The market size of TIMs for EV power electronics will exceed US$600 million by 2034.

Thermal Management for EV Power Electronics 2024-2034: Forecasts, Technologies, Markets, and Trends

Granular ten-year TIM, die-attach and substrate-attach market forecasts for Si IGBT, SiC MOSFETs, and GaN. Liquid Cooling forecast for inverters and motors. Power module suppliers' profile and supply chain analysis.

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IDTechEx has observed a growing trend towards 800V platforms and beyond, driven by several automotive OEMs including GM, Hyundai, VW, and Lucid Motors. These platforms, operating at higher voltages, are enhancing efficiency by minimizing joule losses and enabling the downsizing of high-voltage cabling, thereby reducing weight. This transition is facilitated by the adoption of new technologies and materials, particularly silicon carbide (SiC) MOSFETs, which incorporate innovative thermal management techniques and materials such as double-sided cooling (DSC), advanced Ag sintered die-attach, alongside the use of high-performance thermal interface materials.
Moving from traditional silicon IGBTs to SiC MOSFETs also entails changes in thermal architecture design. Examples include the implementation of DSC, copper ribbon bonding, and direct liquid cooling to eliminate the need for thermal interface materials (TIMs).
In its report titled "Thermal Management for EV Power Electronics 2024-2034: Forecasts, Technologies, Markets, and Trends", IDTechEx offers a comprehensive market forecast for power electronics thermal management strategies, segmented by SiC MOSFET, Si IGBT, and GaN technologies. The report provides detailed projections for die-attach, substrate-attach, and TIM area, volume, and market value by SiC, Si, and GaN, as well as a breakdown of die-attach methods including traditional solders, Ag sintering, and emerging Cu sintering. Additionally, the report covers the market for liquid-cooled inverters, segmented by air, oil, and water-glycol cooling methods.
Power Electronics Thermal Material Evolution
As power semiconductors experience increased power density and heat flux, coupled with the transition from Si IGBT to SiC MOSFET, the thermal architecture of power semiconductor packaging is anticipated to undergo significant changes. The diagram provided illustrates the key layers of materials in power modules, comprising die-attach materials, substrate-attach materials, wire bonding, and thermal interface materials.
The semiconductor dies are affixed to a double-bonded ceramic (DBC) substrate using die-attach materials. Subsequently, the DBC is connected to a baseplate via another substrate-attach material. Communication between the dies and circuitry is facilitated through wire bonding, traditionally using aluminum but with a growing preference for copper. To ensure protection and stability, the package is potted with thermally conductive silicone gels.
Die-attach and substrate-attach materials
Die-attach and substrate-attach materials typically consist of solder alloys like SnPb or SAC (Sn-Ag-Cu). These alloys are chosen for their high bulk thermal conductivity, and upon soldering, they form intermetallics between components, resulting in low interfacial thermal resistance. This maintains low package stress and processing temperature while also mechanically fastening the heat sink. The typical thermal conductivity of solder alloys is around 50W/mK, with melting temperatures around 200°C.
However, as heat flux increases due to the transition from Si IGBT to SiC MOSFET, junction temperatures are expected to surpass 175°C, or even 200°C in some cases, posing challenges for traditional solders. This shift has led to a transition from solders to sintered die-attach materials. Some leading automotive OEMs, including Tesla, Hyundai, and BYD, have already begun adopting Ag-sintered die-attach materials. Nonetheless, Ag-sintered pastes are significantly more expensive than traditional solder alloys. While costs are influenced by customer relationships, order volume, and various other factors, IDTechEx estimates that Ag-sintered pastes can be 5 times more expensive than traditional solder alloys. In the short to medium term, it is expected that silver sintered paste will primarily be adopted by leading automotive OEMs due to their greater bargaining power with higher volumes to reduce costs. There is also scope for people to replace Cu-sintered die-attach thanks to their theoretically lower costs compared with Ag-sintered die-attach. However, as of 2024, IDTechEx has not seen any large-scale commercial examples of Cu-sintered die-attach materials. This report compares and analyzes the benefits and drawbacks of Ag and Cu-sintered die-attach, along with the market forecast of these two technologies. Despite the benefits of sintering, many semiconductor suppliers and automotive OEMs will remain with solder alloys due to their reduced cost and advances happening with their application.
TIM2 typically comes in two forms in EV power semiconductors: thermal grease, employed between the baseplate and the heatsink, and thermal gel, often utilized as potting materials. The market in 2024 sees thermal greases typically exhibiting a thermal conductivity between 2.5 and 3.5W/mK and a density of around 2.5g/ml. However, there have been advancements in TIMs, such as Honeywell's PTM7000 used in onsemi's VE-Trac, demonstrating a thermal conductivity of 6.5W/mK. IDTechEx predicts a trend towards higher thermal conductivity due to the increasing heat flux resulting from the adoption of SiC technology. Further to this, phase change materials (PCM) also gain significant momentum thanks to their superior latent heat capacity. The thermal impedance using PCM can reduce by over 50% compared with traditional thermal grease, although this largely depends on the materials used, configurations, and many other factors. The report benchmarks a number of commercial TIM2 options and conducts a granular analysis of their mechanical properties.
Power Electronics Cooling Strategy
The Thermal Management for EV Power Electronics report also summarizes the emerging trends in thermal architecture evolution. Take the two trends below as an example.
1. Double-sided cooling (DSC): Double-sided cooling has been implemented in some mid- to high-end electric vehicles, such as the Porsche Taycan and Audi e-tron. This approach offers superior cooling capacity where the junction temperature can be reduced by 40%. However, the adoption of double-sided cooling results in a more complicated and expensive design. In contrast to single-sided cooling, DSC replaces wire bonding with lead frames and may potentially double the amount of die attach and TIM used.
2. Direct liquid cooling: Another emerging trend is the transition from traditional cooling methods to direct liquid cooling, where the double-bonded copper (DBC) is directly affixed to a pin-fin structured heatsink. This configuration allows for the elimination of the cold plate and thermal grease.
Market Opportunities
The report forecasts that the combined market size of die-attach materials, substrate-attach materials, and TIM2 for EV power electronics will reach approximately US$900 million by 2034, presenting significant market opportunities. As thermal power continues to rise, it is expected that more advanced thermal management strategies will be adopted, thereby accelerating market growth at a double-digit Compound Annual Growth Rate (CAGR) from 2024 to 2034.
For a deeper understanding of the market opportunities, active players, competitive landscape, technology benchmarking, and recent market developments, readers are encouraged to refer to IDTechEx's latest report, "Thermal Management for EV Power Electronics 2024-2034: Forecasts, Technologies, Markets, and Trends".
Key aspects
This report provides critical market intelligence about the area, volume, weight, and market value of die-attached solders, substrates, and TIM2s for electric vehicle power electronics, in particular, Si IGBT, SiC MOSFET, and GaN.
  • A review of the power electronics, including Si IGBT, SiC MOSFET, and GaN.
  • An analysis of the TIMs for different layers in EV power electronics, including die attach, substrate attach and TIM2.
  • A summary of SiC MOSFET suppliers by automotive OEMs and semiconductor suppliers.
  • An in-depth technology analysis and commercial use case analysis of single and double-sided cooling.
  • An in-depth technology analysis of TIM1s (die attach and substrate attach), including solders, silver sintered TIMs, and copper sintered TIMs. An overview of Cu sintering paste suppliers.
  • Technology analysis of TIM2 in Si IGBT and SiC MOSFET. A benchmark comparison of thermal conductivity, thickness, and specific gravity.
  • Wire bonding technologies and trends.
  • Review of substrate materials and market share of EV power semiconductor/module suppliers.
  • A comprehensive analysis of power electronics supply chain, including semiconductor suppliers, power module suppliers to inverter makers and automotive OEMs.
  • Review of water and oil cooling of power modules.
  • Comparison of TIM area per kW of power (mm2/kW) for die attach, substrate attach and TIM2.
  • Die attach material area and market value forecast from 2024 to 2034.
  • Substrate attach material area and market value forecast from 2024 to 2034.
  • TIM2 area and market value forecast from 2024 to 2034.
  • Motor and inverter cooling by air, oil, and water-glyco.
Report MetricsDetails
Historic Data2021 - 2023
CAGRThe global TIM market for power electronics in battery electric vehicles and plug-in hybrid electric vehicles will exceed US$900 millions by 2034.
Forecast Period2024 - 2034
Forecast UnitsUS$, kg, m2, m3
Regions CoveredWorldwide
Segments CoveredSiC MOSFET, Si IGBT, GaN, Die Attach, Substrate Attach, Thermal Interface Material 2, Inverters, Onboard Chargers, DC-DC Converters, Liquid Cooling (air, oil, and water-glyco) for Motors and Inverters, Power Module Suppliers, Single and Double-Sided Cooling, Power Module and Discrete Market Share.
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Table of Contents
1.1.General Trend of TIMs in Power Electronics (1)
1.2.General Trend of TIMs in Power Electronics (2)
1.3.Where are TIMs used in EV Power Electronics
1.4.SiC MOSFET by Automotive OEMs and Suppliers
1.5.Trend Towards Double-Sided Cooling for Automotive Applications
1.6.Transition to Double-Sided Liquid Cooling
1.7.Market Share of Single and Double-Sided Cooling: 2024-2034
1.8.Summary of TIM2 Properties
1.9.BLT Comparison of TIM2
1.10.Coefficient of Thermal Expansion (CTE) Comparison of Die-Attach and Substrate-Attach
1.11.Thermal Conductivity Comparison of TIM1s
1.12.Yearly Die Attach Area Forecast (1000m2): 2024-2034
1.13.Yearly Die Attach Area Forecast by Type (1000m2): 2024-2034
1.14.Yearly Substrate Attach Area Forecast (1000m2): 2024-2034
1.15.Yearly TIM2 Area Forecast (1000m2): 2024-2034
1.16.Yearly Market Size of TIMs Forecast (US$ Millions): 2024-2034
1.17.Inverter Liquid Cooling Strategy Forecast (Unit: Millions): 2024-2034
2.1.An Overview of Power Electronics TIMs
2.2.Summary of Cooling Approaches - (1)
2.3.Summary of Cooling Approaches - (2)
2.4.Thermal Management Strategies in Power Electronics (1)
2.5.Thermal Management Strategies in Power Electronics (2)
2.6.What is Power Electronics?
2.7.Power Electronics Use in Electric Vehicles
2.8.Power Electronics Material Evolution
2.9.Transistor History & MOSFET Overview - How Does it Affect Thermal Management?
2.10.Wide Bandgap (WBG) Semiconductor Advantages & Disadvantages
2.11.Benchmarking Silicon, Silicon Carbide & Gallium Nitride Semiconductors
2.12.Advantages of SiC Material
2.13.The Transition to SiC (market share 2015-2023)
2.14.Is all 800V SiC? Audi e-tron 2018 and Porsche Taycan?
2.15.Limitations of SiC Power Devices
2.16.GaN's Potential to Reach High Voltage
2.17.SiC & GaN have Substantial Room for Improvement
2.18.Automotive GaN Device Suppliers are Growing
2.19.SiC Drives 800V Platforms
2.20.GaN to Become Preferred OBC Technology
2.21.Challenges for GaN Devices
2.22.Inverter Overview
2.23.Traditional EV Inverter Power Modules
2.24.Inverter Package Designs
2.25.Power Module Packaging
2.26.Module Packaging Material Dimensions
2.27.Trends Toward Minimization
2.28.Single Side, Dual Side, Indirect, and Direct Cooling
2.29.Baseplate, Heatsink, and Encapsulation Materials
2.30.Cooling Concept Assessment
3.1.Key Summary of Single-Sided Cooling
3.2.Benefits and Drawbacks of Single-Sided Cooling
3.3.TIM2 Area Largely Similar for Single-Sided Cooling
3.4.onsemi - EliteSiC Power Module
3.5.ST Microelectronics - Tesla Model 3
4.1.Key Summary of Double-Sided Cooling (DSC)
4.2.Double-Sided Cooling Introduction
4.3.Double-Sided Cooling Examples
4.4.The Need for Double-Sided Cooling in Power Modules
4.5.Infineon's HybridPACK DSC
4.6.Inner Structure of HybridPACK DSC
4.7.onsemi - VE-Trac Family modules
4.9.Hitachi Inverter - Double-Sided Cooling
4.10.Trend Towards Double-Sided Cooling for Automotive Applications
4.11.Market Share of Single and Double-Sided Cooling: 2024-2034
5.1.1.Introduction to TIM1
5.1.2.TIM1 in Flip Chip Packaging
5.1.3.Trends of TIM1 in 3D Semiconductor Packaging
5.1.4.Solder TIM1 and Liquid Metal
5.1.5.Solders as TIM1
5.1.6.Solder TIM1 - Minimize Warpage and Delamination (1)
5.1.7.Solder TIM1 - Minimize Warpage and Delamination (2)
5.1.8.Device Packaging Dynamics
5.1.9.MacDermid Alpha - Solders for Automotive Power Electronics
5.1.10.Trend Towards Sintering
5.1.11.Market News and Trends of Sintering
5.2.Ag Sintered TIM
5.2.1.Metal Sheet, Graphite Sheet, and Ag Sintered TIM
5.2.2.Process Steps for Applying Ag Sintered Paste
5.2.3.Die-Attach Solution - Summary of Materials (1)
5.2.4.Die-Attach Solution - Summary of Materials (2)
5.2.5.Silver Sintering Paste
5.2.6.Properties and Performance of Solder Alloys and Conductive Adhesives
5.2.7.Solder Options and Current Die Attach
5.2.8.Why Sliver Sintering
5.2.9.Silver-Sintered Paste Performance
5.2.10.Sumitomo Bakelite
5.2.11.Henkel - Die Attach Paste
5.2.12.Osaka Soda - Ag Sintered Paste
5.2.13.MacDermid Alpha
5.2.15.Company Profiles for Sintered Paste Suppliers
5.3.Cu Sintered TIM
5.3.1.Cu Sinter Materials
5.3.2.Cu Sintering: Characteristics
5.3.3.Reliability of Cu Sintered Joints
5.3.4.Graphene Enhanced Sintered Copper TIMs
5.3.5.Mitsubishi Materials: Cu Sinter Material Poised for Market Entry
5.3.6.Mitsubishi Materials: Copper Alloys to Improve Power Density
5.3.7.Mitsui: Cu Sinter Half the Cost of Ag Sinter
5.3.8.Copper Sintering - Challenges
5.3.9.Porosity (%) of Metal Sinter Paste
5.3.10.Hitachi: Cu Sintering Paste
5.3.11.Indium Corporation: Nano Copper Paste
5.3.12.Mitsui Mining. - Copper Sinter Paste Pressure and Pressureless
5.3.13.Mitsui Mining: Nano Copper Under N2
5.3.14.Showa Denko, formerly Hitachi Chemical - Cu sinter [P]
5.3.15.Showa Denko, formerly Hitachi Chemical - Cu sinter [N] and Cu sinter [F]
5.3.16.Mitsui: Cu Sinter - Half the Cost of Ag Sinter
5.3.17.Summary of Cu sinter [P], Cu sinter [N], and Cu sinter [F]
6.1.1.Thermal Interface Material 2 - Summary
6.1.2.TIM2 - IDTechEx's Analysis on Promising TIM2
6.2.TIM2 in Si IGBT
6.2.1.Why TIM2 is Used in Power Electronics
6.2.2.Where are TIM2 Used in EV IGBTs?
6.3.TIM2 EV Power Module Use Cases
6.3.1.TIMs in Infineon's IGBT
6.3.2.TIMs in onsemi IGBT Modules
6.3.3.Semikron Danfoss - TIM Overview
6.3.4.Semikron Danfoss - Graphite TIM
6.3.5.TIMs in Mitsubishi Electric - IGBT modules NX type
6.3.6.Nissan Leaf 2012 Inverter
6.4.High-Performance TIM2s
6.4.1.Arieca - Liquid Metal Based Polymer TIM for the Semiconductor Industry
6.4.2.Zeon - High Performance TIMs
6.4.3.Thermexit (Nanoramic Labs): High Thermal Conductivity Materials
6.4.4.TIMs from Wacker Chemical Group
6.5.TIM2 in SiC MOSFET
6.5.1.SiC MOSFETs Compared with Si IGBTs
6.5.2.TIMs in onsemi SiC MOSFET
6.5.3.Pre-Apped TIM in Infineon's CoolSiC
6.5.4.Infineon's SiC MOSFET Thermal Resistance
6.5.6.TIMs in Wolfspeed's SiC Power Modules
6.5.7.Microchip - SiC MOSFETs
6.5.9.Solders as TIM2s - Package-Attach from Indium Corp
6.6.Removing Thermal Interface Material
6.6.1.Why the Drive to Eliminate the TIM?
6.6.2.Thermal Grease: Other Shortcomings
6.6.3.EV Inverter Modules Where TIM has Been Eliminated (1)
6.6.4.EV Inverter Modules Where TIM has Been Eliminated (2)
6.6.5.Hitachi DSC package used in Audi e-Tron
7.1.Overview of TIM2 in SiC MOSFET and Si IGBT - (1)
7.2.Overview of TIM2 in SiC MOSFET and Si IGBT - (2)
7.3.Overview of TIM2 in SiC MOSFET and Si IGBT - (3)
7.4.Overview of TIM1 in SiC MOSFET and Si IGBT (1)
7.5.Overview of TIM1 in SiC MOSFET and Si IGBT (2)
7.6.IGBTs and SiC are not the Only TIM Area in Inverters
7.7.Summary of TIM2 Properties
7.8.Choice of Non-Bonded TIMs
7.9.BLT Comparison of TIM2
7.10.Coefficient of Thermal Expansion (CTE) Comparison of TIM1
7.11.Thermal Conductivity Comparison of TIM1s
7.12.Temperature Considerations of TIM1s
7.13.TIM1 - Size of the Die
7.14.Summary of Die Attach Sizes: 2024-2034
8.1.Wire Bonds
8.2.Al Wire Bonds: A Common Failure Point
8.3.Advanced Wire Bonding Techniques
8.4.Tesla's Novel Bonding Technique
8.5.Direct Lead Bonding (Mitsubshi)
8.6.Die Top System - Heraeus
8.7.Danfoss Bond Buffer - IGBT
8.8.Wire Bond Technology by Supplier
8.9.Wire Bond Trend: Copper Wire and Direct Lead Bonding
9.1.The Choice of Ceramic Substrate Technology
9.2.The Choice of Ceramic Substrate Technology
9.3.Materials of Substrate - Comparison
9.4.Comparison of Al2O3, ZTA, and Si3N4 Substrate
9.5.Materials in Packaging
9.6.Substrate - Key for Market Penetration?
9.7.Substrate Area Estimation (mm2/kW)
9.8.Substrate Manufacturing - SOITEC's SiC Substrates (1)
9.9.SOITEC's SiC Substrates (2)
9.10.Approaches to Metallization: DPC, DBC, AMB and Thick Film Metallization
9.11.Double Bonded Copper (DBC): Pros and Cons
9.12.Active Metal Brazing (AMB): Pros and Cons
9.13.Si3N4 Substrate: Overall Best Performance with Low Cost-Effectiveness
9.14.Si3N4 Ag Free AMB Market Position
9.15.AlN: Overcoming its Mechanical Weakness
10.1.Automotive Power Module Supplier Market Shares
10.2.Evolving SiC Supply Relationships
10.3.SiC Supply Chain in 2023
10.4.Power Electronics Supply Chain - Trend Towards SiC
10.5.Summary of Power Electronics Supplier
10.6.Summary of Automotive OEMs, Tier Ones and Power Electronics Suppliers (1)
10.7.Summary of Automotive OEMs, Tier Ones and Power Electronics Suppliers (2)
10.8.SiC MOSFET by Automotive OEMs and Suppliers - Leading OEMs
11.1.Direct and Indirect Cooling (1)
11.2.Direct and Indirect Cooling (2)
11.3.Inverter Package Cooling
11.4.Drivers for Direct Oil Cooling of Inverters
11.5.Advantages, Disadvantages and Drivers for Oil Cooled Inverters
11.6.Direct Oil Cooling Projects
11.7.Fraunhofer and Marelli - Directly Cooled Inverter
11.8.Hitachi - Oil Cooled Inverter
11.9.Jaguar I-PACE 2019
11.10.Lucid - Water Cooled Onboard Charger
11.11.Nissan Leaf
11.12.Renault Zoe 2013 (Continental)
11.14.Senior Flexonics - IGBT Heat Sink Design
11.15.Tesla Model 3
11.16.VW ID
11.17.BorgWarner Heat Sinks
11.18.Emerging 800V Platforms & SiC Inverters
11.19.Inverter Liquid Cooling Strategy Forecast (Unit: Millions): 2024-2034
12.1.Use Case: Direct Water Cooling - Hitachi Suijin Series
12.2.Use Case: GaN Systems HybridPack
12.3.Use Case: Infineon - HybridPACK™ Drive
12.4.Use Case: Mitsubishi J1-Series
12.5.Use Case: Semikron Skim 93
12.6.Use Case: Wolfspeed - Cree FM3, Cree XM 3
12.7.Use Case: Denso Power Card
12.8.TIM2 - Area Estimation of STMicroelectronics ACEPACK SMIT
12.10.Bosch's SiC Inverter Progress
12.11.Infineon and STMicro Inverter Package Materials
12.12.New Power Modules from Mitsubishi
12.13.Chinese Automotive OEMs - Vertical Integration and Local Suppliers
13.1.Area and Volume Estimation of Different Layers in IGBT Components
13.2.Area Estimation of TIM2
13.3.Summary of Power Electronics Supplier in EV Industry
13.4.Area of SiC MOSFET, Si IGBT and GaN HEMT
13.5.Shrinking Die Sizes with SiC MOSFETs
13.6.Trend of Die Sizes - Si IGBT and SiC MOSFET
13.7.SiC MOSFET and Si IGBT: Die Area for Inverters - mm2/kW
13.8.Table Summarizing the Si IGBT and Si MOSFET Die Area for Inverters
13.9.SiC MOSFET and Si IGBT - mm2/kW Comparison for Inverters
13.10.Yearly TIM Area Forecast for EV Power Electronics (1000m2): 2024-2034
13.11.Yearly TIM Area Forecast by TIM Type
13.12.Yearly Die Attach Area Forecast for BEV & PHEV (1000m2): 2024-2034
13.13.Die Attach Area by Technology Forecast - m2: 2024-2034
13.14.Yearly Die Attach Area by Vehicle Component Forecast - m2: 2024-2034
13.15.Yearly Die Attach Area Forecast by Solder Type (m2): 2024-2034
13.16.Market Share of Discrete and Modules: 2024-2034
13.17.TIM2 Area Estimation for Inverters
13.18.Yearly TIM2 Area Forecast (m2): 2024-2034
13.19.Yearly Substrate Attach Area Forecast by Tech (m2): 2024-2034
13.20.Cost Forecast - TIM2, Solder Alloy Die-Attach, Solder Alloy Substrate-Attach and Ag-Sintered Paste: 2024-2034
13.21.Yearly Market Size Forecast of TIM1 and TIM2 (US$ Millions): 2024-2034
13.22.Inverter Liquid Cooling Strategy Forecast (Unit: Millions): 2024-2034

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Slides 257
Forecasts to 2034
Published Mar 2024
ISBN 9781835700297

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