UV-Activated Small Molecule Inhibitors for Patterned Area Selective Deposition

This award will aid in the innovation of chemical processes to expand manufacturing capabilities in next-generation semiconductor electronics. Frontier semiconductor device architectures require the ability to pattern materials in 3D nanoscale geometries, which is accomplished by patterning deposition layers on the surfaces of computer chips. To date, manufacturing processes have been established which employ molecules (chemicals) to block deposition on some material surfaces (e.g. material A), followed by a deposition process which forms material on other surfaces (e.g. on materials B and C). In this award, researchers at the University of Missouri aim to provide another level of control in these processes by identifying molecules which can be locally activated using patterned UV light to block deposition in selected areas. This will provide the ability to pattern deposition on different regions of one material (e.g. material A) or across varying materials (e.g. different regions of materials A, B, and C), which will simplify chemical processes in the manufacturing of semiconductor electronics while expanding capabilities. This effort will ensure leadership in technology development in this critical area. These research activities will be complemented with the development of hands-on interactive learning modules to make semiconductor manufacturing processes tangible and engaging for the general public including elementary school students. This project will combine machine-learning guided experimental exploration and computational mechanistic understanding to both discover and understand the mechanisms for small molecule inhibitors (SMIs) which are activated by UV light exposure. Researchers will steer the semi-autonomous experimental system using multi-objective Bayesian optimization and active learning to efficiently navigate chemical space and identify what molecular features drive varying surface interactions of small molecules with and without UV-irradiation. Density functional theory (DFT) modeling will aid in identifying what chemical features drive the desired reactivity behaviors to establish fundamental understanding of the specific mechanistic pathways leading to the target molecular properties. Champion molecule candidates will be studied using environmental scanning electron microscopy (eSEM) under different pressures, temperatures, and e-beam settings to quantify spatial resolution and selectivity of irradiation-induced inhibition, and understand the contributions of reaction kinetics, quenching, and side reactions in the performance of UV-activated SMIs. This work will help researchers understand the chemistry necessary to establish UV-activated SMIs and provide insights to guide further development of advanced semiconductor manufacturing processes. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.