped dienes in a completely linear-selective fashion, as demonstrated by a concise synthesis of the anti-HIV natural product siamenol. Finally, DFT calculations shed light on the origin of the excellent regioselectivity observed with the current catalyst system.

The characterization of water-based corrosion, geochemical, environmental and catalytic processes rely on the accurate depiction of stable phases in a water environment. The process is aided by Pourbaix diagrams, which map the equilibrium solid and solution phases under varying conditions of pH and electrochemical potential. Recently, metastable or possibly stable nanometric aqueous clusters have been proposed as intermediate species in non-classical nucleation processes. Herein, we describe a Group Additivity approach to obtain Pourbaix diagrams with full consideration of multimeric cluster speciation from computations. Comparisons with existing titration results from experiments yield excellent agreement. Applying this Group Additivity-Pourbaix approach to Group 13 elements, we arrive at a quantitative evaluation of cluster stability, as a function of pH and concentration, and present compelling support for not only metastable but also thermodynamically stable multimeric clusters in aqueous solutions.