Abstract This research presents the study on the structural-phase states and magnetoresistive properties of thin nanogranular film alloys based on Cu and Co with a total concentration of Co in the range of 15 ≤ x ≤ 71 at%. The analyses for the unannealed and annealed thin films with a thickness d = 20 nm, have been performed. The films have been annealed in the temperature range from 300 to 800 K for 20 min. It found that the heat treatment within the range from 600 to 800 K led to an increase in the magnetoresistance and coercive force due to the growth of Co granules size under heat treatment and partial decomposition of the fcc-Cu(Co) solid solution. The highest magnitudes of the magnetoresistance were found in the as-deposited film alloys featured by the total concentration of Co x = 21 at%, which consist of Cu(Co) solid solution made of fcc-Cu and superparamagnetic Co granules (size L = 2 ÷ 5 nm). Interestingly, the thin film alloys with an increased concentration of Co x ≥ 50 at% exhibited anisotropic magnetoresistance.

中文翻译：

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Cu和Co共蒸镀薄膜合金的结构相态和磁阻性能

摘要 本研究对基于铜和钴的纳米颗粒薄膜合金的结构相态和磁阻性能进行了研究，其中 Co 的总浓度在 15 ≤ x ≤ 71 at% 的范围内。对厚度 d = 20 nm 的未退火和退火薄膜进行了分析。薄膜已在 300 至 800 K 的温度范围内退火 20 分钟。研究发现，由于热处理下 Co 颗粒尺寸的增长和 fcc-Cu(Co) 固溶体的部分分解，在 600 到 800 K 范围内的热处理导致磁阻和矫顽力增加。在沉积的薄膜合金中发现了最高量级的磁阻，其特征是 Co x 的总浓度 = 21 at%，由由 fcc-Cu 制成的 Cu(Co) 固溶体和超顺磁性 Co 颗粒（尺寸 L = 2 ÷ 5 nm）组成。有趣的是，Co x 浓度增加≥ 50 at% 的薄膜合金表现出各向异性磁阻。