采用直流磁控溅射的方式,在浮法玻璃衬底上制备了氧化铟锡(ITO)薄膜。通过改变薄膜沉积时间,制备出不同厚度的ITO薄膜。随着膜厚由16 nm逐渐增大到271 nm,其结晶程度得到增强,对应的载流子浓度由4.79×10 ²⁰ cm ^-3增大到2.41×10 ²¹ cm ^-3,表面等离子体共振(SPR)波长由1802 nm逐渐蓝移到1204 nm,实现了近红外区域SPR波长较宽范围的可控调节。采用Drude自由电子气模型,对不同厚度ITO薄膜的SPR波长进行了理论计算,进一步证明了SPR波长的有效调节取决于膜厚对载流子浓度的影响作用。

The tin-doped indium oxide (ITO) thin films are fabricated on the float glass substrates by the direct current (DC) magnetron sputtering method. The ITO thin films with different thicknesses are fabricated by changing the deposition time. As the film thickness gradually increases from 16 nm to 271 nm, the crystallinity is enhanced and the corresponding carrier concentration is increased from 4.79×10 20 cm -3 to 2.41 ×10 21 cm -3. Thus the corresponding surface plasmon resonance (SPR) wavelength blueshifts from 1802 nm to 1204 nm. The controllable modulation of near infrared SPR wavelength within a relatively broad range is realized. The SPR wavelength of the ITO films with different film thicknesses are theoretically calculated by using the Drude free electron gas model, which further confirms that the effective modulation of SPR wavelength is determined by the influence of film thickness on carrier concentration.