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 interfaceSK

iM

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.

Power Device Packaging�OverviewObjectiveMilestoneApproachFY11 Technical Accomplishments (1)FY11 Technical Accomplishments (2)FY11 Technical Accomplishments (3)Slide Number 9Slide Number 10FY11 Technical Accomplishments (6)FY11 Technical Accomplishments (7)FY11 Technical Accomplishments (8)Collaboration and CoordinationFuture Work – FY11Future Work – FY12 and BeyondSummary