Surface and Interface Investigation of Novel Materials for Future Applications in Logic and Memory Devices

Layered Transition Metal Dichalcogenides (TMDs) and Ferroelectric Hf0.5Zr0.5O2 (HZO) are the novel material systems investigated in this work for future applications in logic and memory technologies. Semiconductor TMDs exhibited promising electrical properties for device applications beyond silicon-based electronics. For the implementation of semiconductor TMDs into nano-electronic devices, challenges like a viable doping approach and a high-quality semiconductor-dielectric interface need to be addressed. This work provides surface engineering techniques to overcome the doping and dielectric deposition challenges for WSe2 and ReS2. Insitu XPS, AFM, and Raman are among the characterization techniques employed in this work to provide a thorough surface and interface analysis of WSe2 and ReS2. HZO thin films are considered potential materials for future ferroelectric memory devices because of being highly scalable and compatible with CMOS technology. Integration of ferroelectric HZO thin films into the commercial ferroelectric random-access memory (Fe-RAM) and ferroelectric field-effect transistor (Fe-FET) still needs considerable improvement. Therefore, the fundamental study of the evolution of the HZO interfaces remains to be systematically characterized. In this work, the HZO deposition process on metal and semiconductor is therefore investigated in detail by interrupting the ALD growth cycle and in-situ surface characterization using monochromatic XPS.