磁控濺鍍成長摻雜型鋅鎵氧化物透明導電薄膜之光電特性研究

Electrical, optical and structured properties of gallium doping zinc oxide thin films prepared by r.f. magnetion sputtering

林詩萍(Shih-Pin Lin)

指導教授 ： 邱傳聖

元智大學/工程學院/機械工程學系/碩士(2006年)

https://doi.org/10.6838/YZU.2006.00083

摘要

本研究討論以氧化鎵與氧化鋅雙靶共濺鍍方式於玻璃基板成長鋅鎵氧化物 (gallium-doping zinc oxide, GZO)透明導電薄膜其光學、電性與顯微結構等特性。實驗結果顯示，室溫成長於玻璃基板的不同鎵含量成分組成GZO薄膜，皆呈現為六方纖維鋅結構且具有高(0002) C軸擇優取向。在SEM微觀分析中，可以發現隨著鎵成分含量提高，其GZO薄膜晶粒尺寸隨之增加。在光學性質量測部分，在GZO薄膜厚度為 200 nm時，在波長400 nm ~ 700 nm可見光範圍其平均光學穿透率約80%，能隙約為3.4 eV。霍爾效應量測結果顯示，GZO薄膜其鎵含量為5.0 wt.%時，具有最低電阻率2.96×10^-3 Ω-cm，其載子濃度為2×10^20 /cm^3，霍爾移動率為9.18 cm^2/V-s。為了提升GZO薄膜其光電特性，進一步以提高鍍膜溫度方式成長GZO薄膜，實驗結果顯示隨著增加GZO薄膜沉積溫度，其電阻率降低，而霍爾移動率與載子濃度各呈現增加的趨勢。實驗結果顯示，當基板溫度提升至500℃，其電阻率降低為3.33×10^-4 Ω-cm，其載子濃度為1.61×10^21 /cm^3，霍爾移動率為11.60 cm^2/V-s。

關鍵字

鋅鎵氧化物 ； 濺鍍 ； 透明導電薄膜 ； 室溫

並列摘要

Relationship among the optical, electrical properties and microstructures of transparent gallium-doping zinc oxide (GZO) films on glass substrate using a co-sputtering technique with varying sputtering power of Ga2O3 target as the Ga doping source was discussed. The experimental results showed the deposited GZO thin films at room temperature were polycrystalline with a hexagonal wurtzite structures and preferred orientation along (0002) plane. The SEM micrographs exhibited the grain size increases as function of the Ga content. The average optical transmittance of a 200 nm-thick film in the 400 ~ 700 nm visible region is about 80%. The optical band gap of GZO films was calculated to be about of 3.4 eV. GZO films with a 5 wt.% Ga content show lowest resistivity of 2.96×10^-3 Ω-cm, carrier concentration of 2×10^20 /cm^3 and Hall mobility of 9.18 cm^2/V-s, respectively. In order to improve the photoelectric property of GZO thin film, GZO films were prepared with a elevated substrate temperature. The lowest electrical resistivity of 3.33×10^-4 Ω-cm , high carrier concentration of 1.61×10^21 /cm^3 and Hall mobility of 11.60 cm^2/V-s, were obtained for the GZO thin films deposited with the substrate temperature of 500℃.

並列關鍵字

GZO ； sputtering ； TCO film ； room temperature

參考文獻

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