低溫燒結氧化鋅奈米薄膜之特性研究

A Characteristic Study of Low Temperature Sintered Zinc Oxide Nano Films

姚潔宜(Jay-Yi Yao)

指導教授 ： 林啟瑞 ； 蘇春熺

國立臺北科技大學/機電學院/製造科技研究所/碩士(2006年)

https://doi.org/10.6841/NTUT.2006.00103

摘要

本研究先以自行組裝之球磨機(Ball mill)將純氧化鋅(ZnO)粉末粒徑研磨至奈米尺寸，然後滴塗於n型矽晶圓與石英基材上，再置入傳統高溫爐內燒結為奈米厚度之薄膜。
由於粉末粒徑經細小化而大幅提升其比表面積，因此降低其燒結溫度。製得之ZnO薄膜經XPS(X-ray photoelectron spectroscopy)鑑定其Zn2P3/2鍵結能量為1022.1 eV且其O1s鍵結能量為532.5 eV；其可見光穿透率(Transmission)可達至91%；經紫外光激發ZnO薄膜內之電子，並配合30.0 V偏壓時可量測出最大電容值約為2.3 n F電流-電壓(I-V)量測結果顯示其阻抗值為344.8kΩ。
本研究亦利用射頻磁控濺鍍系統沉積ZnO，以便與燒結之ZnO薄膜進行比較。由X-ray檢測結果發現沉積所得之ZnO膜具有纖鋅礦的結構，屬於六方晶系，其垂直c 軸平面為最緊密堆積面，濺鍍後薄膜具有c 軸從優取向。而燒結之ZnO薄膜則以結晶面(103)最為顯著。
在介電特性上，實驗中另外探討以不同溫度燒結ZnO陶瓷電容其微結構對介電常數及介電損失之影響。結果發現結構緻密性愈佳，其介電常數值也隨之提升。

關鍵字

氧化鋅薄膜 ； 燒結 ； 球磨 ； C-V特性 ； I-V特性 ； 穿透率

並列摘要

This study utilized a self-assembled ball mill to mechanically grind pure zinc oxide (ZnO) powders into nanoscales. The ZnO nano-powders were then blended with alcohol and polyvinyl alcohol (PVA) and spread onto silicon wafer and quartz substrates through dip coating process, and were finally sintered at different temperature into ZnO nano-films using a programmable furnace. The sintering temperatures for these nano-films were relatively lowered due to the miniaturized powder size and the highly raised specific surface area (SSA).
The average size of ZnO powder was successfully reduced from original 1921 nm to 35 nm, and hence ZnO films can be formed at a sintering temperature of as low as 300 ℃. The surface microstructures of the as-prepared ZnO films were examined using field emission scanning electron microscope (FESEM) and atomic force microscope (AFM), and binding energies of Zn 2P3/2 and O 1s in such films were found to be 1022.1 eV and 532.5 eV, respectively, using x-ray photoelectron spectroscopy (XPS). A current of 14.27 mA under a maximum input voltage of 0.07 V can be found for the ZnO nano-films. An optical transmission of visible lights for sintered ZnO nano-films can be as high as 91%. The capacitance-voltage (C-V) curves were also measured for the obtained nano-films while exposed to ultraviolet lights. The measured capacitance was nearly 2.3 nF at a bias potential of 30 V, and the voltage-current (I-V) characteristic curve show that can be obtained under a maximum output current of 0.29 m A maximum input voltage of 0.1 V .The resistance is 344.8 kΩ).
On the other hand, this study used RF magnetron sputtering of ZnO film as a comparison. In the experiment, hexagonal wurtzite ZnO thin films are found to be deposited on Si (100) by RF-magnetron sputtering system. The close-packed c-axis plane in films perpendicular to the Si substrate is obtained. However, dielectric constants and dielectric losses of ZnO ceramic capacitors that fabricated at different sintering temperatures, were measured. It is observed that the dielectrivity of as-sintered capacityors increases with their compactness.

並列關鍵字

ZnO thin film ； Sintering ； Ball mill

參考文獻

3 Numerical Data and Functional Relationships in Science and Technology./V.22, Subvolume a. Intrinsic Properties of Group ⅣElements and Ⅲ–Ⅴ, Ⅱ–Ⅵ and Ⅰ–ⅦCompounds., Berlin:/Springer–Verlag,/ 1987

4 Y. Chen, D. M. Bagnall, H. Koh, K. Park, Z. Zhu, T. Yao, “Plasma assisted molecular beam epitaxy of ZnO on c -plane sapphire: Growth and characterization,” J. Appl. Phys., 84, 3912, 1998

5 W.H. Hirschwald et al.: “Zinc Oxide,” Current Topics in Materials Science; Vol. 7; Chapter 3; pp. 143-482; 1981

6 T.K. GUPTA: “Application of Zinc Oxide Varistors,” J. Am.Ceram.Soc.; Vol. 73,Vol. 7, pp. 1817-1840, 1990

9 R. W. Anthony, “Basic Solid State Chemistry,” pp.37, 1988