마그네트론 자기장 구조를 가진 전자 싸이크로트론 공명 플라즈마를 이용한 고플럭스 중성 입자빔 발생에 관한 연구 : High Flux Hyperthermal Neutral Beam Generation using Electron Cyclotron Resonance Plasmas with Magnetron Magnetic Field Configuration

다국어 초록 (Multilingual Abstract)

Hyperthermal neutral beams (HNB) represent a viable means of overcoming the problems of material processing. HNB etching, HNB nitridation, HNB oxidation, and HNB assisted thin film deposition have been studied and noticeable results have been reported. The key issue with HNB sources is the production of high flux HNBs. Several type HNB sources were developed but high HNB flux at a substrate was not yet achieved.
The purpose of this thesis was to generate high flux HNBs on a substrate. Four studies in this thesis were carried out. First, requirements for high flux HNB generation were theoretically specified. Second, the ECR HNB source with magnetron magnetic field configuration (MMC) was developed and the ECR plasma of the ECR HNB source was characterized using a Langmuir probe, optical emission spectroscopy, and an ion energy analyzer. The results confirmed that the ECR HNB source satisfied the requirements for high flux HNB generation. Third, the ECR HNB source with race track magnetic field configuration (RMC) was developed in an effort to solve the problems of the ECR HNB source with MMC. The ECR plasma of the ECR HNB source with RMC was characterized using a Langmuir probe. HNB energy distributions were obtained from fitting the ion kinetic energy distributions in Gaussian curves. Finally, the ECR HNB source with RMC was applied for GaN epitaxial growth at low substrate temperature. The atomic structure and the thickness of the GaN thin film were investigated using SEM, SIMS, and TEM. The HNB flux at a substrate was obtained from the results.
This thesis contributed to increasing HNB flux at a substrate more than 1*10^15 /cm^2s and to measurements of HNB energy distribution and HNB flux. In addition, single crystalline GaN layers were grown at low substrate temperature using the HNBs produced by the ECR HNB source.

목차 (Table of Contents)

• Chapter 1 Introduction 1
• Chapter 2 Physics of High Flux HNB Generation 4
• 2.1 Surface neutralization 4
• 2.2 Requirements for high flux HNB generation 5
• Chapter 3 ECR HNB Source with Magnetron Magnetic Field Configuration 10
• 3.1 Type 3 HNB source with ICP 10
• 3.2 Design of ECR HNB source with MMC 12
• 3.2.1 Feature of ECR HNB source with MMC 12
• 3.2.2 ECR heating 14
• 3.2.3 Electron confinement 17
• 3.2.4 Angular distribution of impinging ions on neutralization plate 20
• 3.3 Electron temperature measurement 22
• 3.3.1 Experimental setup 22
• 3.3.2 Langmuir probe method 24
• 3.3.3 He I line intensity ratio method 27
• 3.3.4 Results and discussions 28
• 3.4 Ion density measurement 30
• 3.5 Plasma potential measurement 32
• 3.5.1 Experimental setup 32
• 3.5.2 Relation between broadening of IED and plasma potential 33
• 3.6 Summary 41
• Chapter 4 ECR HNB Source with Race Track Magnetic Field Configuration and Measurements of HNB Energy Distributions 42
• 4.1 Introduction 42
• 4.2 Design of ECR HNB source with RMC 44
• 4.3 Characteristics of ECR plasma 48
• 4.3.1 Experimental setup 48
• 4.3.2 Image of the ECR plasma 49
• 4.3.3 Results and discussions 51
• 4.4 HNB energy distribution 57
• 4.4.1 Ionizer 57
• 4.4.2 Experimental setup 59
• 4.4.3 Results and discussions 60
• 4.5 Summary 66
• Chapter 5 Nitrogen HNB Assisted GaN Epitaxial Growth at Low Substrate Temperature and Measurements of the Absolute Flux of Nitrogen HNBs 67
• 5.1 Introduction 67
• 5.2 Experimental setup 70
• 5.3 GaN growth procedures 78
• 5.4 Depth profile and atomic structure of GaN thin film 79
• 5.5 Measurement of the absolute flux of nitrogen HNBs 83
• 5.6 Summary 85
• Chapter 6 Conclusions and Further Studies 86
• References 91