표제지

목차 3

Ⅰ. 서론 5

Ⅱ. 문헌연구 9

2.1 ITO 박막의 중요성 9

2.2 ITO의 결정구조 및 상평형 10

2.2.1 결정구조 10

2.2.2 상평형 15

2.3 ITO 박막의 특성 15

2.3.1 전기적 특성 15

2.3.2 광학적 특성 19

2.4 ITO 박막의 성장 20

2.4.1 스퍼터의 원리 20

2.4.2 핵생성 23

2.4.3 박막성장 26

2.4.3.1 박막성장기구 27

2.4.3.2 박막구조모델 30

2.4.3.3 Structure zone model 32

2.5 Sputter증착 박막 제작시 공정변수의 영향 38

2.5.1 인가전력 38

2.5.2 공정압력 39

2.5.3 기판온도 40

2.5.4 산소분압 41

2.5.5 타겟밀도 42

2.5.6 열처리 42

Ⅲ. R.F-마그네트론 스퍼터링 법으로 제조한 ITO 박막에 대한 공정변수의 영향 44

3.1 서론 44

3.2 실험방법 45

3.3 결과 및 토의 57

3.3.1 공정압력 및 인가전력 57

3.3.2 기판온도 및 열처리 80

3.3.3 산소분압 및 타겟조성, PC기판 112

3.4 결론 127

Ⅳ. 비가열 기판상의 ITO 박막 결정화 128

Ⅴ. 가열기판 및 비가열 기판에 증착한 ITO 박막의 결정화 거동 148

Ⅵ. ITO 박막의 우선배향 및 특성 171

Ⅶ. 종합결론 189

Ⅷ. 참고문헌 192

그림목차 12

Fig. 2-1. ITO crystal structure : Bixbyite structure or C-type rare earth structure 12

Fig. 2-2. Lattice parameter of Sn-doped In2O3 ceramics measured by X-ray and neutron diffraction 13

Fig. 2-3. Summary of experimental results on phase equilibria in the In2 O3-SnO2 pseudo-binary system 16

Fig. 2-4. Reported (1970-2000) resistivities of binary transparent conducting oxide materials(line : oxide △, □, ● : doped oxide) 18

Fig. 2-5. The number of target atoms(or molecules) ejected per incidention 21

Fig. 2-6. The physical effect of primary ion bombardment and sputtering 22

Fig. 2-7. Processes in the nucleation and growth of crystals on a substrate 24

Fig. 2-8. Regimes of nucleation and growth 24

Fig. 2-9. Schematic of the stages of film growth 28

Fig. 2-10. Three mechanisms of thin film growth 29

Fig. 2-11. Structure development under vactors condition[57] 31

Fig. 2-12. Structural zone model 33

Fig. 2- 13. Schematic representation of sputtered- film structures showing the superposition of shadowing, surface- diffusion, and bulk diffusion processes that establish structural zones [57] 36

FIg. 2-14. Schematic images of the cross-sectional microstructure of ITO flms deposited 37

Fig. 3-1. Fabrication procedure of ITO thin film 46

Fig. 3-2. Schematic diagram of the RF-magnetron sputtering system 47

Fig. 3-3. Particles size distribution and SEM micrographs of powers. (a) In2O3 (b) SnO2. 49

Fig. 3-4-1. Four point probe method for measuring sheet resistance 56

Fig. 3-4-2. Thin film conductor with length l, width w, and thickness d 56

Fig. 3-5. X-ray diffraction profiles of ITO thin films deposited as a function of deposition time at RF-power 50W 58

Fig. 3-6. X-ray diffraction profiles of ITO thin films deposited as a function of working pressure at RF-power 50W for 20min 60

Fig. 3-7. Change of substrate temperature as a function of deposition time and working pressure at RF-power 50W 60

Fig. 3-8-1. X-ray diffraction profiles of ITO thin films deposited as a function of deposition time at working pressure 20mTorr and RF-power 25W 61

Fig. 3-8-2. X-ray diffraction profiles of ITO thin films deposited as a function of deposition time at working pressure 20mTorr and RF-power 50W 61

Fig. 3-8-3. X-ray diffraction profiles of ITO thin films deposited as a function of deposition time at working pressure 20mTorr and RF-power 75W 62

Fig. 3-8-4. X-ray diffraction profiles of ITO thin films deposited as a function of deposition time at working pressure 20mTorr and RF-power 100W 62

Fig. 3-9. X-ray diffraction profiles of ITO thin films deposited as a function of substrate distance at RF-power 50W, working pressure 10mTorr and deposition time 20min 63

FIg. 3-10. SEM photographs of thin films deposited at working pressure 20mTorr and RF-power 50W 65

FIg. 3-11. Cross-sectional view of thin films deposited at working pressure 20mTorr and RF-power 50W 66

Fig. 3-12. SEM photography of thin films deposited at working pressure SmTorr for 80min 67

Fig. 3-13. SEM phothgraphy of thin films deposited at RF-power 50W 10min 69

FIg. 3-14. SEM photography of thin films deposited at RF-power 50W for 10min 70

Fig. 3-15. SPM photography of thin films deposited at RF-power 50W for 80min 71

Fig. 3-16. Sheet resistance of ITO thin films deposited as a function of deposition time at RF-power 50W 72

Fig. 3-17. Sheet resistance of ITO thin films deposited as a function of deposition time at working pressure 5mTorr 72

Fig. 3-18. Thickness of ITO thin films deposited as a function of deposition time at RF-power 50W 74

Fig. 3-19. Resistivity of ITO thin films deposited as a function of deposition time at RF-power 50W 74

Fig. 3-20. Sheet resistance and resistivity of ITO thin films as a function of deposition time under RF-power 50W and working pressure of 10 mTorr 76

Fig. 3-21-1. Transmittance of ITO thin films deposited as a function of working pressure at RF-power 50W for 5min 77

Fig. 3-21-2. Transmittance of ITO thin films deposited as a function of working pressure at RF-power 50W for 10min 77

Fig. 3-21-3. Transmittance of ITO thin films deposited as a function of working pressure at RF-power 50W for 20min 78

Fig. 3-21-4. Transmittance of ITO thin films deposited as a function of working pressure at RF-power 50W for 40min 78

Fig. 3-21-5. Transmittance of ITO thin films deposited as a function of working pressure at RF-power 50W for 80min 79

Fig. 3-22. Transmittance of ITO thin films deposited as a function of deposition time at working pressure 5mTorr and RF-power 50W 79

Fig. 3-23-1. X-ray diffraction profiles of ITO thin films deposited as a function of deposition time at RF-power 50W, working pressure 5mTorr and room temperature 81

Fig. 3-23-2. X-ray diffraction profiles of ITO thin films deposited as a function of deposition time at RF-power 50W, working pressure 5mTorr and in-situ 100c 81

Fig. 3-23-3. X-ray diffraction profiles of ITO thin films deposited as a function of deposition time at RF-power 50W, working pressure 5mTorr and in-situ 200℃ 82

Fig. 3-23-4. X-ray diffraction profiles of ITO thin films deposited as a function of deposition time at RF-power 50W, working pressure 5mTorr and in-situ 100℃ 82

Fig. 3-23-5. X-ray diffraction profiles of ITO thin films deposited as a function of deposition time at RF-power 50W, working pressure 5mTorr and in-situ 400℃ 83

Fig. 3-24. (400)HWFM of ITO thin films deposited as a function of deposition time at RF-power 50W, working pressure 5mTorr and substrate temperature 400℃ by in-situ process 83

Fig. 3-25. X-ray diffraction profiles of ITO thin films deposited as a function of substrate temperature at RF-power 50W, working pressure 5mTorr for 80min 85

Fig. 3-26. (400)FWHM of ITO thin films deposited as a function of substrate temperature at RF-power 50W, working pressure 5mTorr for 80min 85

Fig. 3-27. X-ray diffraction profiles of ITO thin films deposited at RF-power 25W, working pressure 10mTorr and deposition time 10min and heated in variable atmosphere at 300℃ for 1 hour 86

Fig. 3-28. X-ray diffraction profiles of ITO thin film heat treated at 300℃ for 1 hour, and ITO thin films deposited at RF-power 25W, working pressure 10mTorr, without heat treatment and in-situ heat treatment and at 300℃ for 20min 86

Fig. 3-29. X-ray diffraction profiles of ITO thin films deposited as a function of deposition time at RF-power 25W, working pressure 10mTorr 88

FIg. 3-30-1. SEM phothgraphs of thin films deposited at room temperature working pressure 5mTorr and RF-power 50W 90

Fig. 3-30-2. Cross-sectional view of thin films depositer at room temperature working pressure 5mTorr and RF-power 50w 91

Fig. 3-31-1. SEM phothgraphs of thin films deposited at 300c working pressure 5mTorr and RF-power 50W 92

Fig. 3-31-2. Cross-sectional view of thin films deposited at 300c working pressure 5mTorr and RF-power 50W 93

FIg. 3-32-1. SEM photographs of thin films deposited for 5min at working pressure 5mTorr and RF-power 50W 94

Fig. 3-32-2. SEM photographs of thin films deposited for 40min at working pressure 5mTorr and RF-power 50W 95

Fig. 3-32-3. Cross-sectional view of thin films deposited for 40min at working pressure 5mTorr and RF-power 50W 96

Fig. 3-33. SPM photographs of thin films deposited for 80min as a function of substrate temperature at working pressure 5mTorr and RF-power 50W 98

Fig. 3-34. RMS of ITO thin films deposited for 80min as a function of substrate temperature at RF-power 50W and working pressure 5mTorr 99

Fig. 3-35. SEM photographs of thin films deposited at working pressuer 5mTorr and RF-power 25W for 80min 101

Fig. 3-36. Sheet resistance of ITO thin films deposited as a function of at working pressure 5mTorr and RF-power 50W 102

Fig. 3-37. Thickness of ITO thin films as functions of deposition time and temperature. Films were deposited at RF-power 50W and working pressure 5mTorr 104

Fig. 3-38. Resistivity of ITO thin films as functions of deposition time and temperature. Films were deposited at RF-power 50W and working pressure 5mTorr 104

Fig. 3-39-1. Transmittance of ITO thin films deposited for 5min as a function of substrate temperature at working pressure 5mTorr, RF-power 50W 106

Fig. 3-39-2. Transmittance of ITO thin films deposited for 10min as a function of substrate temperature at working pressure 5mTorr, RF-power 50W 106

Fig. 3-39-3. Transmittance of ITO thin films deposited for 20min as a function of substrate temperature at working pressure 5mTorr, RF-power 50W 107

Fig. 3-39-4. Transmittance of ITO thin films deposited for 40min as a function of substrate temperature at working pressure 5mTorr, RF-power 50W 107

Fig. 3-39-5. Transmittance of ITO thin films deposited for 80min as a function of substrate temperature at working pressure 5mTorr, RF-power 50W 108

Fig. 3-40-1. Transmittance of ITO thin films deposited as a function of deposition time at room temperature, working pressure 5mTorr and RF-power 50W 108

Fig. 3-40-2. Transmittance of ITO thin films deposited as a function of deposition time at 100℃, working pressure 5mTorr and RF-power 50W 109

Fig. 3-40-3. Transmittance of ITO thin films deposited as a function of deposition time at 200℃, working pressure 5mTorr and RF-power 50W 109

Fig. 3-40-4. Transmittance of ITO thin films deposited as a function of deposition time at 300℃, working pressure 5mTorr and RF-power 50W 110

Fig. 3-40-5. Transmittance of ITO thin films deposited as a function of deposition time at 400℃, working pressure 5mTorr and RF-power 50W 110

Fig. 3-41. Bandgap energy of ITO thin films deposited as functions of deposition time and temperature at working pressure 5mTorr and RF-power 50W 111

Fig. 3-42-1. X-ray diffraction profiles of ITO thin films deposited as a function of deposition time at working pressure 10mTorr, RF-power 50W and Ar:O2 = 4:1 sccm 113

Fig. 3-42-2. X-ray diffraction profiles of ITO thin films deposited as a function of deposition time at working pressure 10mTorr, RF-power 50W and Ar:O2 = 3:2 sccm 113

Fig. 3-42-3. X-ray diffraction profiles of ITO thin films deposited as a function of deposition time at working pressure 10mTorr, RF-power 50W and Ar:O2 = 2:3 sccm 114

Fig. 3-43. X-ray diffraction profiles of ITO thin films deposited for 80min as a function of Ar and O2 ratios at working pressure 10mTorr, RF-power 50W 114

Fig. 3-44. (222)/(440) peak intensity ratios of ITO thin films deposited for 80min as a function of Ar and O2 ratios at working pressure 10mTorr, RF-power 50W 115

Fig. 3-45. Sheet resistance of ITO thin films as a function of deposition time at RF-power 50W, working pressure of 10mTorr and Ar:O2 = 2:3 sccm 115

Fig. 3-46. SEM imafe if ITO thin films deposited for 80min as a function od Ar and O2 ratios at working pressure 10mTorr, RF-power 50W 118

Fig. 3-47. Transmittance of ITO thin films deposited on (a) glass substrate and (b) PC substrate as a function of deposition time at working pressure 5mTorr and RF-power 75W 119

Fig. 3-48. X-ray diffraction profiles of ITO thin films deposited on (a) glass substrate and (b) PC substrate as a function of deposition time at working pressure 5mTorr and RF-power 75W 121

Fig. 3-49. SPM photofrapgs of films deposited on PC substrate for 80min as a function of RF-power at working pressure 5mTorr 122

Fig. 3-50. SPM phorographs of thin films deposited for 80min on (a) glass substrate and (b) PC substrate at working 123

Fig. 3-51. Transmittance of ITO thin films deposited on (a) glass substrate and (b) PC substrate as a function of deposition time at working pressure 5mTorr and RF-power 75W 124

Fig. 3-52-1. X-ray diffraction peak profiles of ITO targets 125

Fig. 3-52-2. Shift down of (440) peak as the content of Sn increased 125

Fig. 3-53. SEM image of surface droplts and nodules on an ITO sputter target 126

Fig. 4-1. SEM micrographs of thin deposited as a function time for (a) 5 and (b) 10 min at RF-power 50W, working pressure 10mTorr 131

Fig. 4-2. SEM micrographs of thin films deposited as a function of deposition time for (a) 10 (b) 20 (c) 40 and (d) 80 min at RF-power 50W, working pressure 10mTorr 132

Fig. 4-3. Cross-sectional view of thin films deposited as a function of deposirtion time for (a) 10 (b) 20 (c) 40 and (d) 80 min 133

Fig. 4-4. Thickness of ITO thin films deposited as a function of deposition time 134

Fig. 4-5. Mean grain size of thin films deposited as a function of deposition time 134

Fig. 4-6. X-ray diffraction profiles of ITO thin films as a function of deposition time for (a) 5 (b) 20 (c) 40 and (d) 80 min 136

Fig. 4-7. Change of substrate temperature measured at the back of substrate using a tharmocoulpe as a function of deposition time 136

Fig. 4-8. X-ray diffraction profiles of ITO thin films deposited by (a) 1 min sputtering repeated 40 times (b) 2 min sputtering repeated 20 times (c) 5 min sputtering repeated 8 times with a cooling interval of 10min and (d) 40 min continuous sputtering 139

Fig. 4-9. SEM micrographs of ITO thin films deposited by (a) 1 min sputtering repeated 40 times (b) 2 min sputtering repeated 20 times (c) 5 min sputtering repeated 8 times with a cooling interval of 10 min and (d) 40 min continuous sputtering 140

Fig. 4-10. Transmittance of intermittently and continuously deposited thin films with the total deposition time of 40min 141

Fig. 4-11. X-ray diffraction profiles of in-situ heat treated ITO thin films at 300℃ for (a) 5 and (b) 10 min 144

Fig. 4-12. TEM bright field images of ITO films deposited (a) with and (b) without external heating 145

Fig. 5-1. X-ray diffraction profiles of ITO thin films deposited as function of the deposition time (a) 5. (b) 10. (c) 20. (d) 40 and (e) 80 min 153

Fig. 5-2. FWHM of XRD (400)peaks of ITO films deposited at room temperature and 200℃ 154

Fig. 5-3. SEM micrograpghs of thin films deposited at room temperature as a function of the deposition time (a) 5 (b) 10 (c) 20 and (d) 40 min 155

Fig. 5-4. SEM micrographs of thin films deposited at 200c as a function of the deposition time (a) 5. (b) 10. (c) 20 and (d) 40 min 156

Fig. 5-5. Cross-sectional view of thin films deposited at room temperature as a function of the deposition time (a) 5 (b) 10 (c) 20 and (d) 40 min 160

Fig. 5-6. Cross-sectional view of thin films deposited at 200c as a function of the deposition time (a) 5 (b) 10 (c) 20 and (d) 40 min 161

Fig. 5-7. TEM images of ITO thin films deposited for 20min at room temperature 162

Fig. 5-8. TEM images of ITO thin films deposited for 20min at 200c 163

Fig. 5-9. Surface view of the suggested crystallization model in ITO thin films as the deposition time increased 164

Fig. 5-10. Cross-sectional view of the suggested crystallization model in ITO thin films as the deposition time increased 165

Fig. 5-11. Variation of hall mobility and carrier concentration as a function of deposition time at RF-power 50W and working pressure 5mTorr 166

Fig. 5-12. Resistivity of ITO thin films deposited at room temperature and 200℃ as a function of deposition time under RF-power 50W and working pressure 10 mTorr 167

Fig. 5-13. Sheet resistance of ITO thin films deposited at room temperature and 200℃ as a function of deposition time under RF-power 50W and working pressure 10 mTorr 168

Fig. 5-14. Transmittance of ITO thin films deposited as a function of deposition time under RF-power 50W and working pressure 5mTorr 169

Fig. 6-1. X-ray diffraction patterns of ITO thin films deposited for 80min as a function of oxygen flow rate at RF-power 50W, working pressure 10mTorr 174

Fig. 6-2. X-ray diffraction patterns of ITO thin films as a function of deposition time (a) 5 (b)10 (c) 20 (d) 40 and (e) 80min at RF-power 25W, working pressure 10mTorr(Ar:O2=2:3sccm) 174

Fig. 6-3. X-ray diffraction patterns of ITO thin films deposited for 80min as a function of RF-power (a) 25 (b) 50 (c) 75 and (d) 100 W at working pressure 5mTorr 175

Fig. 6-4. X-ray diffraction patterns of ITO thin films as a function of deposition time (a) 5 (b) 10 (c) 20 (d) 40 and (e) 80 min at RF-power 50W and working pressure 10mTorr 175

Fig. 6-5. X-ray diffraction patterns of ITO thin films as a function of working pressure of (a) 5, (b) 10, (c) 20 and (d) 40 mTorr 176

Fig. 6-6. X-ray diffraction patterns of ITO thin films as a function of deposition time (a) 5 (b) 10 (c) 20 (d) 40 and (e) 80 min 176

Fig. 6-7. X-ray diffraction patterns of ITO thin films as a function of deposition time (a) 5 (b) 10 (c) 20 (d) 40 and (e) 80 min at RF-power 50W, working pressure 5mTorr and substrate temperature 300℃ 177

Fig. 6-8. (a) Three dimensional AFM (b) top image of SEM and (c) cross sectional view of SEM image of (222) oriented ITO thin film 180

Fig. 6-9. (a) Three dimensional AFM (b) top image SEM and (c) cross sectional view of SEM image of (400) oriented ITO thin film 181

FIg. 6-10. (a) Three dimensional AFM (b) tom image of SEM and (c) cross sectional view of SEM image of (400) oriented ITO thin film 182

FIg. 6-11. (a) Three dimensional AFM (b) tom image of SEM and (c) cross sectional view of SEM image of (622) oriented ITO thin film 183

Fig. 6-12. SEM and SPM image of (222), (400), (440), and (622) oriented ITO thin films 184

Fig. 6-13. Transmittance of ITO thin films with (222), (400), (440), (622) preferred orientations 185

표목차 50

Table 3-1. Characteristics of raw material powders 50

Table 3-2. Density of targets 51

Table 3-3. Properties of Corning 1737 glass and poly carbonate 52

Table 3-4. The deposition condition for ITO thin film 53

Table 4-1. Optical transparency and resistivity of the films deposited intermittently with different sputtering methods 146

Table 6-1. Characteristics of ITO thin films 186

Table 6-2. Generation conditions and properties of ITO thin film with (222), (400), (440), (622) preferred orientations 187