Chung, Hong Keun Jeon, Jihoon Kim, Han Jang, Myoungsu Kim, Sung-Chul Won, Sung Ok Baek, In-Hwan Chung, Yoon Jang Han, Jeong Hwan Cho, Sung Haeng Park, Tae Joo Kim, Seong Keun 2024-07-18T02:30:11Z 2024-07-18T02:30:11Z 2024-07-18 2024-08 0169-4332 https://pubs.kist.re.kr/handle/201004/150239 Despite SrTiO 3 (STO) possessing a high dielectric constant, its application as a capacitor dielectric in dynamic random-access memory(DRAM) capacitors faces challenges due to the high-temperature annealing for crystallization, its compositional inhomogeneity, and the high leakage currents of STO films. To address these issues, we employ atomic layer deposition(ALD) of STO films onto Pt substrates at elevated temperatures(340 -380 degrees C). The use of low-reactivity Pt electrodes effectively mitigates the initial growth of excess Sr, ensuring enhanced compositional uniformity along the film growth direction. Coupled with ALD at high temperatures, this approach facilitates the crystallization of STO films in the as-grown state, further enhancing the crystallinity with increasing film thickness. Subsequent low-temperature post-deposition annealing (PDA) at 400 and 500 degrees C achieves full crystallization. This process results in a remarkable increase in the dielectric constant, reaching approximately 150. Furthermore, the absence of microcracks after PDA, attributed to the formation of adequately dense films, contributes to substantially improved dielectric properties. Consequently, these STO films exhibit an exceptionally low equivalent oxide thickness of 0.34 nm coupled with an ultralow leakage current of 3.7 x 10-8 A/cm 2 at an operation voltage of 0.8 V, promising for advancing DRAM capacitors. This study presents a pathway for the sustainable scaling of DRAMs, addressing challenges in ALD-grown STO films. English Elsevier BV Low temperature crystallization of atomic-layer-deposited SrTiO3 films with an extremely low equivalent oxide thickness of sub-0.4 nm Article 10.1016/j.apsusc.2024.160243 1 Applied Surface Science, v.664 Applied Surface Science 664 Y scie scopus 001265951500001 2-s2.0-85192672816 Chemistry, Physical Materials Science, Coatings & Films Physics, Applied Physics, Condensed Matter Chemistry Materials Science Physics Article THIN-FILMS STRONTIUM COMPLEXES SEED LAYER ALD CAPACITORS PLASMA GROWTH PRECURSORS SR SrTiO3 DRAM capacitor Atomic layer deposition Equivalent oxide thickness