Title: Thermal Atomic Layer Deposition of Transition Metal Phosphide Thin Films

Program: Materials Science and Engineering PhD

Committee Chair: Elton Graugnard

Committee: Elton Graugnard, David Estrada, Paul Davis, Kent Zhuang

Abstract: The continued dimensional scaling of features within semiconductor devices has placed immense pressure on the materials that are traditionally used to fabricate devices. Interconnects, which are the conductors that connect individual microelectronic device components together to enable signal transmission and power distribution throughout the device, are beginning to suffer decreases in performance metrics due to increased resistivity as a result of dimensional scaling. In order to enable the continued trend of dimensional scaling to satisfy the ever-increasing technological demands, new materials that can continue to provide sufficient performance at the size scales required for next generation technologies are required. Topological semimetals is one class of materials that have been proposed as an alternative interconnect material due to the favorable resistivity scaling that these materials are predicted to exhibit.
In order for these materials to be candidates for integration into next generation device architectures, scalable synthesis methods, such as atomic layer deposition (ALD) are required. ALD is a vapor phase deposition technique for synthesizing films with angstrom level control, which makes it uniquely suited to depositing films at the size scales required for next generation technology nodes. In addition, insights into how the processing conditions impact the performance of the deposited films is also of importance. In this work, I report on two new binary ALD chemistries for the deposition of new potential interconnect materials which have been predicted to exhibit favorable resistivity scaling trends that differ from currently used metal conductors. Methods for improving the quality of deposited films are also discussed. Additionally, the challenges and opportunities that were observed in this foundational work are presented to provide a foundation for future studies that build upon this work and advance these materials closer to potential integration into production devices.