Ekgasit Sanong, Thammacharoen Chuchaat, Yu Fang, Knoll Wolfgang
Sensor Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
Appl Spectrosc. 2005 May;59(5):661-7. doi: 10.1366/0003702053945994.
The influence of the metal film thickness (i.e., the chromium adhesion promoting film and the gold film) on the sensitivity of surface plasmon resonance (SPR) signals (i.e., resonance angle shift and reflectance change) towards the thickness variation of the nonabsorbing dielectric film is investigated. The sensitivity of reflectance change decreases when a thick chromium film or a thin gold film is employed. Its linear range becomes narrower as the thickness of the metal films increases. The sensitivity and linear range of the resonance angle shift are not affected by the thickness variation of the metal films. The phenomena were theoretically explained based on the attenuated total reflection (ATR) generated evanescent field at the prism/metal interface and the SPR-generated evanescent field at the metal/dielectric interface.
研究了金属膜（即铬粘附促进膜和金膜）厚度对表面等离子体共振（SPR）信号（即共振角偏移和反射率变化）对非吸收性介电膜厚度变化的灵敏度的影响。当使用厚铬膜或薄金膜时，反射率变化的灵敏度降低。随着金属膜厚度的增加，其线性范围变窄。共振角偏移的灵敏度和线性范围不受金属膜厚度变化的影响。基于棱镜/金属界面处的衰减全反射（ATR）产生的倏逝场和金属/介电界面处的SPR产生的倏逝场，从理论上解释了这些现象。
