Modern Power Electronic Devices: Physics, Applications, and Reliability

Cover
Contents
About the editor
Preface
1 Introduction: Power Electronics challenges
1.1 Power Electronics
1.2 Power devices: the core of Power Electronics
1.3 Wide-bandgap semiconductors
1.4 Operational range
1.5 Temperature, reliability and other challenges
1.6 Summary
Note to the reader
References
2 Junction diodes
2.1 Introduction
2.2 PN junction
2.2.1 Definition and types
2.2.2 Equilibrium PN junction
2.2.3 Nonequilibrium PN junction
2.2.4 PN junction breakdown
2.2.5 PN junction capacitance
2.3 PiN diodes
2.3.1 Structures and operation principle
2.3.2 Characteristics and parameters
2.3.3 Typical application [4]
2.3.4 Instabilities
2.3.5 SiC PiN diodes [7–34]
2.4 FRDs (fast recovery diodes)
2.4.1 Structures and operation principle
2.4.2 Characteristics and parameters
2.4.3 Typical application [42]
2.4.4 Instabilities
2.5 DSRDs (drift step recovery diodes)
2.5.1 Structures and operation principle
2.5.2 Characteristics and parameters
2.5.3 Typical application
2.5.4 SiC DSRDs
2.6 Summary
Note to the reader
References
3 Thyristors
3.1 Introduction
3.2 History and current state
3.3 The thyristor structure and its two-transistor analogue
3.4 Forward and reverse blocking
3.4.1 Advanced methods for optimisation of blocking capability
3.4.2 Junction termination
3.5 Turn-on into the ON-state
3.5.1 Turn on by the gate current IG
3.5.2 Turn on by the light pulse
3.5.3 Turn on by overcoming the break-over voltage VBO
3.5.4 Turn on by a fast rise of the anode voltage (by overcoming the VBO at high dV/dt)
3.6 Turn off
3.7 Serial and parallel connections
3.7.1 Serial connection of thyristors
3.7.2 Parallel connection of thyristors
3.8 Summary
Note to the reader
References
Further reading
4 Silicon MOSFETs
4.1 Introduction
4.2 High-voltage MOSFETs
4.2.1 The silicon limit
4.2.2 The Superjunction principle
4.2.3 Electric characteristics of Superjunction devices
4.3 Lowand medium-voltage MOSFETs
4.3.1 The vertical trench MOSFET versus the shielded-gate MOSFET
4.3.2 Electric characteristic
4.4 Summary
Note to the reader
References
5 Silicon IGBTs
5.1 Introduction
5.2 The IGBT structure, equivalent circuit and operation
5.3 The IGBT static characteristics
5.4 The IGBT switching characteristics
5.4.1 Turn-on transient
5.4.2 Turn-off transient
5.5 The IGBT main requirements and structural evolution
5.5.1 Losses reductions due to bulk optimisation
5.5.2 Losses reductions due to MOS cell optimisation
5.6 Short circuit and related instabilities in IGBTs
5.6.1 Short-circuit turn-on transient
5.6.2 Short-circuit turn-off transient
5.6.3 Short circuit failure modes in IGBTs
5.6.4 Analysis of IGBT short circuit failure modes I and II
5.6.4.1 Effect of the voltage supply
5.6.4.2 Effect of gate voltage supply
5.6.4.3 Effect of temperature
5.6.5 Short circuit oscillation phenomenon
5.7 Safe operating area of IGBTs
5.7.1 Dynamic avalanche and IGBT failure mode during turn-off
5.7.2 IGBT turn-off under SOA conditions
5.7.3 Switching self-clamp mode failure during turn-off
5.8 IGBT development trends
5.8.1 Increase in absolute power
5.8.1.1 Area increase
5.8.1.2 Integration solutions
5.8.1.3 Reverse conducting RC-IGBT
5.8.2 Increase in power density
5.8.2.1 Losses reductions
5.8.2.2 Higher operating temperature
5.8.2.3 Safe-operating-area and short circuit margins
5.9 Summary
Note to the reader
References
6 IGCTs
6.1 Introduction
6.2 History
6.3 Device types
6.4 Gate turn-off thyristors (GTOs)
6.5 IGCT operation
6.6 Silicon design
6.7 Similar devices
6.8 Turn-on
6.9 Turn-off
6.9.1 Stray inductance
6.9.2 Device design
6.9.3 Temperature
6.10 Data-sheet parameters
6.10.1 Ratings
6.10.1.1 IFAV, ITAV – Maximum allowable average forward current
6.10.1.2 IFRMS, ITRMS – Maximum root mean square current
6.10.1.3 Tvj – Virtual junction temperature
6.10.1.4 VDRM – Maximum direct repetitive voltage
6.10.1.5 VRRM – Maximum reverse repetitive voltage
6.10.1.6 VLTDS or VDC – Long-term DC stability or permanent voltage
6.10.1.7 VRPM – Maximum reverse permanent voltage
6.10.1.8 VDSM – Maximum direct surge voltage
6.10.1.9 VRSM – Maximum reverse surge voltage
6.10.1.10 VDWM – Maximum direct working voltage
6.10.1.11 VRWM – Maximum reverse working voltage
6.10.1.12 ITSM, IFSM – Maximum forward surge current
6.10.1.14 di/dt – Maximum rate-of-rise of on-state current
6.10.1.16 PGAV – Average gate power
6.10.1.17 PGM, IFGM, VFGM – Maximum gate power, current, voltage
6.10.1.18 VRGM – Maximum reverse gate voltage
6.10.2 Characteristics
6.10.2.1 VFM, VTM – Maximum on-state voltage
6.10.2.2 IDRM – Maximum direct repetitive leakage current
6.10.2.3 IRRM – Maximum reverse repetitive leakage current
6.10.2.4 IDPM, IRPM – Maximum direct/reverse permanentleakage current
6.10.2.4 IDPM, IRPM – Maximum direct/reverse permanent leakage current
6.10.2.6 IGT – Gate current to trigger
6.10.2.7 IGM – Maximum initial gate current
6.10.2.8 EON – Turn-on energy
6.10.2.9 EOFF – Turn-off energy
6.10.2.10 PT – Power loss
6.10.2.11 RTH(C-S) – Thermal resistance case-to-sink
6.10.2.12 RTH(J-C) – Thermal resistance junction-to-case
6.10.2.13 TC – Case temperature
6.10.2.14 tgt – Maximum turn-on time
6.10.2.15 TON-MIN
6.10.2.16 TOFF-MIN
6.11 Gate drive
6.12 The clamp circuit
6.13 IGCT applications
6.13.1 IGCT VSIs and CSIs
6.13.1.1 VSIs
6.13.1.2 CSIs
6.13.2 Series connection
6.13.3 Parallel connection
6.14 Mechanical mounting
6.15 Circuit simulation
6.16 Present and future
6.17 Reliability
6.18 Summary
Note to the reader
References
7 Silicon carbide diodes
7.1 Introduction
7.2 Review of silicon carbide SBD structures
7.3 Edge termination and reverse bias reliability
7.4 Measurement of application relevant parameters
7.5 Operation in applications
7.6 Future developments
7.7 Summary
Note to the reader
References
8 SiC MOSFETs
8.1 Introduction
8.2 Principle of operation
8.2.1 Planar MOSFET
8.2.2 Trench-gate MOSFET
8.2.3 Super junction MOSFET
8.3 SiC/SiO2 interface challenge
8.4 A comparison between Si MOSFET and SiC MOSFET
8.5 Short-circuit capability
8.5.1 Short-circuit test
8.5.2 Short-circuit failure mechanisms in SiC MOSFETs
8.5.2.1 High voltage, short pulse tests
8.5.2.2 Low voltage, long pulse tests
8.5.3 Short-circuit aging effect
8.5.4 Short-circuit gate leakage current
8.6 Avalanche capability
8.7 Summary
Note to the reader
References
9 GaN metal-insulator-semiconductor field-effect transistors
9.1 Introduction: recent progress in GaN power devices and applications
9.2 Principle of operation
9.2.1 GaN-on-Si power transistor structures
9.2.2 Normally-off GaN device technologies
9.2.2.1 Two-chip hybrid cascode configuration
9.2.2.2 Single-chip E-mode GaN transistors
9.2.3 Challenges in GaN power transistors
9.2.3.1 Gate instability and reliability
9.2.3.2 Dynamic ON-resistance (
9.3 Gate instability and reliability
9.3.1 Mechanisms of gate instability
9.3.1.1 VTH shift in MIS-gate GaN transistors
9.3.1.2 VTH shift in p-GaN gate GaN transistors
9.3.2 Characterization techniques
9.3.2.1 Mapping of interface/border trap distribution
9.3.2.2 Evaluation of VTH instability under static/dynamicstress
9.3.3 Time-dependent dielectric breakdown
9.4 Dynamic performance
9.4.1 Dynamic ON-resistance (RON)
9.4.1 Dynamic ON-resistance (RON)
9.4.1.1 VTH-instability-induced dynamic RON: role of gate overdrive
9.4.1.2 Buffer-induced dynamic
9.4.2 Characterization techniques
9.4.2.1 Wafer-level tests
9.4.2.2 Board-level tests
9.4.3 Prospects and solutions
9.4.3.1 Dynamic RON suppression in lateral GaN-on-Si devices
9.4.3.2 Superior dynamic RON performance in vertical GaN-on-GaN devices
9.5 Summary
Note to the reader
References
10 Gallium nitride transistors: applications and vertical solutions
10.1 Introduction
10.2 Advantages of GaN for power devices
10.2.1 Material device and system-level benefit of GaN
10.3 GaN applications and market trends
10.3.1 Applications and market value
10.4 GaN power HEMT
10.4.1 GaN heterostructure-based transistors
10.5 Vertical GaN transistors
10.5.1 Fabricated solutions for vertical and quasi-vertical GaN FETs
10.5.1.1 CAVET
10.5.1.2 Trench MOSFET
10.5.1.3 Slanted HEMT PGaN gate
10.5.1.4 FinFET
10.5.1.5 Quasi-vertical GaN-on-Si
10.5.1.6 Super junction vertical GaN devices
10.6 Summary
Note to the reader
References
11 Module design and reliability
11.1 Introduction
11.2 Multi-physics design for power module
11.2.1 EM simulation of power module
11.2.1.1 Low inductance design
11.2.1.2 Low-frequency EM simulation
11.2.1.3 Substrate layout optimisation based on EM simulation
11.2.1.4 EM Lorentz force analysis for short-circuit failure
11.2.2 EM-circuitry design in module packaging
11.2.3 Thermal design and thermal analysis
11.2.4 Thermal-mechanical design
11.3 Enhancement of power module reliability
11.3.1 Bonding materials and processes
11.3.1.1 Wire bonding
11.3.1.2 Soldering
11.3.1.3 Silver sintering
11.3.1.4 Ultrasonic welding
11.3.2 High insulation material and processes
11.3.2.1 Ceramic substrate
11.3.2.2 Baseplate
11.3.2.3 Encapsulant and process
11.3.3 Electrical and reliability test
11.3.4 Environment test
11.4 Summary
Acknowledgements
Note to the reader
References
12 Switching cell design
12.1 Introduction
12.2 The concept for integrated switching cell
12.3 Thermal interface
12.4 Electrical interfaces
12.4.1 Insulation: clearance/creepage distances
12.5 Mechanical interfaces
12.6 DC link design
12.6.1 State-of-the-art DC link design
12.6.2 DC link design for fast switching power modules
12.6.3 Design rules for capacitor
12.6.4 Damping resistor Rsnubb design
12.7 Layout considerations for fast switching applications
12.7.1 Low inductive bus bar design
12.7.2 Parasitic turn-on
12.7.3 Gate drive path layout
12.8 Alternative top side chip contact technologies
12.8.1 PCB embedding
12.8.2 Metal clips and metalized transfer mold
12.9 Examples
12.9.1 IMS/PCB embedded GaN power module
12.9.2 Full PCB SiC power module
12.10 Summary
Note to the reader
References
13 Modern insulated gate bipolar transistor (IGBT) gate driving methods for robustness and reliability
13.1 Introduction
13.2 Operation principle of IGBTs
13.3 Basic IGBT gate driving methods
13.3.1 Voltage-source gate drivers
13.3.2 Current-source gate drivers
13.3.3 Optimization and protection principles
13.4 Fault detection and protection methods
13.4.1 Voltage and current overshoot
13.4.1.1 Voltage overshoot
13.4.2 Overload and short-circuit event
13.4.3 Gate voltage limitations
13.5 Active gating methods for enhancing switching characteristics
13.5.1 Closed-loop control methodology
13.5.2 Closed-loop control implementations
13.6 Active thermal control methods using IGBT gate driver
13.6.1 Principles for thermal mitigation method
13.6.2 Thermal mitigation methods
13.6.2.1 Gate resistance adjustment (short-term time scale method)
13.6.2.2 Switching frequency adjustment (long-term time scale method)
13.6.3 Junction temperature estimation methods
13.6.3.1 Static TSEPs
13.6.3.2 Dynamic TSEPs
13.7 Summary
Acknowledgments
Note to the reader
References
14 Prospects and outlooks in power electronics technology and market
14.1 Global markets figures
14.2 Impact of EV/HEV sector
14.3 Wide-bandgap semiconductors
14.3.1 Silicon carbide
14.3.2 Gallium nitride
14.4 Power packaging prospects
14.4.1 Power discrete packaging market
14.4.2 Power module packaging market
14.5 Summary
Note to the reader
References
Index
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