Infineon Austria announces breakthrough in gallium nitride wafers

Infineon Austria has succeeded in producing 300-millimeter gallium nitride wafers on an integrated pilot line in the existing 300-millimeter silicon production facility at its fab in Villach, Carinthia. According to Infineon Technologies, this is the world's first wafer technology of this kind for power electronics. Gallium nitride (GaN) is (like silicon carbide) a so-called wide-bandgap semiconductor with a wide gap between the valence and conduction bands. This can be used for SiC MOSFETs, for example, which switch high currents with high frequencies and low losses – at reverse voltages of up to 1700 volts.

This makes it possible to reduce the size and weight of devices such as solar inverters, chargers, motor control systems or power supplies for AI systems. Thanks to higher efficiency, greenhouse gas emissions are also reduced. Applied to electric cars, for example, this means lighter batteries, longer ranges and faster charging. Gallium nitride enables even higher switching speeds than silicon carbide (SiC) and should cost the same at Infineon once production is scaled up. The manufacturer can use existing 300-millimeter production facilities for silicon, as gallium nitride and silicon are very similar in their production processes. Infineon is thus positioning itself as a supplier of wafers made from all three materials: silicon, silicon carbide and gallium nitride.

The latter is the result of the acquisition of the Canadian company Gan Systems, which has been developing the technology in Ontario since 2008. Last year, Infineon took over the Canadian semiconductor manufacturer Gan System; the purchase price was 830 million US dollars. This August, Infineon opened a new factory in Kulim, Malaysia. The first phase, in which Infineon is investing two billion euros, is expected to be fully ramped up by the end of 2026 or early 2027. Further expansion beyond this is planned. However, the first products are already scheduled to be delivered this fall. Initially made of silicon carbide, followed by gallium nitride.

Wideband gap semiconductors

In insulators, the electrons are firmly bound to the atoms of the crystal lattice, whereas they can move freely in metallic conductors. Semiconductors lie in between (hence the name): With energy from outside, for example in the form of heat, light or electrical voltage, bound electrons become free electrons. In the process, they jump from a low energy level (valence band) to a higher one (conduction band) and current flows. In the case of silicon, the band gap is relatively small at 1.1 electron volts (eV).

This is advantageous for solar cells because light from the visible spectrum is sufficient to raise charge carriers from the valence band to the conduction band. SiC and GaN, on the other hand, have a band gap three times as high at 3.2 to 3.4 eV. This is an advantage for power electronics because diodes made of this material only break through, i.e. conduct current, at much higher voltages. The maximum current density that the device can withstand without breaking is also higher due to the large band gap.

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