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Indium oxide is currently in the spotlight of the micro-optoelectronics industry because of its high carrier concentration, electrical conductivity, and transmittance in the visible-light region. Among the methods of depositing indium oxide, atomic layer deposition (ALD) has the advantage of thickness control and conformality. In addition, it has high conformality, but a slow deposition rate. Therefore, plasma-enhanced ALD, which uses highly reactive radicals, is receiving attention. ALD is based on a self-limiting reaction. Therefore, the selection of the precursor is important because the ligand that reacts with the surface has a significant influence on the reaction. Herein, DIP-3 and DIP-4, amine/alkyl-based precursors, were developed based on previously used precursors. The growth characteristics of indium oxide deposited through the O2 plasma-enhanced ALD process using these two precursors differed depending on the precursor used. Alkyl-based DIP-4 resulted in a higher growth rate (∼1 Å per cycle) compared to that of amine-based DIP-3. The difference in the properties is related to the new ligands of the two precursors. DIP-4 was stably adsorbed on the surface with an energy reduction of 173 kJ mol−1, which is greater than that of DIP-3. Owing to its small size and added ligand, DIP-4 covered the substrate surface quickly and accelerated the film growth. The consumption of more hydroxyl groups can lead to the formation of more nuclei, and the coarsening of the crystals based on this phenomenon is associated with an increase in the growth per cycle (GPC). [ABSTRACT FROM AUTHOR]

The utilization of a zirconium oxide (ZrO2) thin film as the insulator in a metal–insulator–semiconductor (MIS) capacitor to enhance the characteristics of thin‐film transistors is investigated. Although the high crystallinity of ZrO2 is favorable to achieving higher capacitance density in metal–insulator–metal capacitors with ZrO2 thin films, it decreases the capacitance with increasing applied bias in Mo/ZrO2/InGaZnO (IGZO)‐structured MIS capacitors. Through comprehensive physical, chemical, and electrical characterizations, this study investigated the mechanism underlying the decreasing capacitance with increasing the applied bias in the accumulation state of the Mo/ZrO2/IGZO‐structured MIS capacitor depending on the crystallinity of ZrO2. Furthermore, the investigation identifies the optimal crystal structure of ZrO2 thin films for IGZO‐based MIS capacitors, highlighting the importance of forming meso‐crystalline structures in high dielectric constant (k) materials to enhance the k value and mitigating the decrease in capacitance caused by the accumulated carrier loss through grain boundaries of ZrO2. [ABSTRACT FROM AUTHOR]