過渡金屬二碲化物 (XTe2) 顯示出過渡金屬的新特性。當X是過渡金屬，例如 Pt，而碲化後所形成的PtTe2會是狄拉克半金屬並且表現出無質量的狄拉克費米子以及高電子遷移率。當 X 是Cr，而碲化後所形成的CrTe2是本徵二維鐵磁金屬，具有巨大的反常霍爾效應。然而我們所生長的樣品是在常溫且薄膜的形式下也能夠擁有此性質。因此，我們研究CrTe2、PtTe2、PtTe2/CrTe2 和 Pt1-xCrxTe2合金的生長以及特性。我們這次的目的是成功地生長二維 CrPtTe2 薄膜並對其進行特性的分析。為此，我們必須建立一套穩定的生長技術，在單晶基板上磊晶薄膜。首先，我們必須先使用e-beam進行 Cr、Pt、CrPt 的超薄 (< 5 nm) 金屬薄膜/合金生長，再通過RTA的方法將薄膜進行熱處理，最後再通過常壓化學氣相沉積 (APCVD) 在惰性氣體中進行碲化以獲得二維二硫屬化物化合物。成功合成後，通過一系列分析技術進行進一步特性分析，以清楚地觀察結構、振動、樣貌和磁性。

Transition metal ditellurides (XTe2) show new properties based on transition metal types. For example, if X is a transition metal, such as Pt, then PtTe2 transforms into Dirac semimetals exhibiting massless Dirac fermions and high mobility, when X is Cr, then CrTe2 is an intrinsic two-dimensional ferromagnetic metal with a huge anomalous Hall effect. However, the samples we grew can have this property at room temperature and in the form of thin films. Therefore, we study the growth and properties of CrTe2¬, PtTe2, PtTe2/CrTe2 and Pt1-xCrxTe2 alloys. Our goal this time is to successfully grow two-dimensional CrPtTe2 thin films and analyze their properties. To this end, we must establish a set of stable growth techniques to epitaxial thin films on single crystal substrates. First, we must first use e-beam for ultra-thin (< 5 nm) metal film/alloy growth of Cr, Pt, CrPt, then heat the film by RTA, and finally using atmospheric pressure chemical vapor deposition (APCVD) in an inert gas for tellurization heat treatment to obtain two-dimensional dichalcogenide compounds. Once successfully synthesized, further characterization was performed through a range of analytical techniques to clearly observe structure, vibration, morphology, and magnetism.

Verification letter from the oral examination committee......................................... i
中文摘要....................................................................................................................... ii
Abstract....................................................................................................................... iii
Table of content...........................................................................................................iv
List of Figures...............................................................................................................v
List of Tables………………………………………………………………………... vi
Chapter 1.Introduction1
1.1Definition and thin film growth of transition metal dichalcogenides1
1.2Characteristic of PtTe2 and CrTe2 samples2
Chapter 2.Experimental Method4
2.1The introduction of the experiment4
2.1.1Platinum sputter4
2.1.2Dual e-beam evaporator5
2.1.3High-temperature furnace (APCVD system)6
2.1.4Scanning electron microscope (SEM)8
2.1.5Rapid thermal annealing (RTA)9
2.1.6Raman spectrometer9
2.1.7High-resolution x-ray diffraction (HRXRD) spectroscope11
2.1.8Superconducting quantum interference device (SQUID)13
2.1.9X-ray photoelectron spectroscopy (XPS)15
2.2Sample growth information16
2.2.1Single layer film series (series A)16
2.2.2Trilayer (series B) and bilayer (series C) film series20
2.2.3Alloy film series (series D)25
Chapter 3.Results And Discussion28
3.1Series A: Single layer CrTe2 and PtTe228
3.1.1PtTe2 measurement28
3.1.1.1Raman measurement28
3.1.1.2XRD (ϴ-2ϴ) measurement34
3.1.2CrTe2 measurement35
3.1.2.1SEM measurement35
3.1.2.2Raman measurement37
3.1.2.3XRD (ϴ-2ϴ) measurement40
3.2Series B: Trilayer tellurization after Pt/Cr/Pt41
3.2.1PtTe2/CrTe2/PtTe2 measurement41
3.2.1.1SEM measurement41
3.2.1.2Raman measurement44
3.2.1.3XRD (ϴ-2ϴ) measurement50
3.2.1.4SQUID measurement51
3.3Series C: Bilayer tellurization after Cr/Pt (Japan Pt)53
3.3.1CrTe2/PtTe2 measurement53
3.3.1.1SEM measurement53
3.3.1.2Raman measurement55
3.3.1.3XRD (ϴ-2ϴ) measurement58
3.4Series D: CrPt alloy thin films after CrPt alloy tellurization60
3.4.1CrPtTe2 measurement60
3.4.1.1SEM measurement60
3.4.1.2Raman measurement62
3.4.1.3XRD (ϴ-2ϴ) measurement65
3.4.1.4XPS measurement68
3.4.1.5SQUID measurement74
Chapter 4.Conclusion76
References77
Appendix81

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