no treatment N2 90s
CF4 10s+N2 90s CF4 20s+N2 90s CF4 30s+N2 90s CF4 40s+N2 90s
0 2 4 6 8 10
-3 -2 -1 0 1 2 3
ln(- ln(1-f) )
Breakdown voltage (V)
no treatment CF4 10s+NH3 90s CF4 20s+NH3 90s CF4 30s+NH3 90s CF4 40s+NH3 90s NH3 90s
Fig. 3-13 The Weibull plot of the breakdown voltage HfAlOx MIS capacitor treated in (a) CF4 and N2 plasma treatment, and (b) CF4 and N2 plasma treatment.
115
Fig. 3-14 C-V frequency dispersion characteristics of the HfAlOx thin films treated in CF4 plasma for different process durations and N2 plasma for 90 sec.
Fig. 3-15 C-V frequency dispersion characteristics of the HfAlOx thin films treated in CF4 plasma for different process durations and NH3 plasma for 90 sec.
-2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 CF4 20W 10s+NH3 40W 90s
-2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 CF4 20W 20s+NH3 40W 90s
-2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 CF4 20W 10s+N2 50W 90s
-2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 CF4 20W 20s+N2 50W 90s
116
Fig. 3-16 The C-V curves before and after CVS characteristics of the HfAlOx thin films treated in CF4 plasma for different process durations and N2 plasma for 90 sec.
Fig. 3-17 The C-V curves before and after CVS characteristics of the HfAlOx thin films treated in CF4 plasma for different process durations and NH3 plasma for 90 sec.
-2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 CF4 20W 10s +NH3 40W 90s
f=50kHz CF4 20W 20s +NH3 40W 90s
f=50kHz
117 (a)
(b)
Fig. 3-18 Schottky emission plots, ln(J/T2) versus E1/2, for the HfAlOx thin film with (a) CF4 plasma + N2 plasma (b) CF4 plasma + NH3 plasma at different temperatures
1200 1250 1300 1350 1400 1450 -19
1500 1550 1600 1650 1700 1750 -20
1200 1250 1300 1350 1400 1450 -19
1650 1700 1750 1800 1850 -19
118
0 500 1000 1500 2000 2500 3000 0.0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6
q t
Fresh
N2 50W 90s
CF4 10s+N2 50W 90s CF4 20s+N2 50W 90s
E
1/2(V/cm)
1/20 500 1000 1500 2000 2500 3000 0.0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6
q t
E
1/2(V/cm)
1/2Fresh
NH3 40W 90s
CF4 10s+NH3 40W 90s CF4 20s+NH3 40W 90s
Fig. 3-19 Trapping energy levels extracted from F-P fitting for the HfAlOx samples with dual plasma treatment (a) CF4 plasma and N2 plasma (b) CF4 plasma and NH3
plasma.
119
Fig. 3-20 F-N tunneling characteristic, ln(J/E2) vs. 1/E, for the HfAlOx samples with dual plasma treatment (a) CF4 plasma and N2 plasma (b) CF4 plasma and NH3 plasma
120
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