Based on Atomic Layer Deposition Using a Single Mixed Precursor

- Published as an Inside Front Cover in the internationally renowned journal Journal of Materials Chemistry C

 (From left) Sang-Jun Park, MS-PhD integrated program; Se-Ryong Park, MS-PhD integrated program; Professor Tae-Jun Ha

Professor Tae-Jun Ha's research team (Department of Electronic Materials Engineering) successfully optimized the atomic layer deposition (ALD) process for fabricating indium-gallium-zinc oxide (IGZO) thin films using a liquid-delivery system with a single mixed precursor. They used this process to implement thin-film transistors and inverters with high mobility and voltage gain. This research, titled 'High-quality indium-gallium-zinc oxide films synthesized by atomic layer deposition using a single cocktail precursor based on a liquid-delivery system and their application in transistors and inverters,' was published in the Journal of Materials Chemistry C (IF: 6.4, JIF ranking: 80.3%), an internationally renowned journal in the field of applied physics by the Royal Society of Chemistry, and was selected for the Inside Front Cover.

 (Reference: https://doi.org/10.1039/D4TC01843E)

Atomic layer deposition (ALD) technology has recently gained significant attention for the high-quality deposition of IGZO thin films, which are widely used as oxide semiconductors in the channel layer of oxide thin-film transistors. However, for atomic layer deposition of four-component materials like conventional IGZO, each metal precursor must be deposited separately, making the process complex, deposition speed slow, and precise thickness control difficult. To address this issue, Professor Tae-Jun Ha's research team (Department of Electronic Materials Engineering), in collaboration with Samsung Display's Process Development Research Team, successfully achieved the first atomic layer deposition of IGZO thin films using a single mixed precursor based on a liquid-delivery system. The synthesized IGZO thin film exhibited high quality, including low surface roughness and a high metal-oxygen bonding ratio, and was used to implement oxide thin-film transistors and inverters based on the optimized process technology. ^The fabricated thin-film transⁱstor, based on the high-quality IGZO thin film, exhibited a high mobility of ov^er 20 cm² V？¹ s？¹ at an operating voltage of 5 V. Due to the low oxygen vacancy defects, it also maintained stable operating characteristics under bias stress for 20,000 seconds. Additionally, by applying the IGZO thin-film transistor, the team successfully implemented an NMOS inverter with a voltage gain of 31.48 and a noise margin of 0.2 V.

Meanwhile, this research was the result of a collaborative effort between the Process Development Research Team at Samsung Display, a client company, and the Interactive Display Research Center, led by Professor Tae-Jun Ha as the director, under the Kwangwoon University Innovation Future Challenge Project. The project was supported by the Carbon Neutral Industrial Core Technology Development Project, supervised by the Ministry of Trade, Industry, and Energy, and the New Product Development Program under Purchase Conditions, supervised by the Ministry of SMEs and Startups. Sang-Jun Park, the first author and an MS-PhD integrated program student, has been conducting research on next-generation semiconductor materials and electronic application devices since 2023, supported by the Research Scholarship for Doctoral Students from the Next-Generation Science and Technology Scholars Program. After obtaining his PhD from the university this August, he is set to join the IT Development Team of the Small and Medium Display Division at Samsung Display.

 Atomic layer deposition of IGZO thin films using a liquid-delivery system with a single mixed precursor, and performance analysis of thin-film transistors and inverters based on it

Cover paper published in Journal of Materials Chemistry C