High Sensitive Sensors Utilizing Surface Plasmon Transmission Light in Organic Thin Films on Metal Grating

摘要

The surface plasmon resonance (SPR) spectroscopy is quite useful for evaluation of organic thin films and applications to high-performance organic sensors. Prism coupling is usually adopted to produce evanescent waves for the induction of SPR. However, the prism sometimes prevents miniaturization of the sensor and the measurement system tends to be complicated. Grating coupling is also used in the SPR method. Grating coupling enables the development of a small sensor and a simple measurement system, while commercially available optical discs can be used for substrates. Furthermore, the grating coupling method allows us to conduct measurements of transmission SPR (T-SPR). Peaks induced by SPR can be observed in the transmitted light spectra, and the intensity and peak wavelength are used for the SPR measurement. In this paper, high sensitive sensor utilizing the T-SPR method are demonstrated and the detection of ammonia gas was carried out under various humidity utilizing the T-SPR sensor.