Power Device Packaging
Z. Liang
Oak Ridge National Laboratory
May 10, 2010
Project ID: APE023This presentation does not contain any proprietary, confidential, or otherwise restricted information
2011 U.S. DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting
2 Managed by UT-Battellefor the U.S. Department of Energy
Overview
• Start Date: Oct. 2009• End Date: Sept. 2013• 40% Complete
• Existing automotive power module is one of the big obstacles to meet the VTP 2020 targets: Cost and Power Density
• State-of-the-Art power device/module packaging technologies have limitations in electrical, thermal, and reliability performance, as well as manufacturability
• Targets: – 60% power density increase and 40%cost
reduction, in line with DOE power electronics 2020 targets • DOE Share – 100%
• FY11 received: $650K• FY10 received: $480K
Timeline
Budget
Barriers
• ORNL Team Members: Puqi Ning, Andy Wereszczak, Randy Wiles, Laura Marlino
• The University of Tennessee: Fred Wang
Partners
3 Managed by UT-Battellefor the U.S. Department of Energy
ObjectiveThe fundamental efforts of this project is to Identify the limitations and shortcomings with existing device
packaging approaches;Develop new packaging concepts for improved electrical
performance, thermal management, reliability, and manufacturability; and
Complement other packaging and thermal management research efforts within the VTP Program.
FY11 • New power module packaging development: electrical and
thermal, thermo-mechanical performance evaluation and characterization, material/structure selection
• Sample modules fabrication, testing and analysis• Continue to benchmark State-of-the-art (SOA) technologies and
supply data to NREL for thermal/reliability modeling and simulation
• Provide packaging support for other APEEM projects
4 Managed by UT-Battellefor the U.S. Department of Energy
Milestone• Sept. 2010 - Selected/developed candidate technology
concepts.• Go No/Go Decision Point: Determined if selected
candidate packaging technologies could potentially meet the cost and density targets without compromising performance and reliability.
• Sept. 2011: Developed power modules offers improved performance in electrical, thermal and thermo-mechanical aspects; provided packaging support to other projects.
• Go/No Go – Whether the developed power modules have been identified that meet the target on cost and power density without compromising performance and reliability.
5 Managed by UT-Battellefor the U.S. Department of Energy
Approach• Develop in-house power electronics packaging capabilities
– Processing facilities for power electronics module packaging– Equipments and technologies for electrical, thermal and thermo-
mechanical characterization and analysis– Software and tools for power module design and analysis
• Benchmarking the state-of-the-art technologies– Comprehensively analyze the SOA automotive power modules– Micro-structural, mechanical and material characterization and
analysis of SOA module packaging technologies– Electrical, thermal and thermo-mechanical characterization of SOA
power modules• Develop new power electronics packaging technologies
– Electrical, mechanical structure optimization– High temperature, CTE matched material development– Processing innovation
• Provide prototype packaging and samples for other projects within the program
6 Managed by UT-Battellefor the U.S. Department of Energy
Integration of Power Electronics Packaging CapabilitiesChemical
Processing Station
Reflow Ovens
Thermal Cycle
Chamber
Wire Bonder
Encapsulate Set
Process Inspection Thermal
Shock Oven
Sintering Oven
Paste Printer
Clean Assembly
Bench
FY11 Technical Accomplishments (1)
7 Managed by UT-Battellefor the U.S. Department of Energy
Mod
ule
Toyota LS600 Toyota Prius III Infineon Hybridpack2 Mitsubishi TPM Semikron SKiM
Feat
ures
Adv
anta
ge
•Double sided planar interconnection;
•No baseplate;•Double sided cooling.
•Direct bond cooler;•No base plate;•No TiM layer;•Al Ribbon bond.
•Direct cooled base plate;
•No TiM layer;• Integrated cooler.
•No DBC substrate;
•Phase leg unit;•Direct planar
lead bond;
•No base plate;•Press contact;•Ag sintered die
attach.
Dis
adva
ntag
e
•Complex inverter (electrical and thermal) assembly;
•Ceramic slice insulation and double TiM layers.
•Stress relax buffer layer worsen thermal conductivity;
•Large electrical parasitic parameters.
•Difficulty in pin fin manufacture;
•Large electrical parasitic parameters;
•Difficult integration of cooler.
•Double TiMlayers;
•Poor thermal of TCIL;
•Module level assembly needed.
•Mechanical integrity concern;
•Large electrical parasitic parameters;
•Poor TiM layer uniformity.
General Evaluation of SOA Automotive Module PackagingFY11 Technical Accomplishments (2)
8 Managed by UT-Battellefor the U.S. Department of Energy
Microstructure & Mechanics Examination of SOA Packaging
Voids at Si/Ag interfaceSKiM
Solder Porosity
Al2O3
61Zr-15Al-1Cu-22O
Priu
s20
10TP
M
Hyb
ridPa
ck
FY11 Technical Accomplishments (3)
9 Managed by UT-Battellefor the U.S. Department of Energy
Automotive Power Module Design/Analysis Tool
0 100 200 300 400 500 600 70060
80
100
120
140
160
180
Time(S)
Tem
pera
ture
(C)
Temperature Profile Under US06 Drive Cycle
Ta=65CTa=105Cdie area S(cm2)=0.75die area S(cm2)=0.75
0 100 200 300 400 500 600 7000
50
100
150
200
250
300
Time(S)
Pow
er L
oss
(W)
An Inverter Power Loss Profile Under US06 Drive Cycle
EnergyLoss (J)=22599(S=0.75)
0 100 200 300 400 500 600 7000
50
100
150
200
250
300
Time(S)
Curr
ent(
A)
An Inverter Input Current Profile Under US06 Drive Cycle
0 5 10 15 20 25 30 35 40 45 50 55 60 65 700
5
10
15
20
25
30
35
40
45
50
55
60
65
70
Delta Tj(C)
Num
ber
An Inverter Delta Tj Profile Under US06 Drive Cycle
FY11 Technical Accomplishments (4)
10 Managed by UT-Battellefor the U.S. Department of Energy
Electrical Examination of SOA Module Packaging
0.80 mΩ18.3 nH12.9 nH
Positive
13 mΩ35.6 nH
Negative
Neutral
13 mΩ35.6 nH
0.87 mΩ
0.37 mΩ
0.37 mΩ
0.41 mΩ
0.41 mΩ10.6 nH 8.5 nH
10.6 nH 8.5 nH
0.80 mΩ18.3 nH12.9 nH0.87 mΩ
0.44 mΩ
11.3 nH14.4 nH
Positive
7 mΩ19.6 nH
Negative
Neutral
7 mΩ19.6 nH
0.33 mΩ
0.17 mΩ0.18 mΩ7.3 nH 6.5 nH
0.44 mΩ11.3 nH14.4 nH
0.33 mΩ
0.17 mΩ0.18 mΩ7.3 nH 6.5 nH
L=50.3nH R=2.35mΩ
L=39.5nH R=1.12mΩ
Prius 2010
Prius 2004
Packaging StructureElectromagnetic Simulation
FY11 Technical Accomplishments (5)
11 Managed by UT-Battellefor the U.S. Department of Energy
Time (S)
T j°C
Infineon HybridPack Module AssemblyWith 170 W power loss, Vgs= 6. 4 V, Im=3 mA
6080
100120
-0.0
08-0
.004 0
0.00
40.
008
0.01
20.
016
0.02
0.02
40.
028
Thermal Performance Examination of SOA Module Packaging
60
70
80
90
100
110
120
-8.00 2.00 12.00 22.00
9095
100105110
Toyota Prius 10 Module AssemblyWith 163 W power loss, Vgs= 6. 81 V, Im=3 mA
Time (S)
T j°C
θCooler
Pin
θjc
Tj
Tc
Ta(inlet)
0
100
200
300
400
500
600
0 25 50 75 100 125 150
Vce
(mV)
Tj (C)
FY11 Technical Accomplishments (6)
ToyotaPrius10 InfineonHP1ThermalResistance (C/W) 0.223 0.271Die area (10xcm2) 0.219 0.198SpecifcThermalResitance
(C.cm2/W) 0.489 0.536
0.000
0.100
0.200
0.300
0.400
0.500
0.600
Thermal PerformanceComparison
12 Managed by UT-Battellefor the U.S. Department of Energy
Develop New Packaging Concepts: Performance and Cost
Module Electrical Schematic
O
P
N
Gu
Eu
GL
EL
Novel Packaging Structure
Advanced Materials
Cost Effective Manufacture
Advanced Power Device Packaging Design
60% Thermal Performance Improvement of Infineon HP1
0.06 mΩ 0.06 mΩ3.6 nH 3.7 nHPositive
0.05 mΩ2.7 nH5 mΩ
13 nH
0.05 mΩ2.8 nH
2.7 nH
Negative
Neutral
5 mΩ13 nH
2.8 nH
3.6 nH 3.7 nH0.06 mΩ 0.06 mΩ
0.05 mΩ 0.05 mΩ
L=12.8nH
R=0.22mΩ
Electrical Parasitic Parameters (20-30% of Prius)200°C Reliable Operation Temperature; Material Selection
FY11 Technical Accomplishments (7)
13 Managed by UT-Battellefor the U.S. Department of Energy
Packaging Materials and Processes Development and Support Other Projects within the Program
WBG
IMMD
HT_IPM
FY11 Technical Accomplishments (8)
14 Managed by UT-Battellefor the U.S. Department of Energy
Collaboration and Coordination• NREL
– Collaborated within the Vehicle Technologies Program on thermal management/reliability
• ORNL Materials Science and Technology Division– Funded by DOE Materials Program– Coordinated their research activities to serve the materials need of
power electronics packaging
• University of Tennessee– Subcontractor, to help benchmark commercial packages
• Virginia Tech University– Collaborated on die attach material and power electronics module
packaging
15 Managed by UT-Battellefor the U.S. Department of Energy
Future Work – FY11• Complete fabrication of the new concept power
modules in-house– Complete the fixtures design and process parameters
selection
– Complete the process integration for designed all planar bonding structure
– Conduct preliminary performance tests• Continue to evaluate and down select packaging
technologies (materials and processes)• Continue to support new power electronics module
development
16 Managed by UT-Battellefor the U.S. Department of Energy
Future Work – FY12 and Beyond• Power module packaging structure optimization
– Electrical and thermo-mechanical performance evaluation and characterization, based on the experimental data
• Inverter-level packaging study and new concept development – Integration of power modules into high density
inverter/converter
• Testing and analysis– Electrical, thermal, and thermal-mechanical properties
• Continue to benchmark SOA technologies• Continue materials evaluation and process
development for high temperature power module• Provide packaging support for other projects
17 Managed by UT-Battellefor the U.S. Department of Energy
Summary• The in-house power electronics packaging capability
has been enhanced, which enables greatly advanced packaging technology development.
• The state-of-the-art automotive power modules and their packaging technologies have been benchmarked by various methods, electrically, thermally and mechanically.
• An advanced automotive power module has been designed. The associated packaging materials and processes development have been performed.
• The power electronics packaging support has been provided for several projects in the portfolio.