1

Chapter 7

2

CVD

3

CVD PVD

4

? ?

5

?

6

() ()

ni = ne ()

= ne/(ne + nn)

ne:ni:

nn:

7

0.01% (High density plasma ,HDP) 15%

~100%

8

()

9

(Radio frequency, RF)

10

11

e- + A A+ + 2 e-

12

13

e- + A A* + e-

A* A + h ()

14

15

h

h

h:

:

16

e- + AB A + B + e-

CVD

17

A B

e-

B

e-A

18

()

CF4 (F)

e + CF4 CF3 + F + e

4F + SiO2 SiF4 + 2O

19

CVD ()

PECVDSiH4 N2O ()e + SiH4 SiH2 + 2H + e

e + N2O N2 + O + e

SiH2 + 3O SiO2 + H2O PECVD

20

21

(Mean Free Path, MFP)

n21

=

n

22

MFP

(a) ( b)

23

(MFP)

:

, MFP

, MFP

1p

24

Q & A

?

(760 Torr)MFP

25

me

26

RF

27

(Thermal Velocity)

v = (kTe / me)1/2

RF , Te 2 eVve 5.93107 cm/sec = 1.33107 mph

28

:F = qvB

(Gyro-motion)

29

30

mqB=

31

= v/

v

32

, E

f(E)

2 - 3 eV

,

:200 - 400C

33

34

, PECVD

35

(Sheath Potential)+-+-+-+-+-+-+

+-+-+-+-+-+-+

+-+-+-+-+-+-+

+-+-+-+-+-+-+

+-+-+-+-+-+-+

+-+-+-+-+-+-+

+-+-+-+-+-+-+

+-+-+-+-+-+-+

+-+-+-+-+-++

++-+-+-+-++

++-+-+-+++

+++-+-+++

+++-++++

+++++++

Vp

Vf

x

36

(flux)

37

38

Vol

t

39

RF

0

0

RF

RF

40

13.56MHz

41

()

Vp = 10 20 V

42

()

0

43

()

V2

A2

A1

V1/V2 =(A2/A1)4

V1 (V1-V2)

44

45

IC : PECVD(CVD)

CVD

46

CVD

47

PECVD LPCVD

LPCVD (150 mm) PECVD (150 mm)

SiH4+ O 2 SiO2 + SiH4+ N2O SiO2 +

p =3 Torr, T=400 C p=3 Torr, T=400 C and

RF=180 W

100 to 200 /min 8000 /min

48

HDP-CVD

49

HDP CVD

0.25 m, 4:1

50

51

PECVD

CVD:

: ,

52

PECVD

1-10 Torr 1020 eV

53

PECVD

RF

54

(RF ): 200 to 1000 eV (): 10 to 20 eV

55

(E-chuck)

56

(< 100 mTorr) MFP,

57

58

59

60

CVD

61

O2 H2O

/

62

H2O, O2

OO H

H2O, CO2,

O O OH H

63

LOCOS STI

64

CVD

()

NF3

65

NF3

F FF

F N2N2F

CVD

N2, SiF4,

66

CVD (RPCVD)

, SiO2, SiON, and Si3N4(High-): TiO2, and

Ta2O5 PMD

67

MFP

CVD //

68

(mTorr)

MFP

69

70

ICP and ECR

(Inductively coupled plasma, ICP) (Transformer coupled plasma,

TCP)

(Electron cyclotron resonance, ECR)( mTorr)

71

(ICP)

72

(ICP)

73

74

ICP

75

(ECR)

(Gyro-frequency) (cyclotron frequency)

mqB=e

76

(ECR)

MW = e,

77

ECR

B

78

ECR

ECR

79

ECR

80

n = n+

MFP

81

PECVD

ICP ECR