In the present study, we synthesized HfO2/NiO thin films on Si (100) substrates. The first layer of NiO thin films was synthesized on silicon substrates using radio frequency magnetron sputtering deposition (RFMSD) technique at the various deposition times of 10, 20, 30, 40, and 50 minutes. The layer of HfO2 thin films was synthesized on NiO/Si substrate using hot filament metal vapor deposition (HFMVD) technique for 5 minutes. The morphology and the thickness of HfO2 and NiO thin films can be determined by Field emission scanning electron microscope (FESEM). The crystallines of HfO2 and NiO thin films were examined by X-ray diffraction (XRD). The elemental composition or compound of HfO2 and NiO thin films have been investigated using X-ray photoelectron spectroscopy. Each sample of HfO2/NiO/Si substrate has tested to check the resistive switching which was investigated by an I-V loop method.

Table of Contents
Abstract i
Acknowledgement ii
Table of Contents iv
List of Tables vi
List of Figures vviii
List of Equations x
Chapter 1 Introduction 1
1.1Nickel oxide 2
1.2 Hafnium dioxide 3
1.3 Resistivity switching principle 4
1.3.1 Structure and operation of device 5
1.4 Motivation 7
Chapter 2 Synthesis and characterization technique 9
2.1 Experimental method 9
2.1.1 RF Magnetron sputter deposition technique 9
2.1.2 Hot filament metal vapor deposition (HFMVD) 11
2.1.3 Synthesis of NiO on Silicon 12
2.1.4 Synthesis of HfO2 on NiO/Si substrate 13
2.1.5 Synthesis HfO2/NiO on silicon p-type substrate 15
2.2 Characterization technique 16
2.2.1 Field emission scanning electron microscopy 17
2.2.2 X-ray Diffraction (XRD) 20
2.2.3 X-ray photoelectron spectroscopy 21
2.2.4 Resistivity switching (I-V Measurement) 23
Chapter 3 Results and Discussions 25
3.1 Morphological characterization 25
3.2 X-ray diffraction analysis 28
3.3 X-ray photoelectron spectroscopy (XPS) analysis 31
3.4 Resistivity switching (I-V measurement) 33
3.4.1 Resistivity switching of NiO layers 34
3.4.2 Resistivity switching of HfO2/NiO layers 38
Chapter 4 Conclusion 43
References 45

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