SBIR PHASE I: Self-Patterning Process for Conductive Oxide Contacts for Ferroelectric Thin Film Memory Devices

小行星9561650 该小型企业创新研究（SBIR）第一阶段项目将开发一种用于沉积和图案化RuO 2触点的新工艺，用于铁电薄膜电容器存储器件，如非易失性存储器（NVRAM）和超高密度动态随机存取存储器（DRAM）。 RuO 2已被证明与铁电膜如PZT（PbZr 1-xTixO 3）形成良好的接触;与具有金属接触如Pt的PZT器件相比，这导致显著更低的疲劳、更好的I-V特性和改善的时间依赖击穿特性。 然而，缺乏一个方便的处理技术，阻碍了在实际设备中的RuO 2接触的实施。 新工艺包括两个关键创新：首先，RuO 2薄膜将通过旋涂工艺沉积为金属有机前驱体，并在烧制前通过湿化学方法进行图案化。 这将实现比等离子体蚀刻更简单、损伤更小且更便宜的工艺，等离子体蚀刻是目前用于图案化RuO 2的唯一方法。 第二，金属有机前体将具有可光化学交联的有机基团。 该工艺将允许导电氧化物接触的光刻图案化，而不需要使用单独的抗蚀剂，因此节省了工艺步骤。 第一阶段将开发可溶性前体RuO 2具有有机取代基能够紫外线交联，存款这些材料在衬底上的旋涂工艺，演示光刻图案，并评估烧制RuO 2接触的质量。 这一发展将使先进的铁电薄膜器件的实际制造具有上级性能相比，目前的国家的最先进的。 所提出的技术的商业应用包括用于智能卡和寻呼机的非易失性存储器，以及用于计算机应用的千兆位级DRAM。

9561650 Rice This Small Business Innovation Research (SBIR) Phase I project will develop a new process for depositing and patterning RuO2 contacts for use in ferroelectric thin film capacitor memory devices such as non-volatile memories (NVRAMs) and ultra-high density dynamic random access memories (DRAMs). RuO2 has been shown to form a good contact with ferroelectric films such as PZT (PbZr1-xTixO3); this leads to substantially lower fatigue, better I-V characteristics, and improved time-dependent breakdown properties compared to PZT devices having metal contacts such as Pt. However, the lack of a convenient processing technology has impeded the implementation of RuO2 contacts in practical devices. The new process incorporates two key innovations: first, the RuO2 films will be deposited as metallorganic precursors by a spin-on process, and patterned by wet chemical methods before firing. This will enable a simpler, less damaging, and less expensive process than plasma etching, which is the only current method in use for patterning RuO2. Second, the metallorganic precursor will possess organic groups which are photochemical crosslinkable. The process will allow photolithographic patterning of the conductive oxide contact without requiring the use of a separate resist, thus saving process steps. Phase I will develop soluble precursors to RuO2 having organic substituents capable of UV crosslinking, deposit these materials on substrates by a spin-on process, demonstrate photolithographic patterning, and assess the quality of fired RuO2 contacts. This development will enable the practical fabrication of advanced ferroelectric thin film devices with superior performance compared to the current state-of-the-art. Commercial applications of the proposed technology include non-volatile memories for smart cards and pagers, and gigabit-scale DRAMs for computer applications.