Microsoft PowerPoint - CH10CVD-3 []SiO SiO2SiO2
SiSi Si

• (STI)• (STI) • LDD/
• (PD)• (PD) • ARC < 0.25 μm
5

• Inter layer dielectric, or ILD PMD IMD
• Pre-metal dielectric : PMD – PSG
BPSG
–
• Inter-metal dielectric : IMD – USG or FSG – 400 °C
6
USGW
IMD or ILD2
ILD2
WCVD
Sidewall
8
Si (poly) SiH4 (silane)Si (poly) SiH4 (silane) Semiconductor SiCl2H2 (DCS)
Si (epi) SiCl3H (TCS) SiCl4 (Siltet)
LPCVD SiH OLPCVD SiH4, O2 SiO2 (glass) PECVD SiH4, N2O
Dielectrics PECVD Si(OC2H5)4 (TEOS), O2
LPCVD TEOSLPCVD TEOS
PECVD SiH4, N2, NH3 Si3N4 LPCVD SiH4, N2, NH3
LPCVD C8H22N2Si (BTBAS) W (Tungsten) WF6 (Tungsten hexafluoride), SiH4, H2
WSi2 WF6 (Tungsten hexafluoride), SiH4, H2 Conductors TiN Ti[N (CH3) 2]4 (TDMAT)
Ti TiCl4
• APCVD -O3-TEOS STI PMD
•
15

•
LPCVD
•
– : 0.25 2 Torr –
– 200
23 = h/w
• A: 270°, C: 90° • A • •
•
26

31

• 10 20 eV PECVD
41
–
– PMD
• LPCVD
WSi 45
46

H
•
•
• SiH SiH or SiH • , SiH3, SiH2, or SiH,
• ,
•
49
H
SiH H
H HH H
HH HH
H HC
H HC
SiH3 0.04 to 0.08
USG USG USG

0% 2.2%
Source: VLSI Technology by S M Sze 61
Source: VLSI Technology, by S.M. Sze
4×4 BPSG 850 °C4×4 BPSG 850 C, 30 , N2 30 , N2
62
etchback
• PE-TEOS
63
: 50% : 90% 87 5% 100%
64 : 87.5% : 100%
CVD
• HDP-CVD:
• USG STI
• USG FSG IMD USG FSG IMD
• PMD PMD
n1
72


α(SiO ) = 0 5×10−6 °C−1α(SiO2) = 0.5×10 6 °C 1
α(Si) = 2.5×10−6 °C−1( )
α(Si3N4) = 2.8×10−6 °C−1
α(W) = 4.5×10−6 °C−1
6 1α(Al) = 23.2×10−6 °C−1
79

• < 0.25 μm
–
– CVD
82

2 1
2

83

• (~ ) ( ) ( )1%) (78%) (20%)
•
86


1 μm planarization etchback
O TEOS O3-TEOS
• TEOS TEOS
91
SiH H
Si(OH)4

•


• PMD
103
•
• RF
• NF3
• F
• F/C 2 •
106

110

• (MW) NF3 • 99% NF • 99% NF3 •
– – –
• : – NF3 – FTIR
111
– κ C R •
– CVD • CSG (CxSiyO, κ ~ 2.5 - 3.0) α-CF (CxFy, κ ~ 2.5 – 2.7)
– (SOD) • (HSQ, κ ~ 3.0), • SOD (κ ~ 2.0 - 2.5)
112
• O2, N2O, O3
NH N • NH3 N2
• CVD CV
CF C F C F NF – CF4, C2F6, C3F8 NF3
114

115

– Ar Ar
–
ICP ECR HDP – ICP ECR: HDP
• κ
116