Transcript Radiation Tolerance of a 0.18 mm CMOS Process

Radiation Tolerance
of a 0.18 mm CMOS Process
M. Manghisonic,d, L. Rattia,c, V. Reb,c, V. Spezialia,c
a Università di Pavia, Dipartimento di Elettronica, 27100 Pavia, Italy
b Università di Bergamo, Dipartimento di Ingegneria, 24044 Dalmine, Italy
c INFN, Sezione di Pavia, Pavia 27100, Italy
d Studio di Microelettronica, STMicroelectronics, 27100 Pavia, Italy
7th International Conference on
Advanced Technology and Particle Physics
Villa Olmo, 15-19 October 2001
V.Re, "Radiation Tolerance of a 0.18 mm CMOS Process"
Outline
Submicron CMOS technologies and their
radiation hardness
Static, signal and noise characterization of irradiated
NMOS and PMOS devices belonging to a 0.18 mm
process
Comparison with NMOS and PMOS transistors
belonging to a 0.35 mm technology
7th International Conference on Advanced Technology and Particle Physics, Villa Olmo, 15-19 October 2001
V.Re, "Radiation Tolerance of a 0.18 mm CMOS Process"
Submicron CMOS technologies
High density mixed-signal front-end systems for high
granularity detectors (microstrip, pixel)
Reduced thickness of the
gate oxide:
0.35 mm: tOX=7.2 nm
0.25 mm: tOX=5.5 nm
0.18 mm: tOX=4 nm
Improved radiation
hardness
Present focus: 0.25 mm CMOS
Characterization of the following CMOS generation
(0.18 mm)
7th International Conference on Advanced Technology and Particle Physics, Villa Olmo, 15-19 October 2001
V.Re, "Radiation Tolerance of a 0.18 mm CMOS Process"
Test and irradiation conditions
0.18 mm CMOS process by ST Microelectronics
Standard open structure layout (no special radiation
hard technique)
Irradiation up to 100 kGy (10 Mrad) with a 60Co
source
Devices biased during irradiation at normal
operating conditions
7th International Conference on Advanced Technology and Particle Physics, Villa Olmo, 15-19 October 2001
V.Re, "Radiation Tolerance of a 0.18 mm CMOS Process"
Static characterization: ID-VGS
NMOS W/L=2000mm/0.35mm @ V =0.8 V
DS
1
ID [mA]
10
Before irradiation
100 kGy
-1
10
-3
10
-5
10
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
0.6
V [V]
GS
7th International Conference on Advanced Technology and Particle Physics, Villa Olmo, 15-19 October 2001
V.Re, "Radiation Tolerance of a 0.18 mm CMOS Process"
Threshold voltage
PMOS: decrease of
less 10 mV in Vth after a
NMOS W=2000mm
0.42
100 kGy dose
0.4
PMOS W=2000mm
-0.41
L=1.00
0.39
L=1.00
L=0.50
20
40
60
80
Dose [kGy]
NMOS: Vth drop of about
10 mV after a 100 kGy dose
100
th
0.38
0
L=0.50
-0.42
V [V]
th
V [V]
0.41
-0.43
-0.44
0
20
40
60
Dose [kGy]
7th International Conference on Advanced Technology and Particle Physics, Villa Olmo, 15-19 October 2001
80
100
V.Re, "Radiation Tolerance of a 0.18 mm CMOS Process"
Signal parameters: transconductance
NMOS W/L=2000mm/0.35mm @ V =0.8 V
40
8
Before irradiation
100 kGy
30
m
20
6
4
Before irradiation
100 kGy
2
10
0
0
DS
10
g [mA/V]
gm [mA/V]
PMOS W/L=200mm/0.50mm @ V =0.8 V
DS
50
0.25
0.5
0.75
1
ID [mA]
1.25
1.5
1.75
2
0
0
0.4
0.8
1.2
I [mA]
D
7th International Conference on Advanced Technology and Particle Physics, Villa Olmo, 15-19 October 2001
1.6
2
V.Re, "Radiation Tolerance of a 0.18 mm CMOS Process"
Noise characterization:
noise voltage spectra
NMOS W/L=2000mm/0.35mm @ I =0.25mA
D
100
Small changes over the
entire frequency interval
after irradiation
10
PMOS W/L=2000mm/0.35mm @ I =0.5mA
1
D
100
0.18 mm process
4
10
5
10
6
10
7
10
Frequency [Hz]
Model of the noise power spectral
density
a Af
4
kT
+
S (f ) =
gm
f
2
n
N
0.1
1000
Before irradiation
100 kGy
e [nV/Hz1/2]
N
1/2
e [nV/Hz ]
Before irradiation
100 kGy
10
1
0.1
1000
10
4
10
5
10
6
Frequency [Hz]
7th International Conference on Advanced Technology and Particle Physics, Villa Olmo, 15-19 October 2001
10
7
V.Re, "Radiation Tolerance of a 0.18 mm CMOS Process"
Noise characterization: white noise
NMOS W=2000mm @ I =0.5mA; V =0.8V
D
1.3
DS
Very low radiation sensitivity
of the white noise
1.25
L=1.00
L=0.50
1.15
1.1
1.05
PMOS W=2000mm @ I =0.5mA; V =-0.8V
D
1.5
1
DS
L=1.00
0.95
L=0.50
1.4
20
40
60
80
Dose [kGy]
The increase in white noise is
never larger than 15% (it is
very small in PMOS devices)
100
1/2
0
N
0.9
e [nV/Hz ]
N
1/2
e [nV/Hz ]
1.2
L=0.35
1.3
1.2
1.1
1
0
20
40
60
Dose [kGy]
7th International Conference on Advanced Technology and Particle Physics, Villa Olmo, 15-19 October 2001
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100
V.Re, "Radiation Tolerance of a 0.18 mm CMOS Process"
Noise characterization: 1/f noise
NMOS W=2000mm @ I =0.5mA
D
20
L=1.00
L=0.70
Although to a limited extent, 1/f
noise is affected by irradiation
L=0.50
L=0.35
12
PMOS W=2000mm @ I =0.5mA
8
D
10
L=1.00
4
8
0
20
40
60
80
100
f
Dose [kGy]
The Af parameter increases less
than a factor of 2
L=0.50
L=0.35
6
-14
2
0
A [10 V ]
f
-13
2
A [10 V ]
16
4
2
0
0
20
40
60
Dose [kGy]
7th International Conference on Advanced Technology and Particle Physics, Villa Olmo, 15-19 October 2001
80
100
0.18 mm process vs 0.35 mm process
Threshold Voltage
NMOS W/L=2000mm/1.00mm
0.7
PMOS W/L=2000mm/1.00mm
-0.2
0.35 um process
0.18 um process
-0.4
V [V]
0.5
th
th
V [V]
0.6
0.4
-0.6
-0.8
0.35 um process
0.18 um process
0.3
-20
0
20
40
60
Dose [kGy]
80
100
120
-1
0
20
40
60
Dose [kGy]
80
100
0.18 mm process vs 0.35 mm process
NMOS W/L=2000mm/1.00mm @ V =0.8 V
DS
Before irradiation
100 kGy
-1
I [mA]
10
1
2
10
0
10
-2
10
-4
NMOS W/L=2000mm/1.00mm @ V =0.8 V
DS
Before irradiation
100 kGy
D
D
I [mA]
10
10
10
-3
0.18 um process
-5
10
-0.2
0.35 um process
-6
0
0.2
V
GS
[V]
0.4
0.6
10
-0.2
0
0.2
V
GS
[V]
0.4
0.6
0.18 mm process vs 0.35 mm process
PMOS W/L=2000mm/0.70mm @ I =0.25mA
PMOS W/L=2000mm/0.70mm @ I =0.25mA
D
100
Before irradiation
100 kGy
10
N
1/2
e [nV/Hz ]
N
1/2
e [nV/Hz ]
Before irradiation
100 kGy
1
10
1
0.35 um process
0.18 um process
0.1
1000
4
10
D
100
5
10
6
10
Frequency [Hz]
7
10
0.1
1000
4
10
5
10
Frequency [Hz]
6
10
7
10
0.18 mm process vs 0.35 mm process
Noise voltage spectrum
NMOS W/L=2000mm/0.70mm @ I =0.25mA
NMOS W/L=2000mm/0.35mm @ I =0.25mA
D
100
D
100
Before irradiation
100 kGy
e [nV/Hz ]
1/2
10
N
N
1/2
e [nV/Hz ]
Before irradiation
100 kGy
1
10
1
0.35mm process
0.18 mm process
0.1
1000
4
10
5
10
Frequency [Hz]
6
10
7
10
0.1
1000
4
10
5
10
Frequency [Hz]
6
10
7
10
V.Re, "Radiation Tolerance of a 0.18 mm CMOS Process"
Conclusions
Static and noise characterization under irradiation of
submicron N and P-channel MOSFETs has been performed
The investigated devices exhibited a good radiation tolerance
up to 100 kGy absorbed dose of ionizing radiation
The intrinsic radiation hardness of submicron CMOS
processes has been confirmed
7th International Conference on Advanced Technology and Particle Physics, Villa Olmo, 15-19 October 2001