氧化銦錫薄膜與奈米結構兆赫頻段光學特性之研究

Abstract

我們使用富立業遠紅外光光譜以及兆赫波時域光譜的光學量測方法去探討氧化銦錫薄膜及氧化銦錫奈米柱的光學特性和電性。且對於不同厚度的薄膜(189nm ~ 961nm)，我們得到以下的特性： 樣品之電漿頻率隨著厚度變厚而變大，其值1600(rad.THz)到 1950 (rad.THz)。以Drude的自由載子模型的知載子散射時間為6∼7(fs)。且我們也同樣得到對應的載子漂流率跟載子濃度，分別為32∼34(cm2/Vs)和(2.8∼4.2)×1020。我們得到的這些電性結果可以跟霍爾量測到的結果做相對應的比較，且得到相近的數值。 同樣的，我們可以將這光學量測技術使用於奈米結構樣品的探討。在本論文裡面，我們將研究氧化銦錫的奈米柱結構，並引進Drude-Smith模型及等校介值理論來輔助分析。

We investigate the optical and electrical properties of Indium Tin Oxide (ITO) thin film and Indium Tin Oxide (ITO) nanocolumns with the optical characterization methods including Fourier Transform Infrared Spectroscopy (FTIR) and Terahertz Time Domain Spectroscopy (THz-TDS). For different thicknesses of the Indium Tin Oxide (ITO) thin films (189nm~961nm), the plasma frequencies are determined to be from 1600 (rad.THz) to 1950 (rad.THz), and scattering times are in the range of 6~7 fs based on the free electron Drude model. The mobilities of the above Indium Tin Oxide (ITO) thin films are determined to be 32~34cm2/Vs. The carrier concentration is verified to be in the range of (2.8~4.2)×1020. The electrical properties of the thin films derived from non-contact optical techniques agree well with those determined by the conventional Hall measurement. Similarly, the techniques are also introduced to the nanostructure materials, Indium Tin Oxide (ITO) nanocolumn. We study the optical and electrical properties of the sample with the Drude-Smith model and the effective medium approximation (EMA) which are demonstrated in the thesis.