本實驗藉由磁控濺鍍法沉積氧化鋅鎂合金薄膜,主要改變的製程參數有沉積溫度以及鎂的含量. 並藉由X光繞射,掃描式電子顯微鏡,X光能量散布圖譜,原子力顯微鏡,穿透式電子顯微鏡,光激發光圖譜以及穿透率光譜等方法量測薄膜的結構以及光學性質.
氧化鋅鎂合金薄膜於低溫沉積時具有較佳的光穿透性質,較短波長的(藍移)發光特性以及較高的鎂含量. 侷域化(區域)的效應造成試片具有特殊的光學性質. 例如由於氧化鋅鎂多層薄膜的反射引發Fabry-Perot干涉效應. 區域化的激子(exciton)以及伴隨而來的吸收係數能隙尾部延展(tail)現象,都會因為製程溫度的不同而有所變化.
當藉由改變氧化鎂以及氧化鋅濺鍍源的相對功率來提高氧化鋅鎂合金薄膜中的鎂合量時, 可以觀柴到非常特殊的薄膜微結構(microstructure). 此薄膜結構主要由底部的少量鎂摻雜氧化鋅(ZnO:Mg)薄膜, 較上方的非晶氧化鋅鎂顆粒埋在氧化鋅母相中的薄膜, 以及最上方的非晶質高鎂含量氧化鋅鎂顆粒所組成. 這種雜質析出的現象主要可以歸因於製程環境的選擇以及晶體成長時對於雜質添加所造成的晶格變形容忍度以及雜質的擴散等等因素, 因此氧化鋅鎂材料在成分及結構上可以具有幾近單晶的純氧化鋅與氧化鎂, 或者是介於兩者之間的非晶質氧化鋅鎂. 此外, 氧化鋅鎂薄膜在溫度解析的光激發光圖譜中, 激子的再結合發光能量上具有S形的發光波長特性, 這主要來自於合金薄膜中的激子侷域化(localization)所致.

MgxZn1-xO alloy deposited onto silicon wafer using sputtering. Deposition parameter varied in this process, temperature and magnesium content. Structural and optical properties studied by several characterization including, x-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, atomic force microscopy, transmission electron microscopy, photoluminescence, x-ray photoelectron microscopy and transmittance spectrum.
MgxZn1-xO alloy deposit at lower temperature have better transmittance spectrum, blue shifted emission and higher magnesium content. localization effect demonstrated in all sample lead to unique optical properties. prominent Fabry-Perot interfere rings due to multiple layer substrate reflection demonstrated in MgxZn1-xO film. localized exciton and following by enhance band tail absorption coefficient reveled in MgxZn1-xO film growth at various deposition temperature.
MgxZn1-xO film deposited with highest power ratio between MgO and ZnO demonstrated unique microstructure. The microstructure consist of bottom layer ZnO and ZnO at amorphous MgO matrix amorphous, some Mg-rich MgxZn1-xO amorphous particles also could be observed on these two layers. Due high density nucleation lead to phase separation between single crystal ZnO and cubic MgO or amorphous MgO. MgxZn1-xO film demonstrated a S-shaped photoluminescence temperature dependence of exciton recombination energy. This phenomenon is related to exciton localized in alloy-induced potential fluctuations

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