ZnO / MoO3超晶格結構在177℃下利用原子層沉積系統（Atomic Layer Deposition）沉積在a面藍寶石基板上。接著分別在磁場為0Tesla, 3Tesla, 6Tesla與9Tesla時量測溫度範圍為15K~300K時樣品的電阻(RT)，並使用熱活化能公式進行計算與分析其電性結果。根據電性模擬結果表示，在氧化鋅與氧化鉬超晶格結構中存在著四個中間能隙，每個能隙在每個溫度下的貢獻度都可以被描述。此外，這些中間能隙是由於磁矩而和磁場有關，遵循公式為E(B)=E(0)-mB。另一方面，也可利用熱熱活化能量能公式計算出Log(T)-Log(μ)。在0磁場下，遷移率對溫度的關係呈現出兩個不同的斜率且在50K到300K之間其斜率和T-1.44相關¬，這是由於晶格散射的關係。最後，分別在300K、200K、150K、100K、50K、10K下量測MR曲線。10K下的MR是正磁阻且與磁場平方有關，而較高溫度下的MR呈現雜訊的情況，是由於高溫下四個能階在導電上都有貢獻，而E4貢獻正磁阻，E1、E2、E3貢獻了負磁阻導致互相抵銷的情況發生。

Superlattices of ZnO/MoO3 have been prepared by atomic layer deposition (ALD) on a-oriented sapphire substrates at 177 oC. The electrical properties were studied via measurement of resistivity as a function of temperature (T) from T=15 K to 300 K and magnetic field (B). The superlattice structures comprise multiple periods of ZnO/MoO3 bilayers that are hoped to incur new physical properties not seen in their pristine form. Data analysis by brute-force data fitting based on thermally activated processes of band conduction resulted largely in four midgap states responsible for the measured functional dependence of resistivity on T and B. Except for the shallowest state that is at 5 meV from the band edge, the other three states consistently follow the linear relation of E(B)=E(0)-mB over the whole studied temperature range, hence demonstrate negative magnetoresistance. The shallowest state, follows a positive B-square dependence in revelation of a cyclotron effect for free carriers moving along a spiraling path. The countering magnetoresistive behaviors make the magnetoresistance exceedingly small and difficult to measure. Analysis of the charge carrier mobilities, according to the simple power law of temperature, suggest that impurity charge scattering and lattice vibration scattering mechanisms are both at play.

論文審定書 i
Acknowledgment ii
摘要 iii
Abstract iv
Figures vi
Tables vii
I. Introduction 1
II. Experimental details: Measurements and Analysis 4
III. Result and discussion 5
IV. Conclusion 15
References 17
Appendices 22
A.Suitable Temperature and Substrate for ZnO and MoO3 22
B.Initial Layer of ZnO/MoO3 superlattices 23
C.Structural properties of ZnO/MoO3 superlattices 24
D.Optical properties 26
E.Sputtered ZnO+SLs 27
F.Chemical formula of MoO3 form from different precursor 28
G.Database related to the crystal structures 29

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