Influence of Thickness on Surface Plasmon Resonance Wavelength of ITO Thin Film

• 1、State Key Laboratory of High Power Semiconductor Laser of Changchun University of Science
• 2、School of Materials Science and Engineering,Changchun University of Science and Technology
• 3、State Key Laboratory of Supramolecular Structure and Materials,Institute of Theoretical Chemistry,Changchun 130022

Abstract：Tin-doped indium oxide (ITO) thin films with cubic polycrystalline iron manganese structure were deposited on float glass substrates by the direct current (DC) magnetron sputtering. For controllable modulating the surface plasmon resonance (SPR) wavelength of ITO films, we have prepared ITO films with the different thicknesses by changing the deposition times. As the film thickness gradually increased from 16nm to 271nm, the crystallinities of ITO films are enhanced. And the carrier concentrations of ITO films are increased from 4.79*10^20cm^-3 to 2.41*10^21cm^-3, corresponding the SPR wavelengths show gradual blue shifts from 1802nm to 1204nm. The above results indicated that the controllable modulation of SPR wavelengths were realized in near infrared region by modulating carrier concentrations of the different film thicknesses. The dielectric cross-over wavelength constants of different film thickness of the ITO films were calculated using the Drude free electron gas model, further demonstrating that the SPR wavelengths are availably modulated by corresponding carrier concentrations of film thicknesses.

Keywords： surface plasmas ITO film film thickness carrier concentrations