The first international breakthrough! Shenzhen Pinghu Laboratory overcomes the bottleneck of GaN/SiC single-chip integration technology

On August 7th, the official WeChat account of Shenzhen Pinghu Laboratory announced that the laboratory has made breakthrough progress in the field of GaN/SiC integration, and has developed high-quality AlGaN/GaN heterostructure epitaxy on commercial 8-inch 4 ° tilt 4H SiC substrates for the first time internationally.

It is reported that this achievement has broken the technological bottleneck of the integration of large-sized GaN and SiC materials on a single chip, laying the foundation for the development and industrialization of GaN/SiC hybrid devices. It can be applied in bulk to the preparation of large-sized and high-quality GaN epitaxial materials, providing a highly competitive alternative to the existing silicon-based GaN technology route.

The Pinghu Laboratory in Shenzhen summarized the two major breakthroughs of this achievement. On the one hand, the defect density has been significantly reduced, with the defect density in GaN epitaxial materials decreasing by 10-15 times, which is expected to fundamentally solve the reliability problem of GaN devices and pass the 10-year lifespan verification; On the other hand, the heat dissipation performance has been significantly improved, and the high thermal conductivity of SiC substrates will further enhance the power density and integration of GaN devices.

The 8-inch 4 ° tilt angle 4H SiC GaN epitaxial wafer developed by Shenzhen Pinghu Laboratory has good uniformity and flatness. PL testing shows that the Al composition non-uniformity of the AlGaN/GaN heterojunction barrier layer is about 1.2%; The unevenness of thickness is about 2.2%. The flatness test was conducted on the epitaxial wafer #, and the bending degree (Bow) was only+8.3 μ m.

High resolution X-ray diffraction tests were conducted on the epitaxial wafer, and the half widths of the (002)/(102) plane rocking curves of the GaN epitaxial layer on a 4 ° tilted SiC substrate were 290/296 arcsec, respectively. It was estimated that the dislocation density was about 6 × 108cm-2, which is equivalent to the crystal quality of the GaN epitaxial layer on a non tilted SiC substrate; Compared to GaN on conventional Si substrates, the dislocation density of the material is reduced by 10-15 times. Atomic force microscopy testing shows that the surface roughness of the epitaxial layer is RMS=1.6 nm (5 μ m × 5 μ m). Hall tests show that the two-dimensional electron gas mobility of AlGaN/GaN heterostructures is as high as 1870 cm2/V · s. All the above indicators have reached the international leading level, indicating that the epitaxial wafer has excellent material properties.

This significant progress will provide important technical support for the large-scale application of wide bandgap semiconductors in fields such as new energy vehicles, consumer electronics, and artificial intelligence.