Vacuum Level. Fermi Level. W f W Bottom of conduction. (a) Vacuum Level. Fermi Level e - W W. X1= X2 (b) (c)

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1 E Vacuum Level Fermi Level W f W 0 W Bottom of conduction (a) Met Vacuu Vacuum Level E Fermi Level e - W W W X1= X2 (b) Tunneling Phenomenon (c) Fig. 1.1 Energy diagrams of vacuum-metal boundary: (a) without external electric field, (b) with an external electric field, and (c) Tunneling phenomenon [76]. 42

2 (a) (b) Fig. 1.2 (a) Simulation of the equipotential lines of the electrostatic field [77], (b) Field amplification factor B as a function of the onset field [76]. 43

3 (a). (b) (c) (d) (e) Fig. 1.3 (a) CRT (Cathode Ray Tube), (b) VFD (Vacuum Fluorescent Display), (c) PDP (Plasma Display Panel), and (d)(e) FED (Field Emission Display). 44

4 (a) (b) (c) (d) (e) (f) Fig. 1.4 (a) Sony portable DVD player using a Candescent field emission display [16], (b) Motorola 15 field emission display [16], (c) Motorola 5.6 color FED, (d) Pixtech 5.6 color FED, (e) Futaba 7 color FED, and (f) 7 color CNT FED from Samsung. 45

cylinder in the nanotube assembly. (a) (b) (c) Fig. 2.

5 (a) (b) Fig. 2.1 High-resolution transmission electron microscopy images of (a) single-walled nanotubes (SWNTs) and (b) multiwalled nanotubes (MWNTs). Every layer in the image (fringe) corresponds to the edges of each cylinder in the nanotube assembly. (a) (b) (c) Fig. 2.2 Illustrations of the atomic structure of (a) an armchair, (b) a ziz-zag nanotube, (c) The Stonne-Wales transformation occurring in an armchair nanotube under axial tension. 46

unit vectors a1, a2 and the chiral angle with respect to the zigzag axis, (b)

tubules, including zigzag, armchair, and chiral tubules, (c) Schematic diagram

(a) (b) (c) (d) 5 (a) Schematic diagram of an arc evaporator, (b) Schematic of the

6 Fig. 2.4 (a) The chiral vector OA is defined on the honeycomb lattice of carbon atoms by unit vectors a1, a2 and the chiral angle with respect to the zigzag axis, (b) Possible vectors specified by the pairs of integers (n,m) for general carbon tubules, including zigzag, armchair, and chiral tubules, (c) Schematic diagram showing how a hexagonal sheet of graphite is rolled to form a carbon nanotube. (a) (b) (c) (d) Fig. 2.5 (a) Schematic diagram of an arc evaporator, (b) Schematic of the laser ablation process, (c) Schematic of the thermal chemical vapor deposition, (d) Schematic of the microwave plasma enhanced chemical vapor deposition (MPECVD) [39][40][46]. 47

7 (a) (b) (c) Fig. 2.6 (a) hydrocarbon dissociate & deposit carbon on surface, (b) carbon diffuses through solid metal, and (c) carbon precipitates as curved graphitic layers [78]. Fig. 2.7 Influence of the metal-support interaction on the mode of filamentous for (a) base growth (root growth) mode, (b) tip growth mode [53][54], and (c) Combined tip growth and base growth [59]. 48

8 Fig. 3.1 Experimental procedures flow charts 49

9 Fig. 3.3 (a)~(c) High density plasma post treatment for diode device Fig. 3.2 (a)~(h) Fabrication procedure of the carbon nanotubes for diode structure field emission device 50

10 51

11 Fig. 3.4 Fabrication procedure of the carbon nanotubes insulated gate structure field emission device (a)~(p). Fig. 3.5 High density plasma post treatment for triode device (a)~(c) 52

12 Fig. 3.6 Experimental procedure by Thermal CVD process 53

13 (a) (b) Fig. 3.7 Schematic of emission measurement for (a) diode type and (b) triode type 54

14 Pre-treatment conditions Temperatures : 700 Temperatures : 700 Table 3-1 Conditions of different pretreatment time and catalyst layer thickness. thickness Catalyst Thickness (Å) time Pretreatment time (minutes) 5 10 A2 B2 C2 D2 Table 3-2 Conditions of C 2 H 4 flow rate for CNTs growth lengths (700 ). temperature Growth Temperature gas E2 C 2 H 4 (sccm) 40 E4 100 E7 138 E8 55

15 Table 3-3 Conditions of Ar or/and mixture O 2 gas HDPPT for diode (without Bias power). power gas 10sccm Ar gas 20sccm 30sccm 40sccm 5sccm O 2 gas 10sccm 15sccm Ar Ar and O 2 mixture gas (20sccm) + O 2 (10sccm) Table 3-4 Conditions of Ar or/and O 2 mixture gas HDPPT for diode with Bias power (fixed ICP power 300W). power gas Ar gas 20sccm O 2 gas 10sccm Ar Ar and O 2 mixture gas (20sccm) + O 2 (10sccm) 56

16 (a) (b) (d) 57

17 Nano-particle sizes CNTs length 40 Nano-particle sizes Catalyst metal thickness (e) CNTs length Catalyst metal Nano-particle CNTs length thickness sizes (f) Fig. 4.1 Effects of pretreatment 15min for different catalyst layer thickness (a) 50Å, (b) 75Å, (c) 100Å, (d) 150Å, (e) plot of average nanoparticle size and CNT length as a function the Fe-Ni thickness (pretreatment temperature 700 ), and (f) catalyst metal thickness versus nanoparticle size and CNT lengths. 58

Fe-Ni Fe-Ni-C (f) (a) (b) (c) (d) Fig. 4.

18 Fe-Ni Fe-Ni-C (f) (a) (b) (c) (d) Fig. 4.2 Effects of CH 4 on pre-treatment for CNT growth (a) without CH 4, (b) with CH 4 (200sccm)(C 2 H 4 =20sccm, 500, 15minutes), (c) without CH 4, (d) with CH 4 (200sccm)(C 2 H 4 =20sccm, 700, 15minutes). 59

19 (a) (b) 60

20 (c) (d) Fig. 4.3 Effects of CNTs growth (a) without N 2, (b) with N 2, (c) TEM image for bamboo-like CNTs, and (d) bamboo-like CNTs mechanism [74]. 61

21 (a) C 2 H 4 : 20sccm (b) C 2 H 4 : 50sccm (c) C 2 H 4 : 70sccm (d) C 2 H 4 : 138sccm 62

22 35 30 CNTs Lengths(um) H degrees I degrees J degrees C 2 H 4 (sccm) (e) C 2 H 4 Growth Temperature flows (f) Fig. 4.4 SEM images for different C 2 H 4 flow rate ) 20sccm, (b) 50sccm, (c) 70sccm, (d) 138sccm, (e) effects of different growth temperature versus C 2 H 4 flow rate and (f) summary experimental results for CNT lengths and different growth temperature. 63

23 (a) (b) (c) (d) (e) (f) Fig. 4.5 TEM images for growth mechanism on thermal CVD (a) base growth, (b)(c) with/without the catalyst on base growth, (d)(e) tip growth, and (f) catalyst metal inside. 64

24 (a) (b) ions decomposite more radicals Physical and Chemical Etching reactions of radical on the surface byproduct desorption (c) Fig. 4.6 (a) Physical mechanism, (b) chemical mechanism, and (c) combined physical and chemical mechanism. 65

25 (a) (b) (c) (d) 66

-8-10 -12-14 -16-18 -20-22 -24-26 F-N Plot : Ar 10sccm 60sec PPT for different ICP power 250W 300W 400W 500W 0.0 0.1 0.2 0.3 0.4 0.

26 F-N Plot : Ar 10sccm 60sec PPT for different ICP power 250W 300W 400W 500W /E (e) Raman spectra of Ar 10sccm 60sec for different ICP power 250W 300W 400W 500W Intensity(a.u.) 250W 300W 400W 500W Wavenumber(cm -1 ) (f) Ar 10sccm 60sec PPT for different ICP power F-N Plot : Ar 10sccm 60sec PPT for different ICP power -8 Emission Current Density(A/cm 2 ) E-3 1E-4 ln(j/e 2 ) 250W 300W 400W 500W ln(j/e 2 ) W 300W 400W 500W -26 1E Application Field(E)(v/um) 1/E (g) (h) Sample number Condition Turn on field E (V/um) (@J=10uA/cm 2 ) Current density J (ma/cm 2 ) (@E=5 v/um) Field enhancement factor (ß) a. As-grown b. 250W c. 300W d. 400W e. 500W (i) Fig. 4.7 SEM images of CNTs post-treatment by Ar 10sccm 60sec for different ICP power of (a), (b) 250W, (c) 300W, (d) 400W, (e) 500W, (f ) Raman spectra of CNTs, (g) field emission curve J-E, (h) F-N plot, and (i) summary experimental results. 67

27 (a) (b) (c) (d) 68

-8-10 -12-14 -16-18 -20-22 -24 F-N Plot : Ar 20sccm 60sec PPT for different ICP power as-growth 250W 300W 400W 500W -26 0.0 0.1 0.2 0.3 0.4 0.

) 250W 300W 400W 500W 1000 1200 1400 1600 1800 2000 Wavenumber(cm -1 ) (f) Ar 20sccm 60sec PPT for different ICP power -8 F-N Plot : Ar 20sccm 60sec PPT for different ICP power Emission Current

28 F-N Plot : Ar 20sccm 60sec PPT for different ICP power as-growth 250W 300W 400W 500W /E (e) Raman spectra of Ar 20sccm 60sec for different ICP power 250W 300W 400W 500W Intensity(a.u.) 250W 300W 400W 500W Wavenumber(cm -1 ) (f) Ar 20sccm 60sec PPT for different ICP power -8 F-N Plot : Ar 20sccm 60sec PPT for different ICP power Emission Current Density J (A/cm 2 ) E-3 1E-4 ln(j/e2) as-growth 250W 300W 400W 500W ln(j/e2) as-growth 250W 300W 400W 500W 1E Application Field E (v/um) /E (g) (h) Sample number Condition Turn on field E (V/um) (@J=10uA/cm 2 ) Current density J (ma/cm 2 ) (@E=5 v/um) Field enhancement factor (ß) a. As-grown b. 250W c. 300W d. 400W e. 500W (i) Fig. 4.8 SEM images of CNTs post-treatment by Ar 20sccm 60sec for different ICP power of (a), (b) 250W, (c) 300W, (d) 400W, (e) 500W, (f ) Raman spectra of CNTs, (g) field emission curve J-E, (h) F-N plot, and (i) summary experimental results. 69

29 (a) (b) (c) (d) 70

-8-10 -12-14 -16-18 -20-22 -24-26 0.0 0.1 0.2 0.3 0.4 0.

0.01 1E-3 1E-4 1E-5 ln(j/e 2 ) 250W 300W 400W 500W 1/E 250W 300W 400W 500W 0 1 2 3 4 5 6 7 Application Field E (v/um) ln(j/e 2 ) -10-12 -14-16 -18-20 -22-24 -26 250W 300W 400W 500W 0.0 0.1 0.2 0.3 0.

30 (e) Ar 30sccm 60sec PPT for different ICP power F-N Plot : Ar 30sccm 60sec PPT for different ICP power -8 F-N Plot : Ar 30sccm 60sec PPT for different ICP power Emission Current Density J (A/cm 2 ) E-3 1E-4 1E-5 ln(j/e 2 ) 250W 300W 400W 500W 1/E 250W 300W 400W 500W Application Field E (v/um) ln(j/e 2 ) W 300W 400W 500W /E (f) (g) Sample number Condition Turn on field E (V/um) (@J=10uA/cm 2 ) Current density J (ma/cm 2 ) (@E=5 v/um) Field enhancement factor (ß) a. As-grown b. 250W c. 300W d. 400W e. 500W (h) Fig. 4.9 SEM images of CNTs post-treatment by Ar 30sccm 60sec for different ICP power of (a), (b) 250W, (c) 300W, (d) 400W, (e) 500W, (f ) field emission curve J-E, (g) F-N plot, and (h) summary experimental results. 71

31 (a) (b) (c) (d) 72

32 (e) Ar 40sccm 60sec PPT for different ICP power F-N Plot : Ar 40sccm 60sec PPT for different ICP power -8 F-N Plot : Ar 40sccm 60sec PPT for different ICP power Emission Current Density J (A/cm 2 ) E-3 1E-4 1E-5 ln(j/e 2 ) 250W 300W 400W 500W 1/E 250W 300W 400W 500W Application Field E (v/um) ln(j/e 2 ) W 300W 400W 500W /E (f) (g) Sample number Condition Turn on field E (V/um) (@J=10uA/cm 2 ) Current density J (ma/cm 2 ) (@E=5 v/um) Field enhancement factor (ß) a. As-grown b. 250W c. 300W d. 400W e. 500W (h) Fig SEM images of CNTs post-treatment by Ar 40sccm 60sec for different ICP power of (a), (b) 250W, (c) 300W, (d) 400W, (e) 500W, (f ) field emission curve J-E, (g) F-N plot, and (h) summary experimental results. 73

33 (a) (b) (c) (d) 74

34 Intensity(a.u) Wavenumber(cm -1 ) BIAS 50W BIAS 100W BIAS 150W (e) Ar 20sccm ICP 300W 60sec PPT for different BIAS power F-N Plot : Ar 20sccm ICP 300W 60sec PPT for different BIAS power F-N Plot : Ar 20sccm ICP 300W 60sec PPT for different BIAS power -8 Emission Current Density(A/cm 2 ) E-3 1E-4 ln(j/e 2 ) Bias 0W Bias 50W Bias 100W Bias 150W 1/E Bias 0W Bias 50W Bias 100W Bias 150W ln(j/e 2 ) Bias 0W Bias 50W Bias 100W Bias 150W -26 1E Application Field(E)(v/um) 1/E (f) (g) Sample number BIAS Condition Turn on field E (V/um) (@J=10uA/cm 2 ) Current density J (ma/cm 2 ) (@E=5 v/um) Field enhancement factor (ß) (h) Fig SEM images of CNTs post-treatment by Ar 20sccm ICP power 300W 60sec for different BIAS power of (a) 0W, (b) 50W, (c) 100W, (d) 150W, (e) Raman spectra of CNTs, (f) field emission curve J-E, (g) F-N plot, and (h) summary experimental results. 75

35 (a) (b) (c) (d) 76

-8-10 -12-14 -16-18 -20-22 -24-26 F-N Plot : O 2 5sccm 60sec PPT for different ICP power O 2 250W O 2 300W O 2 400W O 2 500W 0.0 0.1 0.2 0.3 0.4 0.

) 40 30 20 10 0 1000 1200 1400 1600 1800 2000 Wavenumber(cm -1 ) (f) O 2 5sccm 60sec PPT for different ICP power F-N Plot : O 2 5sccm 60sec PPT for different ICP power -8 Emission Current

36 F-N Plot : O 2 5sccm 60sec PPT for different ICP power O 2 250W O 2 300W O 2 400W O 2 500W /E (e) O2 5sccm 250W 60sec O2 5sccm 300W 60sec O2 5sccm 400W 60sec O2 5sccm 500W 60sec Intensity(a.u.) Wavenumber(cm -1 ) (f) O 2 5sccm 60sec PPT for different ICP power F-N Plot : O 2 5sccm 60sec PPT for different ICP power -8 Emission Current Density(A/cm 2 ) E-3 1E-4 ln(j/e 2 ) O 2 250W O 2 300W O 2 400W O 2 500W ln(j/e 2 ) O 2 250W O 2 300W O 2 400W O 2 500W -26 1E Application Field(E)(v/um) 1/E (g) (h) Sample number Condition Turn on field E (V/um) (@J=10uA/cm 2 ) Current density J (ma/cm 2 ) (@E=5 v/um) Field enhancement factor (ß) a. As-grown b. 250W c. 300W d. 400W e. 500W (i) Fig SEM images of CNTs post-treatment by O 2 5sccm 60sec for different ICP power of (a), (b) 250W, (c) 300W, (d) 400W, (e) 500W, (f ) Raman spectra of CNTs, (g)field emission curve J-E, (h) F-N plot, and (i) summary experimental results. 77

37 (a) (b) (c) (d) 78

0.01 1E-3 1E-4 1E-5 ln(j/e 2 ) O 2 250W O 2 300W O 2 400W O 2 500W 1/E O 2 250W O 2 300W O 2 400W O 2 500W 0 1 2 3 4 5 6 7 Application Field(E)(v/um) ln(j/e 2 ) -10-12 -14-16 -18-20 -22-24 -26 O 2

38 (e) O 2 10sccm 60sec PPT for different ICP power F-N Plot : O 2 10sccm 60sec PPT for different ICP power -8 F-N Plot : O 2 10sccm 60sec PPT for different ICP power Emission Current Density(A/cm 2 ) E-3 1E-4 1E-5 ln(j/e 2 ) O 2 250W O 2 300W O 2 400W O 2 500W 1/E O 2 250W O 2 300W O 2 400W O 2 500W Application Field(E)(v/um) ln(j/e 2 ) O 2 250W O 2 300W O 2 400W O 2 500W /E (f) (g) Sample number Condition Turn on field E (V/um) (@J=10uA/cm 2 ) Current density J (ma/cm 2 ) (@E=5 v/um) Field enhancement factor (ß) a. As-grown b. 250W c. 300W d. 400W e. 500W (h) Fig SEM images of CNTs post-treatment by O 2 10sccm 60sec for different ICP power of (a), (b) 250W, (c) 300W, (d) 400W, (e) 500W, (f ) field emission curve J-E, (g) F-N plot, and (h) summary experimental results. 79

39 (a) (b) (c) (d) 80

0.01 1E-3 1E-4 ln(j/e 2 ) O 2 250W O 2 300W O 2 400W O 2 500W 1/E O 2 250W O 2 300W O 2 400W O 2 500W ln(j/e 2 ) -10-12 -14-16 -18-20 -22-24 O 2 250W O 2 300W O 2 400W O 2 500W -26 1E-5 0 1 2 3 4 5 6

40 (e) O 2 20sccm 60sec PPT for different ICP power F-N Plot : O 2 20sccm 60sec PPT for different ICP power F-N Plot : O 2 20sccm 60sec PPT for different ICP power -8 Emission Current Density(A/cm 2 ) E-3 1E-4 ln(j/e 2 ) O 2 250W O 2 300W O 2 400W O 2 500W 1/E O 2 250W O 2 300W O 2 400W O 2 500W ln(j/e 2 ) O 2 250W O 2 300W O 2 400W O 2 500W -26 1E Application Field(E)(v/um) 1/E (f) (g) Sample number Condition Turn on field E (V/um) (@J=10uA/cm 2 ) Current density J (ma/cm 2 ) (@E=5 v/um) Field enhancement factor (ß) a. As-grown b. 250W c. 300W d. 400W e. 500W (h) Fig SEM images of CNTs post-treatment by O 2 20sccm 60sec for different ICP power of (a), (b) 250W, (c) 300W, (d) 400W, (e) 500W, (f ) field emission curve J-E, (g) F-N plot, (h) summary experimental results. 81

41 (a) (b) (c) (d) 82

42 BIAS 50W BIAS 100W BIAS 150W 240 Intensity(a.u) Wavenumber(cm -1 ) (e) O 2 10sccm ICP 300W 60sec PPT for different BIAS power F-N Plot : O 2 10sccm ICP 300W 60sec PPT for different BIAS power F-N Plot : O 2 10sccm ICP 300W 60sec PPT for different BIAS power -8 Emission Current Density(A/cm 2 ) E-3 1E-4 1E-5 ln(j/e 2 ) BIAS 50W BIAS 100W BIAS 150W 1/E Jorig J50 J100 J Application Field(E)(v/um) ln(j/e 2 ) LNorig1 LN501 LN1001 LN /E (f) (g) Sample number BIAS Condition Turn on field E (V/um) (@J=10uA/cm 2 ) Current density J (ma/cm 2 ) (@E=5 v/um) Field enhancement factor (ß) a. 0W b. 50W c. 100W d. 150W (h) Fig SEM images of CNTs post-treatment by O 2 10sccm ICP power 300W 60sec for different BIAS power of (a) 0W, (b) 50W, (c) 100W, (d) 150W, (e ) Raman spectra of CNTs, (f) field emission curve J-E, (g) F-N plot, and (h) summary experimental results. 83

43 (a) (b) (c) 84

44 F-N Plot : Ar 20sccm and O 2 10sccm mixture gas without/with Bias power without Bias power with Bias power /E Ar 20sccm and O 2 10sccm mixture gas without/with Bias power F-N Plot : Ar 20sccm and O 2 10sccm mixture gas without/with Bias power -8 Emission Current Density(A/cm 2 ) E-3 1E-4 1E-5 ln(j/e 2 ) without Bias power with Bias power Application Field(E)(v/um) ln(j/e 2 ) without Bias power with Bias power /E (d) (e) Sample number BIAS Condition Turn on field E(V/um) (@J=10uA/cm 2 ) Current density J(mA/cm 2 ) (@E=5 v/um) Field enhancement factor (ß) a. No PPT b. without Bias c. With Bias (f) Fig SEM images of CNTs post-treatment by Ar 20sccm and O 2 10sccm mixture gas ICP power 300W 60sec for BIAS power of (a) no PPT, (b) without Bias power, (c) with Bias power 100W, (d)field emission curve J-E, (e) F-N plot, and (f) summary experimental results. 85

45 (a) (b) (c) (d) 86

46 Ar HDPPT O2 HDPPT Anode current I a (ua) Application gate voltage V g (v) (e) Sample number Condition Turn on voltage Emission Current (ua) (@V=50 v) a. b. Ar (20sccm) O 2 (10sccm) (f) Fig SEM images of CNTs post-treatment for PPT (a) triode structure, (b), (c) Ar 20sccm for ICP power 300W 60sec, (d) O 2 10sccm for ICP power 300W 60sec, (e) field emission curve I-V, and (f) summary field emission results. 87

47 Table 4-1 Comparison physical versus chemical plasma etching. Etch Parameter Etch Mechanism Physical etch (RF field perpendicular to wafer surface) Physical ion sputtering Physical etch (RF field parallel to wafer surface) Radicals in plasma reacting with wafer surface Chemical etch Radical in liquid reacting with wafer surface Combined Physical and Chemical In dry etch, etching includes ion sputtering and radicals reacting with wafer surface Sidewall Profile Anisotropic Isotropic Isotropic Anisotropic to isotropic Selectivity Poor/difficult to Fair/good Good/excellent Fair/good increase Etch Rate High Moderate Low Moderate Table 4-2 Shows effects of changing plasma etch parameters. Increased( ) or Decrease( ) in Etch Control Parameters RF Frequency RF Power DC BIAS Electrode Size Ion Energy DC BIAS Etch Rate Selectivity Physical Etch 88

48 Table 4-3 Summary Ar and O 2 HDPPT for different flow rates VS different ICP Powers on turn-on field, emission current density, and field enhancement factor. ß 89

49 Table 4-4 Summary Ar and O 2 HDPPT for different BIAS Powers on turn-on field, emission current density, and field enhancement factor ß 90

Arcing prevention by dry clean optimization at Shallow Trench Isolation (STI) Etch in AMAT MxP by use of plasma parameters

Page 1 Arcing prevention by dry clean optimization at Shallow Trench Isolation (STI) Etch in AMAT MxP by use of plasma parameters www.tu-cottbus.de www.infineon.com 2 nd AEC/ Conference Europe, April 18