Nexperia Enters IGBT Market With Flexible Range of 600 V Devices

In power electronic design, developers have gained momentum to find new alternatives to conventional power MOSFETs. In this pursuit, new materials and technologies such as silicon-carbide (SiC) and gallium-nitride (GaN) FETs have breathed new life into what's possible for a power transistor.

Beyond these new materials, however, an older technology that still has a strong foothold in power electronics is the insulated-gate bipolar transistor (IGBT). This week, Nexperia entered the IGBT market for the first time with the launch of a new range of 600 V devices. In this piece, we’ll look at IGBTs, trench-gate devices, and Nexperia’s new line of products.

 

Nexperia's new 600 V IGBTs. Image courtesy of Nexperia

 

What Are IGBTs?

IGBTs are a type of power electronic device widely used in many power electronics applications. Existing as a hybrid of two transistor types, the BJT and MOSFET, IGBTs combine the high input impedance and high-speed switching of MOSFETs with the low saturation voltage of BJTs to create an even better transistor.

 

A comparison of transistor types. Image (modified) courtesy of Rohm Semiconductor

 

On a circuit design level, an IGBT consists of four alternating layers of P and N-type semiconductor materials. The gate terminal is insulated from the rest of the device by a thin layer of silicon dioxide—hence the "insulated gate" part of the name. A voltage applied to the gate modulates the conductivity of the device, allowing it to control a large amount of power with a small input signal. This makes IGBTs useful for applications that require high power handling and precise control.

IGBTs have found prominence in power electronics for a number of reasons. First, the insulated gate of the device efficiently controls high power levels, which is crucial in many industrial applications such as motor drives, power supplies, and renewable energy systems. Beyond this, their fast switching capabilities make them suitable for applications that require rapid changes in power levels, such as electric vehicles and high-frequency inverters. 

 

Trench Gate Field-stop Construction

In the world of IGBTs, one architecture that offers another level of performance to the devices is the trench gate field-stop (TGFS) architecture.

The TGFS construction involves etching trenches into the device’s silicon and filling them with a gate material, typically polysilicon. The trench-gate structure replaces the planar gate structure found in traditional IGBTs and increases the channel density, which in turn reduces the on-state voltage drop and improves the device's conduction characteristics.

The "field-stop" aspect of TGFS refers to an additional N-layer near the collector. This N-layer causes the electric field in the nearby N-drift layer to fall off abruptly when it reaches the P+ collector.

The combination of trench-gate and field-stop technologies in TGFS IGBTs results in devices that offer superior performance compared to traditional planar IGBTs. They exhibit lower conduction and switching losses that lead to higher overall efficiency while maintaining a high breakdown voltage.

 

Nexperia Makes Its IGBT Debut

This week, Nexperia entered the IGBT market for the first time with the introduction of a range of new IGBT devices.

 

Nexperia’s M3 vs. H3 families. Image courtesy of Nexperia

 

The new devices are 600 V solutions that range between medium-speed (M3) and high-speed (H3) switching capabilities. Notably, the devices in this family are constructed with a carrier-stored, trench-gate, field-stop architecture, allowing for low conduction losses and robust performance. According to Nexperia, the M3 line is characterized by low conduction losses and switching losses for applications that require switching speeds less than 20 kHz. The H3 line, on the other hand, is meant for high-efficiency performance in applications up to 50 kHz.

An example of a new device introduced in the family is the NGW30T60M3DF, a 30 A, 600 V IGBT. Capable of maximum junction temperatures up to 175°C and 5 µs short circuit withstand time, the device is designed for applications like motor drives for industrial appliances.