Presentation - Virtual Inductor Library: a new inductor design approach

Virtual Inductor Library :
a new inductor design approach
Alfred H. C. Tseng Ph.D.
UMC/CRD_Logic/MM&RF

Outline
� Virtual Inductor Library Implementation by
EM Design Methodology (EMDM)
� Results and Comparison
� Other Applications by using EMDM
� Conclusions
2

How to Do Inductor Design ?
� At first, referenced to foundry’s measured
inductor library and scalable model library.
� Designers iterate the following processes:
� Designing test structures
� Wafer processing
� Measuring data
� Modeling
� If not satisfied, do again …
“Time Time and Money are losing”
losing
3

UMC’s Innovative Approach
- EM Design Methodology (EMDM)
� In addition to existed measured and
scalable model library.
� We provide some extra features:
� This “methodology” is to generate a process
related information for EM simulator, then
customers can design their own innovative
inductors with fast; accurate; and low-cost
features.
� Save prototype & test cycle-time.
� Reduce R&D cost.
4

UMC’s EMDM
- What is our approach ?
� General Inductor Design
With real Si measured data
3-D EM simulation data
+ RF SPICE model
3-D EM simulation to interpolate,
then to output S-parameter
3-D EM simulation to extrapolate,
then to output S-parameter
Parameter 2
Inductor Pool
Parameter 1
*** Parameters : Di; W; S & N
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UMC’s EMDM
- What is our approach ?
�Customer’s Special Inductor Design
Novel Inductor
Design
Pattern ground
shielding
3-D EM
Simulation
Transformer or Stacked
S-Parameter Designer
6

UMC’s EMDM: Work Flow
Working Flow
UMC Process
Technology profile
SiO2
Si
M3
M1
M2
2
ε
Testkey Layout
Wafer
Fabrication
ICCAP
Parameter Extraction
3-D EM Simulation Circuit Simulation
S-Parameter
Ansoft HFSS
Ansoft Designer
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RF SPICE
Model

UMC’s EMDM
- What is the technology file?
ε r
ε r
ε r
ε r
Conductivity
Passivation
Thickness
M6 Thickness
SiO 2 Thickness
M5 Thickness
SiO 2 Thickness
Silicon
Thickness
Last Metal
Second Top Metal
8

UMC’s EMDM
- What is the technology file?
Material Physic Param Source
Substrate T.K, Rs EDR
STI T.K, Dielectrics EDR
M1~6 T.K, Rs EDR
ILD/IMD1~5 T.K, Dielectrics EDR
Passivation T.K, Dielectrics EDR
*** This unique technology file has been proved by comparing
the simulation data with real silicon measured data.
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EMDM’s Inductor Design Flow
All you need is to input geometric parameters:
N Turns
D Diameter
W Width
S Spacing
T Top Metal thickness
Seg Segments (ex. Octagonal, Circular)
“A A friendly interface to designers.”
designers.
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Virtual Inductor Library by EMDM
� For general inductor design, both real Si
measurement data and 3D EM simulation data are
used for the model extraction.
� Since combining these two groups of raw data, we
can extract RF SPICE model with higher accuracy.
� This unique technology file can be faithfully
represented Si process parameters.
� Based on this calibrated technology file, designers
can implement their novel ideas, then obtain Sparameter
for circuit simulation.
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Ansoft HFSS
� Current version 9.0.
� A true 3D electromagnetic-based design
tool.
� Widely used in package; wave guide; and
antenna.
� UMC is the first foundry that provide the
methodology for using 3D EM design tool to
support RFIC design.
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EMDM Implement in Ansoft Tools
Virtuoso
AnsoftLink
ACIS
GDSII
DXF
Macros
UMC
Technology
File
Ansoft HFSS
Ansoft Designer
Inductance
Quality Factor
Self-Resonance
etc
13
Matrix Parameters
S-, Y-, Z-
Power Plug-in

AnsoftLink for Virtuoso
Easier than
“Cut & Paste”
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Ansoft Designer
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Number of Turns
– L & Q Comparison (1)
Quality Factor
10
8
6
4
2
0
-2
-4
0.18-micro 1P6M Inductor N=5.5 comparison
N5.5_s_Q
N5.5_m_Q
N5.5_s_L
N5.5_m_L
0 1 10 100
Frequency[GHz]
� Width= 10µm, Spacing= 2µm, Di= 85µm, Turns= 5.5, Al= 20KA
14
12
10
8
6
4
2
0
Inductance[nH]
16

Number of Turns
– L & Q Comparison (2)
Quality Factor
10
8
6
4
2
0
-2
-4
0.18-micro 1P6M Inductor N=4.5 comparison
N4.5_s_Q
N4.5_m_Q
N4.5_s_L
N4.5_m_L
0 1 10 100
Frequency[GHz]
� Width= 10µm, Spacing= 2µm, Di= 85µm, Turns= 4.5, Al= 20KA
14
12
10
8
6
4
2
0
Inductance[nH]
17

Inner Diameter – L Comparison
Inductance[nH]
10
9
8
7
6
5
4
3
2
1
0
-1
0.18-micro 1P6M Inductance/diff diameter
comparison
D150_s_L
D 85_s_L
D150_m_L
D 85_m_L
D230_s_L
D230_m_L
0 1 10 100
Frequency[GHz]
� Fixed width= 15µm, Spacing= 2µm, Turns= 2.5 & Al= 20KA,
Split Di: 85µm, 150µm and 230µm
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Increasing Metal Thickness (Al 30kA)
- L & Q Comparison
Quality Factor
12
10
8
6
4
2
0
-2
-4
-6
0.18-micro 1P6M Inductor Case2 comparison
Q_simulation
Q_measurement
L_simulation
L_measurement
0 1 10 100
Frequency[GHz]
� Width= 15µm, Spacing= 2µm, Di= 210µm, Turns= 5.5, Al= 30KA
30
27
24
21
18
15
12
9
6
3
Inductance[nH]
19

Pattern Ground Shielding – Deep Trench (1)
4.0um
� Using trench to reduce substrate loss.
20

Pattern Ground Shielding – Deep Trench (2)
Quality Factor
16
14
12
10
8
6
4
2
0
-2
-4
0.18-micro 1P6M Inductor with Deeptrench
comparison
DT_s_Q
DT_m_Q
DT_s_L
DT_m_L
0 1 10 100
Frequency[GHz]
� Width= 15µm, Spacing= 2µm, Di= 202µm, Turns= 5.5, Al= 30KA
� With 4.0um deep trench PGS
10
9
8
7
6
5
4
3
2
1
0
Inductance[nH]
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Other Applications by EDDM
� Interconnect RF model extraction
� Cross talk analysis in RF or high speed
digital IC
� Capacitor: MIM or MOM (fringing)
� Internal antenna design
� Package modeling for IC design
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Conclusions
� Customer’s success is always our first priority.
� UMC RF technology/design support is enhanced by
providing an accurate and efficient methodology for
inductor design.
� EMDM can be extended to other applications in
high frequency analysis.
� Reducing development cycle-time and cost,
customers can go into production much faster.
� UMC is always seeking better and improved
service for our customers.
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Contact persons in UMC:
H_C_Tseng@umc.com
Bigchoug_Hung@umc.com
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