hang hu 1, shi-jin ding 1, hf lim 1, chunxiang zhu 1, m.f. li 1, 2, s.j.kim 1, xf yu 1, jh chen 1,...
TRANSCRIPT
Hang Hu1, Shi-Jin Ding1, HF Lim1, Chunxiang Zhu1, M.F. Li1, 2,
S.J.Kim1, XF Yu1, JH Chen1, YF Yong1, Byung Jin Cho1, D.S.H.
Chan1, Subhash C Rustagi2, MB Yu2, CH Tung2, Anyan Du2, Doan
My2, PD Foo2, Albert Chin3, Dim-Lee Kwong4
1SNDL, Dept. of ECE, National Univ. of Singapore, Singapore, 2Institute of Microelectronics, Singapore,
3Dept. of Electronics Eng., National Chiao Tung Univ., Taiwan4Dept. of Electrical & Computer Eng., Univ. of Texas, Austin, TX 78712, USA
High Performance ALD HfOHigh Performance ALD HfO22-Al-Al22OO33 Laminate MIM Laminate MIM
Capacitors for RF and Mixed Signal IC ApplicationsCapacitors for RF and Mixed Signal IC Applications
Silicon Nano Device Laboratory / Dept of ECE
Outline of Presentation
Motivation
Experiment
Results and Discussion
I. RF characterization
II. DC properties
III. Reliability and lifetime
IV. High-κ MIM capacitors comparison
Conclusions
Year of Production 2003 2004 2005 2006 2007 2010 2013 2016
Analog capacitor
Density (fF/µm2) 3 3 4 4 4 7 10 15
Voltage linearity (ppm/V2)
100
Leakage (fA[pF•V] 7
RF bypass capacitor
Density (fF/µm2) 8 9 10 11 12 17 20 23
Voltage linearity (ppm/V)
1000
The International Technology Roadmap for Semiconductors, 2002 Edition
Mixed signal MIM capacitor requirement
Motivation
SiO2 and Si3N4 MIM capacitors usually provide low
capacitance density of ~1 fF/μm2.
High-k dielectrics needs to be used for future MIM
application according to ITRS roadmap.
HfO2 is a promising high-k material for MIM
capacitor. However fast oxygen diffusion.
Al2O3 have the advantage of large band gap, low
oxygen diffusivity, however only middle k value.
Motivation
4 4 μμm SiOm SiO22 deposition on Si substrate for isolation deposition on Si substrate for isolation
Bottom Bottom electrodeelectrode deposition deposition (Ta/TaN) (Ta/TaN)
Transmission line formationTransmission line formation
Dielectric depositionDielectric deposition by atomic layer deposition (ALD) by atomic layer deposition (ALD)
TEM photo of 13 nm laminate film
Experiment
Al2O3 (1nm)/HfO2 (5nm) laminate
Al2O3 as electrode contacting layers
13, 31, and 43 nm used in our work
Post deposition anneal (420Post deposition anneal (420ooC)C)
Contact hole etchingContact hole etching
TopTop metal deposition metal deposition (TaN/Al) and patterning (TaN/Al) and patterning
MIM structure Dummy device
Final Device structure for characterization
Experiment
C1
Port1 Port2RSLS2
R1 R2C2
RP
C
LS1
Cox1 Cox2
Capacitor modeling in RF regime
Equivalent circuit diagram for MIM capacitor
modeling in RF regime
I. RF capacitor model
S11
1.0
-2.0
-1.0
-0.5
0.5 2.0
1.0
0
S21
S11
1.0
-2.0-1.0
-0.5
0.5 2.01.0
0
S21
I. S-parameter simulation
Measured and simulated S-parameters for laminate
MIM capacitors by IC-CAP using SPICE3 simulator.
Measured Simulated
S11
1.0
-2.0-1.0
-0.5
0.5 2.0
1.0
0
S21
13 nm 31 nm 43 nm
0.0 5.0G 10.0G 15.0G 20.0G-300p
-200p
-100p
0
100p
200p
Sin
gle
en
ded
eff
ecti
ve c
apac
itan
ce
Frequency (GHz)
13 nm 31 nm 43 nm
Capacitive
Inductive
I. High frequency response
High frequency response of laminate MIM
capacitors from 50 MHz to 20 GHz
1k 100k 10M 1G 100G0
2
4
6
8
10
12
14
RF analysis up to 20 GHz
Cap
acit
ance
den
sity
(fF
/m
2 )
Frequency (Hz)
13 nm 31 nm 43 nm
Low frequency 1 MHz
I. Cap. versus frequency
The frequency dependence of capacitance density
of laminate capacitors (k ~19).
-2 -1 0 1 2
10-9
10-8
10-7
J (A
/cm
2 )
DC Voltage (V)
13nm 43nm
II. J-V characteristics
Typical J-V characteristics of laminate MIM capacitors
0.0 0.5 1.0 1.5 2.00.1
1
JT
/ J
RT
Voltage (V)
50C 75C 100C 125C
Leakage obtained at different temperatures for 13
nm MIM capacitor (normalized to JRT: leakage
measured at room temperature)
II. J-V characteristics
0.0 0.5 1.0 1.5 2.0
10-13
10-12
10-11
10-10
0.5 1.0 1.5-20
-18
-16
-14
-12
Ln (
J)
E1/2 (MV/cm)1/2
Schottky mechanism
J/E
(A
/V*c
m)
E1/2 (MV/cm)1/2
Poole-Frenkel mechanism
13 nm
Conduction mechanisms of 13 nm laminate MIM
capacitor, showing Pool-Frankel conduction at
high field.
II. Conduction mechanism
-2 -1 0 1 2
0.000
0.005
0.010
0.015
d
C/C
o 13nm = 1990ppm/V2; = 211ppm/V
DC Voltage (V)
Measured @1MHz
31nm = 405ppm/V2; = -95ppm/V 43nm = 207ppm/V2; = -65ppm/V
Quadratic (α) and linear (β) VCCs of laminate MIM
capacitors with thicknesses of 13, 31 and 43 nm
II. CV characteristics
4 6 8 10 12 14102
103
104
Capacitance density (fF/m2)
(p
pm
/V2 )
Thickness dependence of quadratic VCC (α) for
laminate MIM capacitors. The implication is
significant for the scaling of the high-k dielectrics.
II. CV characteristics
10k 100k 1M102
103
104
p
pm
/V2 )
Frequency (kHz)
13nm 31nm 43nm
Frequency dependence of quadratic VCC α for
laminate MIM capacitors
II. CV characteristics
0 1000 2000 3000 4000
0.88
0.90
0.92
0.94
0.96
0.98
1.00
1.02
0 1000 2000 3000 4000
1.0
1.1
1.2
1.3
1.4
/ 0
Stress Time (sec)
/ o
Stress Time (sec)
10kHz 100kHz 1MHz
Stressed @4V
Quadratic VCC as a function of stress time.
The inset shows time dependence of linear VCC .
II. CV characteristics
-350
-300
-250
2100
2200
2300
2400
0
5
10
15
20
25
30
35
Remeasured after stress stop (1hr)
Stress time @4V (1500sec)
Stress time (0sec)
(ppm/V2)
(ppm/V)
J @4V (ppmA/cm2)
Time dependence on VCCs and leakage, under
stress condition. The recovery of leakage and VCCs
may further prolong lifetime under AC condition.
II. CV characteristics
0 30 60 90 120 150 180
0
10000
20000
30000
No
rmal
ized
Cap
acit
ance
(p
pm
)
Temperature (oC)
13 nm 182 ppm/oC
31 nm 196 ppm/oC
43 nm 199 ppm/oC
TCC values for laminate MIM capacitors
with three different thicknesses
II. TCC properties
10 100 1000
1.2x10-5
1.6x10-5
2x10-5
J (A
/cm
2)
Stress time (sec)
Area=1E-4 cm2As-stressed
After 10hurs
Stressed @4V
Stress time dependence of leakage for a fresh
device up to 2000s. The device was re-stressed and
re-measured after interrupting stress for 10 hours.
III. Constant voltage stress
Life time projection of 13 nm laminate capacitor, using
50% failure time criteria, the extrapolated voltage for
10 years lifetime is 3.3 V.
III. Lifetime projection
0
20
40
60
80
100
101 102 103
Time (sec)
Cum
ulat
ive
Failu
re (%
)
Stressed @-6V Stressed @-5.8V Stressed @-5.5V
Area=1E-4cm2
0.0 1.3 2.6 3.9 5.2 6.5 7.8
0 1 2 3 4 5 6
100
102
104
106
108
1010
E (MV/cm)
Tim
e to
50%
Fai
lure
(se
c)Voltage (V)
10 years Area=1x10-4cm2
Reference [1] [2] [3] [4] [5] This work
Dielectric HfO2 (ALD) Ta2O5
AlTaOx
(PVD)Ta2O5 (CVD)
Tb doped HfO2 (PVD)
Hf/Al laminate
(ALD)
Capacitance density (fF/µm2)
13 9.2 10 9 13.3 12.8
Leakage (A/cm2)
5.7×10-7@2V 2×[email protected] 4.6×10-6@1V — 1×10-7@2V 7.45×10-9@2V
VCC607 ppm/V
853 ppm/V2 2060 ppm/V 3580 ppm/V2
2818 ppm/V2 2050 ppm/V475 ppm/V2
332 ppm/V 2667 ppm/V2
211 ppm/V 1990 ppm/V2
TCC (ppm/oC) — ~200 255 — 123 198
[1]. XF Yu et al. EDL. Vol. 24, 2003. [2]. Tsuyoshi. I et al. IEDM 2002, p.940. [3]. C. H. Huang, et al. MTT-S. 2003.[4]. Y. L. Tu. et al VLSI symp. 2003, p.79. [5]. S.J. Kim et al. VLSI symp. 2003, p.77.
IV. High-κ MIM cap. comparison
Laminate capacitor is among one of the best for RF
capacitor application.
Conclusions
High performance HfOHigh performance HfO22/Al/Al22OO33 laminate MIM capacitors laminate MIM capacitors
have been demonstrated for the first time.have been demonstrated for the first time.
The ALDThe ALD laminate MIM capacitors exhibit high C laminate MIM capacitors exhibit high C
density, superior dielectric stability up to 20 GHz, density, superior dielectric stability up to 20 GHz,
low leakage current, and promising reliability.low leakage current, and promising reliability.
For 13For 13 nm nm laminate laminate MIM capacitor MIM capacitor
C density C density ~12.8~12.8 fF/ fF/μμmm22 up to 20 Gup to 20 GHzHz
~ 2~ 21111 ppm/V ppm/V,,
Leakage ~ Leakage ~ 7.45 n7.45 nA/cmA/cm22 at at 2 V2 V
Meets Meets all requirements for RF bypassall requirements for RF bypass ccapacitorapacitor
Acknowledgment
This work was supported by Institute of
Microelectronics (Singapore) under Grant
R-263-000-233-490 and the National
University of Singapore under Grant R-263-
000-221-112.