Gu Ke, Guan Yicheng, Hazra Binoy Krishna, Deniz Hakan, Migliorini Andrea, Zhang Wenjie, Parkin Stuart S P
Max Planck Institute of Microstructure Physics, Halle, Germany.
Nat Nanotechnol. 2022 Oct;17(10):1065-1071. doi: 10.1038/s41565-022-01213-1. Epub 2022 Sep 22.
The fabrication of three-dimensional nanostructures is key to the development of next-generation nanoelectronic devices with a low device footprint. Magnetic racetrack memory encodes data in a series of magnetic domain walls that are moved by current pulses along magnetic nanowires. To date, most studies have focused on two-dimensional racetracks. Here we introduce a lift-off and transfer method to fabricate three-dimensional racetracks from freestanding magnetic heterostructures grown on a water-soluble sacrificial release layer. First, we create two-dimensional racetracks from freestanding films transferred onto sapphire substrates and show that they have nearly identical characteristics compared with the films before transfer. Second, we design three-dimensional racetracks by covering protrusions patterned on a sapphire wafer with freestanding magnetic heterostructures. We demonstrate current-induced domain-wall motion for synthetic antiferromagnetic three-dimensional racetracks with protrusions of up to 900 nm in height. Freestanding magnetic layers, as demonstrated here, may enable future spintronic devices with high packing density and low energy consumption.
三维纳米结构的制造是开发具有小器件占位面积的下一代纳米电子器件的关键。磁记录赛道存储器将数据编码在一系列磁畴壁中，这些磁畴壁由电流脉冲沿着磁性纳米线移动。迄今为止，大多数研究都集中在二维赛道上。在此，我们介绍一种剥离和转移方法，用于从生长在水溶性牺牲释放层上的独立磁性异质结构制造三维赛道。首先，我们从转移到蓝宝石衬底上的独立薄膜创建二维赛道，并表明它们与转移前的薄膜具有几乎相同的特性。其次，我们通过用独立磁性异质结构覆盖蓝宝石晶片上图案化的凸起设计三维赛道。我们展示了对于高度高达900nm的凸起的合成反铁磁三维赛道的电流诱导畴壁运动。如本文所示，独立磁性层可能使未来的自旋电子器件具有高封装密度和低能耗。
