Investigation of optic fiber sensor based on surface plasmon resonance for monitoring the concentration of plasma deposited hydrophilic functional groups on material surfaces

An optical fiber sensor based on the surface plasmon resonance (SPR) is proposed as a way to monitor the concentration of plasma deposited hydrophilic functional groups on material surfaces by the SPR dip shift in wavelength. The SPR optical fiber sensor was installed in the isopropanol (IPA) treatment system in order to measure the surface hydrophilicity of the deposited sample during IPA plasma treatment. The SPR dip shift in the spectrum was related to the water contact angle (WCA) for the same IPA plasma treatment conditions. Moreover, the compact size SPR fiber sensor was able to install in plasma treatment chamber and measure hydrophilicity in real time.