Onsemi to Supply Silicon Carbide to Electric Vehicle Drive Developer

Onsemi and Vitesco Technologies have entered into a long-term supply agreement valued at $1.9 billion over the next ten years for onsemi to supply Vitesco with its latest high-voltage, silicon carbide (SiC) solutions. 

EV powertrain. Image used courtesy of Vitesco

 

As part of the agreement, Vitesco will invest $250 million directly into onsemi’s SiC production capacity to help meet additional demand.

Vitesco and onsemi will also collaborate on next-generation EV traction inverter designs based on onsemi’s EliteSiC technology.   

 

Focusing on an Electric Future

Based in Regensburg, Germany, Vitesco Technologies develops electric drive train solutions for next-generation hybrid and battery EVs. As part of the company’s 2030 strategy, Vitesco seeks to be a leader in developing electrification solutions for e-mobility platforms, facilitating the transition from carbon fuels to electric vehicles.  

The company’s e-mobility product portfolio includes electric drive control units, high-voltage power distribution blocks, inverter drives, and various other power distribution solutions for battery electric, hybrid, and fuel cell vehicles.  

In addition to solutions for electric powertrains, Vitesco continues to support ICE powertrain solutions and Engine Control Units (ECUs) to maximize the efficiency of gas-powered vehicles.   

 

High-voltage inverter for passenger EVs. Image used courtesy of Vitesco

 

End-to-End SiC Supply Chain

The $250 million investment from Vitesco will be used by onsemi for new equipment for SiC boule growth, wafer production, and epitaxy to help ensure SiC production capacity can meet the obligations of the agreement.  

In addition to product design, manufacturing, and testing, onsemi has invested significantly in developing an in-house,  end-to-end silicon carbide supply chain that begins with the raw silicon and carbon materials needed to form SiC substrates. 

 

End-to-end silicon carbide supply chain. Image used courtesy of onsemi
 

The first step in manufacturing is to create a boule, or puck, from raw silicon and carbon. The boule is then formed into transparent SiC wafers through manufacturing steps. Epitaxial (epi) layers are then added to the SiC wafer that dictates the final voltage rating (up to 1700 V) of the end devices (MOSFET, diode, etc.).  

Silicon carbide boule or puck. Image used courtesy of onsemi

 

The high-voltage silicon carbide devices are fabricated on the wafers, where they are individually tested and diced into individual die for assembly, final testing, and shipping.  

In addition to discrete MOSFET and diode components, onsemi also offers fully tested power modules that integrate multiple power components pre-configured for EV power inverters, energy storage, and other applications.    

Key to developing a fully integrated supply chain was onsemi’s acquisition of GT Advanced Technologies (GTAT) in 2021. Founded in 1994, GTAT has developed significant capabilities in silicon carbide crystalline formation, an essential process for developing wafer-ready boules.

 

Silicon carbide wafer. Image used courtesy of onsemi

 

EliteSiC Technology

EliteSiC is a family of MOSFETs, diodes, and power modules based on onsemi’s EliteSiC silicon carbide technology. The solutions are designed to deliver the maximum power conversion efficiency at high voltage in electric drive trains, power generation, and energy storage systems.

 

EV traction inverter block diagram. Image used courtesy of onsemi

 

EliteSiC MOSFET and diode solutions are categorized into product families based on characteristics like voltage rating, on resistance, and switching speed. The SiC technology can accommodate application-withstand voltages ranging from 650 V to 1700 V.

In addition to the recent announcement with Vitesco, onsemi has engaged in strategic supply agreements and collaborations with several eOEMs and suppliers over the past year, working with partners to integrate custom and semi-custom EliteSiC solutions into EV powertrains and other applications.  

In an EV, the traction inverter converts DC from the battery bus (400V and higher) to three-phase AC to power the vehicle motor and drivetrain.