An Jihwan, Usui Takane, Logar Manca, Park Joonsuk, Thian Dickson, Kim Sam, Kim Kihyun, Prinz Fritz B
Department of Mechanical Engineering, ‡Department of Materials Science and Engineering, and §Department of Applied Physics, Stanford University , Stanford, California 94305, United States.
ACS Appl Mater Interfaces. 2014 Jul 9;6(13):10656-60. doi: 10.1021/am502298z. Epub 2014 Jun 27.
High-k, low leakage thin films are crucial components for dynamic random access memory (DRAM) capacitors with high storage density and a long storage lifetime. In this work, we demonstrate a method to increase the dielectric constant and decrease the leakage current density of atomic layer deposited BaTiO3 thin films at low process temperature (250 °C) using postdeposition remote oxygen plasma treatment. The dielectric constant increased from 51 (as-deposited) to 122 (plasma-treated), and the leakage current density decreased by 1 order of magnitude. We ascribe such improvements to the crystallization and densification of the film induced by high-energy ion bombardments on the film surface during the plasma treatment. Plasma-induced crystallization presented in this work may have an immediate impact on fabricating and manufacturing DRAM capacitors due to its simplicity and compatibility with industrial standard thin film processes.
高介电常数、低漏电流薄膜是具有高存储密度和长存储寿命的动态随机存取存储器（DRAM）电容器的关键组件。在这项工作中，我们展示了一种方法，通过沉积后远程氧等离子体处理，在低工艺温度（250°C）下提高原子层沉积的BaTiO3薄膜的介电常数并降低其漏电流密度。介电常数从51（沉积态）增加到122（等离子体处理后），漏电流密度降低了一个数量级。我们将这种改善归因于等离子体处理期间高能离子对薄膜表面的轰击所引起的薄膜结晶和致密化。由于其简单性以及与工业标准薄膜工艺的兼容性，这项工作中呈现的等离子体诱导结晶可能会对DRAM电容器的制造产生直接影响。
