SBIR Phase I: An Enhanced Epitaxial Crystal Growth Method To Fabricate MTJ Having Ultra-Low Magnetic Damping

这个小型企业创新研究(SBIR)第一阶段项目将开发具有超小阻尼常数的磁性隧道结(MTJ)薄膜，用于低功率、高性能的自旋转移扭矩(STT)MRAM应用。本项目将利用增强型外延晶体生长方法制备具有新颖结构的MTJ磁记录层，以促进高质量磁性材料的晶体生长，减少缺陷和杂质，形成低磁阻的记录层薄膜。降低磁阻尼常数是降低STT-MRAM临界写入电流和写入功率而不折衷写入功率和热可靠性，提高STT-MRAM产品容限和成品率的最直接、最有效的方法。这种创新的MTJ制作方法不仅将产生超低损耗的恒磁记录层，而且比用于磁传感器的传统MTJ器件提供更好的噪声性能。此外，还将开发一个存储块来启动商业化努力。该项目更广泛的影响/商业潜力在于它能够制造具有低功耗和优异热可靠性的高性能STT-MRAM，以及具有更高信噪比的高质量基于MTJ的传感器。它的主要特点是在MTJ器件中提供了高质量的磁性薄膜，具有超低阻尼和低噪声。这种能力可能会在不同的学科产生广泛的影响，包括材料科学、自旋转移扭矩(STT)MRAM制造、先进的敏感磁传感器和生物传感器。由于STT-MRAM具有超高速、低功耗、非易失性、长寿命和良好的数据保存性等综合优异性能，STT-MRAM将作为一种颠覆性存储技术，使下一代高能效计算应用和移动设备成为可能。例如，它可以将处理器功耗降低90%，并为超高速计算机提供全新的集成内存解决方案。这种创新的MTJ制备方法将成为一种广泛使用的方法，以制备缺陷和杂质更少的磁性薄膜，从而为未来的纳米自旋电子器件提供超低的磁阻尼值。此外，它还将有助于更好地理解磁性薄膜中的磁阻尼现象。

This Small Business Innovation Research (SBIR) Phase I project will develop magnetic tunneling junction (MTJ) films having ultra-small damping constant for low-power, high performance spin transfer torque (STT) MRAM application. This program will take advantage of an enhanced epitaxial crystal growth method to fabricate MTJ magnetic recording layer with a novel structure to promote a high quality magnetic material crystalline growth with reduced defects and impurities to form low magnetic damping recording layer thin films. The magnetic damping constant reduction is the most direct and effective approach to decrease the critical write current and write power in STT-MRAM without any trade-off between the write power and thermal reliability, and to increase margin and yield of STT-MRAM product. This innovative MTJ fabrication method will not only create ultra-low damping constant magnetic recording layer but also provides better noise performance than traditional MTJ devices as used in magnetic sensor. Additionally, a memory block will also be developed to initiate commercialization efforts.The broader impact/commercial potential of this project is in its ability to make high performance STT-MRAM with low power and excellent thermal reliability and high quality MTJ-based sensor with improved signal-to-noise ratio. Its main attribute is that it offers high quality magnetic thin films with ultra-low damping and low noise in MTJ devices. This capability could have a broad impact in various disciplines, including material science, spin-transfer torque (STT) MRAM manufacturing, advanced sensitive magnetic sensor and biosensor. Due to its overall excellent performance, including ultra-high speed, low power, non-volatile, long life and good data retention, STT-MRAM will enable next generation power-efficient computing applications and mobile devices as a disruptive memory technology. For example, it can reduce processor power consumption by 90% and provide a brand-new integrated memory solution for ultra-fast computers. This innovative MTJ fabrication approach will become a widely useful method to make magnetic thin films with less defects and impurities and accordingly have ultra-low magnetic damping for future nano-spintronics devices. Furthermore, it will lead a better understanding of magnetic damping phenomena physics in magnetic thin films.