Wang Cheng, Chen Pin-Jie, Hsueh Chun-Hway
Department of Materials Science and Engineering, National Taiwan University, Taipei 10617, Taiwan.
ACS Omega. 2022 May 26;7(22):18780-18785. doi: 10.1021/acsomega.2c01565. eCollection 2022 Jun 7.
We deposited Au-Cu-Si, an Au-based thin-film metallic glass (TFMG) of ∼50 nm thickness, as the activation layer for propagating surface plasmon resonance (PSPR)-based sensors on a BK7 glass substrate to substitute the commonly used gold layer. The film composition was tuned to yield the maximum Au content (∼65 at %), while the structure remained amorphous. The results showed that the Au-based TFMG could support surface plasmon resonance and gave rise to the extinction in the angle-resolved reflection spectrum. Using deionized water and ethyl alcohol with the refractive index difference of ∼0.03 as the analytes, the angle shift given by Au-based TFMG was 4° compared to 5° given by the Au film. Hence, Au-based TFMG is feasible to be used as the activation layer in PSPR-based sensors. Compared to the Au film, Au-based TFMG has the advantages of being less expensive, lacking grain boundary scattering, better adhesion to the substrate, and higher resistance to scratch and corrosion because of its amorphous structure with excellent mechanical properties.
我们在BK7玻璃基板上沉积了厚度约为50 nm的Au-Cu-Si（一种基于金的薄膜金属玻璃（TFMG）），作为基于表面等离激元共振（PSPR）传感器的激活层，以替代常用的金层。调整薄膜成分以获得最大金含量（约65原子%），同时结构保持非晶态。结果表明，基于金的TFMG能够支持表面等离激元共振，并在角度分辨反射光谱中产生消光。使用折射率差约为0.03的去离子水和乙醇作为分析物，基于金的TFMG给出的角度偏移为4°，而金膜给出的角度偏移为5°。因此，基于金的TFMG可作为基于PSPR的传感器中的激活层。与金膜相比，基于金的TFMG具有成本更低、无晶界散射、与基板附着力更好以及由于其具有优异机械性能的非晶结构而具有更高的耐刮擦和耐腐蚀性等优点。
