The 15th Global Conference on Materials Science and Engineering (CMSE 2026)

Abstract: With advanced research for dielectrics including capacitors in DRAMs, decoupling filters in microcircuits and insulating gates in transistors, a lot of demand for the new challenging of high-k materials in semiconductor industries has been emerged. This study explores and addresses the experimental approach for composite materials with one of the major concerns of high capacitance, and low leakage, as well as ease of integration technology. The characteristics of Al₂O₃ supported HfO₂ (AHO) thin films for a series of different Hf ratios with Al₂O₃ dielectrics by atomic layer deposition demonstrated as a candidate material. A composite AHO films with the homogeneous compositions of Al and Hf atoms into the Al-Hf-O mixed oxide system could stabilize the polycrystalline structure with increasing of dielectric constant (k) and decreasing of leakage current density, as well as a higher breakdown voltage than HfO₂ film on its own.

In this report, 70 nm thick AHO thin films with different composition of Al and Hf contents were prepared by atomic layer deposition technique on titanium nitride (TiN) and silicon dioxide (SiO₂) coated Si substrates. Photolithography and metal lift-off technique were used for the device fabrication of the metal-insulator-metal (MIM) capacitor structures. AHO films on TiN/SiO₂/Si were measured by semiconductor analyser and source/measure system with probe station in the voltage range from -5 to 5 V with a frequency range from 10 kHz to 1 MHz were used to conduct capacitance-voltage (C-V) measurements with low/medium frequency range and current-voltage (I-V) measurements. It was found that Au/AHO/ TiN/SiO₂/Si MIM capacitors demonstrate a capacitance density of 1.5 - 4.5 fF/μm² at 10 kHz, a loss tangent of 0.02 - 0.04 at 10 kHz, dielectric constant of 11.7 - 35.5 depending on the composition and a low leakage current of 1.7×10^-9 A/cm² at 0.5 MV/cm at room temperature. The acquired experimental results could show the possibility of compositional alloy thin films that could potentially replace or open new market for high-k challenges in semiconductor technology.

Keywords: Thin film, atomic layer deposition, high-k composites, laminated dielectrics.

Reference:
[1] Payne A. et al. Appl. Phys. Lett., 117(22), 221104 (2020)
[2] Wang Y. et al., Adv. in Mat. Phys. and Chem., 11, 7-19 (2021)

Biography: Dr. Jangyong Kim is currently working for Xi'an Jiaotong-Liverpool University (XJTLU) as an Associate Professor. He received Ph.D. degree in Solid State Electronics from the Department of Microelectronics and Applied Physics at Royal Institute of Technology (KTH) in Sweden (2007). He did postdoctoral research works in the Department of Micro- and Nanotechnology at the Technical University of Denmark (DTU) for MEMS (2008-2009), the Department of Applied Physics at Aalto University for multiferroic materials (2010-2012), and the Condensed Matter Physics Group at the University of Leeds for superconducting spintronics (2012-2015). He was working as a senior researcher in the Center for Biomolecular Nanotechnologies at Italian Institute of Technology (IIT) for transparent electronics (2015-2019), the Institute for Integrated Micro and Nano Systems at the University of Edinburgh for memristors. (2022-2024), and as a research professor in the school of Information Science and Technology at ShanghaiTech University (2019-2022). He presided over and participated in a number of national and international scientific research projects, and published more than 30 articles in internationally refereed journals and presented to international conferences and seminars.

His research interest is in the development of advanced functional thin films of materials with broad range of applications with interdisciplinary field which includes ceramic synthesis, thin film growth technology, lithographic processing solutions with micro- and nanofabrication (MEMS/NEMS), nano-scale engineering, bioelectronics, sensors, RF & microwaves, nanoelectronics, memory technologies, metamaterials, ferroelectric/dielectrics, semiconductors, superconductors, spintronics, and applying fundamental knowledge from nanoscience in scientific instrumentation, in-line material characterization and modifications. He is currently working on developing a MEMS based sensing devices with nano-fabrication and characterization of advanced functional electronic materials.