The optical and electrical properties of Zinc Oxide films on the N/P silicon substrates 徐養鐘、范榮權
E-mail: 324891@mail.dyu.edu.tw
ABSTRACT
In this work, we investigated the ZnO thin film on the N/P type silicon substrates by the RF magnetron sputtering method. We study the opotical and electrical properties by IV-curve, photoconductivity and persistent photoconductivity. The thermal-emission is very important when metal connects to the semiconduct or in the experimental of N / P type silicon. The characteristic of non-ohmic contact is formed because of the carrier can not pass through the barrier. The energy barrier can be obtained by the Schottky effect model. Investigating the oxygen defect of ZnO thin film, we can use the optical absorption edge and energy gap by the photoconductivity and the persistent photoconductivity measurement. The persistent photoconductivity effect fitting curves corresponded to the stretch exponential effect [I(t)=Io(t)exp(-t/τ)β] indicates that defect exist in the energy gap with the 30.5meV from the conduction band.
Keywords : ZnO、thin film、Schottky、defect
Table of Contents
封面內頁 簽名頁 中文摘要 iii 英文摘要 iv 誌謝 v 目錄 vi 圖目錄 viii 表目錄 x 第一章 緒論 1 1.1 氧化鋅薄膜的發展 1 1.2 研究 動機 2 1.3 論文架構 2 第二章 基本原理 3 2.1氧化鋅薄膜概述 3 2.2 價帶與導帶 5 2.3 X光繞射分析儀 6 2.4金屬與半導體接面 傳輸機制 8 2.4.1熱游子放射 8 2.4.2熱游子場放射 10 2.4.3場放射 11 2.5光電導原理 12 2.6持續性光電導 18 2.6.1巨觀位障變 化模型 18 2.6.2巨大晶格鬆弛模型 19 2.6.3位能無序分佈模型 20 第三章 實驗方法與步驟 21 3.1 研究架構流程 21 3.2基座清 洗 22 3.3沉積ZnO薄膜 22 3.4氧化鋅薄膜鍍製 23 3.5 X-Ray繞射分析 23 3.6半導體特性(I-V curve)曲線量測 24 3.7光電導光譜 量測 25 3.8持續性光電導量測 27 第四章 結果與討論 28 4.1結晶結構 28 4.2半導體特性曲線 29 4.3光電導實驗分析 33 4.4持 續性光電導分析 37 第五章 結論 43 參考文獻 44
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