简单轴和逆转过程在有图案的MRAM阵列中的分布
William Frost1, Robert Carpenter2, Sebastien Couet2
1School of Physics, Engineering and Technology, University of York, Heslington, YO10 5DD, UK. william.frost@york.ac.uk.
Scientific reports
|November 22, 2023
概括
较小的MRAM细胞由于不均而表现出更广泛的交换场分布. 较大的细胞显示较窄的分布,较薄的薄膜显示更均的轻轴方向,这对设备性能至关重要.
科学领域:
- 这就是Spintronics.
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
背景情况:
- 了解磁随机存储器 (MRAM) 细胞中的易轴分布对于设备切换和特征至关重要.
- 斯通纳-沃尔法特模型为分析磁性行为提供了基础.
研究的目的:
- 研究细胞大小和自由层厚度对MRAM阵列中切换场分布的影响.
- 为了比较不同尺寸的MRAM柱中的磁反转机制.
主要方法:
- 测量强制性作为应用场角的函数在20nm和60nm名义细胞大小的MRAM阵列中.
- 应用Stoner-Wohlfarth近似来确定简单轴方向的标准偏差.
- 分析自由层反转的激活体积.
主要成果:
- 更小的直径 (20纳米) 的MRAM细胞显示了更广泛的交换场分布 ([公式:参见文本]) 主要由支柱均性和边缘效应.
- 更大的直径 (60纳米) 的MRAM细胞表现出更窄的分布 ([公式:见文本]),随着自由层厚度的增加而扩大.
- 较大的柱子中较薄的自由层导致更均的轻轴方向.
- 激活体积分析表明,较小的支柱可以连贯逆转,而较大的支柱可以不连贯逆转.
结论:
- 支柱统一性和蚀刻过程显著影响交换场分布,特别是在较小的MRAM单元中.
- 将设备缩放到更小的尺寸需要改进制造控制以保持统一的磁性.
- 逆转机制从连贯转变为不连贯,随着柱子大小的增加.
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